CM2112 Final

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Main Feeder Wires:

Main power feeder wires are the wires that connect the service weather head to the building. Should be rated for 25% more than the actual load.

Staggered Intermittent Weld:

Making a line of intermittent fillet welds on each side of a joint in a manner such that the increments on one side are not opposite to those on the other side.

Flux

Material used during welding, brazing, or braze welding to clean the surfaces of joints, prevent atmospheric oxidation, and to reduce impurities.

Insulation

Materials with low thermal conductivity characteristics that are used to slow the transfer of heat.

Metal Flue:

Metal chamber through which hot air, gas, steam, or smoke may pass.

Expanded Metal:

Metal network made by suitably stamping or cutting sheet metal and stretching it to form open diamond-shaped meshes.

Spatter

Metal particles blown away from the welding arc. These particles do not become part of the completed weld.

Electrical conduit

Metal, plastic or fiber pipes designed to protect electrical cables and wires

Weld Transfer:

Method by which metal is transferred from the wire to the molten puddle.

Hammering

Method of finishing to flatten the weld and stretch the metal back in the desired shape

Power Factor Correction:

Normally used on single-phase, constant current power sources to reduce the amount of primary amperage while welding.

N (wire lettering):

Nylon coating, resistant to damage by oil or gas

Metallic coating

One or more layer of metal on a steel base (base material).

Cement paint

Paint supplied in dry powder form, based essentially on Portland cement, to which pigments are sometimes added for decorative purposes. This dry, powdered paint is mixed with water immediately before use.

Inverter

Power source that increases the frequency of the incoming primary power, thus providing for a smaller size machine and improved electrical characteristics for welding, such as faster response time and more control for pulse welding

Shielding Gas

Protective gas used to prevent atmospheric contamination of the weld pool.

Cable pulling

Refers to installing cable into an electrical conduit- something of an art.

Liquidtight Flexible Nonmetallic Conduit (LFNC-B):

Refers to several types of flameresistant non-metallic tubing. Interior surfaces may be smooth or corrugated. There may be integral reinforcement within the conduit wall.

Radiant Barrier

Reflective barriers that inhibit heat transfer by thermal radiation.

Pipe Sections:

Sections of insulating material in cylindrical form suitable for application to pipes.

Block Insulation

Semi-rigid insulation formed into sections, rectangular both in plan and cross section, usually 90-120 cm (3 - 4 ft) long, 15-60 cm wide (0.5 - 2 ft), and 2.5-15 cm (1-6 in) thick.

Board Insulation

Semi-rigid insulation formed into sections, rectangular both in plan and cross section, usually more than 120 cm (4 ft) long, 60-75 cm (2 - 2.5 ft) wide, and up to 10 cm (4 in )thick.

Pulsing:

Sequencing and controlling the amount of current, the frequency and the duration of the welding arc

Embrittlement

Severe loss of ductility of a metal (or alloy)

Metal Cladding/Jacketing:

Sheet metal fitted as a protective finish over insulation.

Loop diagrams ("loop sheets")

Show the interconnections of individual instruments, including all the wire numbers, terminal numbers, cable types, instrument calibration ranges, etc.

Process and instrument diagrams (P&IDs):

Shows the layout of all relevant process vessels, pipes, and machinery, but with instruments superimposed on the diagram showing what gets measured and what gets controlled.

Underground Feeder Cable

Similar to NM cables, but wires are grouped together and embedded in the flexible material. They feature three plain stranded copper wires (one wire for the current, one grounding wire and one neutral wire) that are insulated with cross-linked polyethylene, PVC bedding and a black PVC sheathing.

Twisted Pair:

Similar to paired cables, but the inner insulated wires are twisted or intertwined

Reducers

Special combination coupling that allows connection of raceways of one trade size to larger or smaller ones.

Torque wrenches:

Special wrenches that exist for the purpose of measuring applied torque during the tightening process.

Direct-Buried Cable (DBC)

Specially-designed coaxial or bundled fiber-optic cables, which do not require any added sheathing, insulation or piping before being buried underground. They feature a heavy metal core with many layers of banded metal sheathing, heavy rubber coverings, shock-absorbing gel and waterproof wrapped thread-fortified tape

Kilowatt-Hour (kWh):

Standard unit for measuring electrical energy consumption: kilowatts x hours

Bands

Strapping used to fasten insulation and/or jacketing in place.

Thermal Stresses

Stresses in metal resulting from non-uniform temperature distributions.

Butt Strip:

Strips of similar jacket material applied around pipe insulation butt joints.

Compression lugs

Stud-type input power connections that are generally made of high conduction wrought copper or aluminum.

Binder

Substance contained in insulation material that stabilizes the fibers (sometimes called a thermal setting resin).

W (wire lettering)

Suitable for wet locations

X (wire lettering)

Synthetic polymer that is flame-resistant

. Expansion joints need to be provided in furnace refractories at regular intervals to avoid overstressing the bricks at elevated temperature.

. For very low temperatures, the use of multiple vapor barriers may be justified

. Loosefill material and unbonded mattresses are liable to compact under the influence of vibration and thermal cycling.

. The ability of air to hold water in the vapor phase is reduced as the temperature decreases.

. When a plaster-type finish is applied, an expansion joint shall be provided by cutting at a circumferential joint in a single layer or in the outer layer of a doublelayer system.

1. In any welded structure it is desirable that butt joints should be used wherever possible.

1. Instrumentation is the science of automated measurement and control.

11. Function diagrams are used to document the strategy of a control system.

13. The narrowing of scope with the progression from process flow diagram (PFD) to loop diagram may be visualized as a process of "zooming in" as though one were viewing a process through the lens of a microscope at different powers.

14. A certain level of uncertainty is perfectly acceptable for a process flow diagram (PFD), because its purpose is merely to show the general flow of the process itself, and only a bare minimum of control instrumentation.

15. Instruments bearing a common "loop number" in the instrumentation process indicate they are all part of the same control system.

17. An open circle instrument "bubble" indicates Field-mounted.

19. The direction of action of each instrument is a typical detail one can see on a loop diagram.

2. The first step in instrumentation is measurement.

21. In instrumentation, each and every instrument has an input and an output, and there is always a predictable (and testable) correlation from one to the other, which help when diagnosing where a problem lies within a measurement or control system.

24. Plastic is a common pipe material for many industrial applications, including instrumentation.

25. In the United States of America, most large industrial pipes are joined together by flanges.

28. On instrument diagrams, flanges are denoted by two short parallel lines, both perpendicular to the pipe.

3. In instrumentation, once the quantity of interest is measured, a signal representing the quantity is transmitted to an indicating or computing device where either human or automated action then takes place

34. By far the most common type of tube fitting for instrument impulse lines is the compression-style fitting, which uses a compressible ferrule to perform the task of sealing fluid pressure.

37. Swagelok gauges are referred to in the industry as no-go gap gauges because their inability to fit between the nut and body shoulder of a tube fitting indicates a properly-tightened fitting.

39. Regardless of the brand, compression-style instrument tube fittings are incredibly strong and versatile.

4. Both measurement devices and the final control device connect to some physical system called the "process".

40. Unlike pipe fittings, tube fittings may be disconnected and reconnected with ease.

41. No special procedures are required to "re-make" a disassembled instrument fitting connection: merely tighten the nut "snug" to maintain adequate force holding the ferrule to the fitting body, but not so tight that the ferrule compresses further around the tube than it did during initial assembly

44. A reducing union tube joins together different tube sizes rather than tubes of the same size

45. Bulkhead fittings are designed to fit through holes drilled in panels or enclosures to provide a way for a fluid line to pass through the wall of the panel or enclosure.

46. Tubing elbows are tube connectors with a bend that are useful for making turns in tube runs without having to bend the tubing itself.

47. Tee fittings join three fluid lines together.

48. Union tees join three tube ends.

49. The only difference between a branch tee and a run tee is the orientation of the pipe end with regard to the two tube ends.

5. The final control device in instrumentation can take a form of a control valve.

51. If possible, a goal in tube bending is to eliminate as many connections as possible because connections invite leaks, and leaks are problematic

52. Twisting, soldering, crimping (using compression connectors), and clamping (either by the tension of a spring or under the compression of a screw) are some of the popular techniques for connecting electrical conductors together.

53. An industry-standard structure for attaching terminal blocks and small electrical components to flat metal panels is called a DIN rail.

54. An obvious advantage of using DIN rail to secure electrical components versus individually attaching those components to a subpanel with their own sets of screws is convenience: much less labor is required to mount and unmount a DIN rail-attached component than a component attached with its own set of dedicated screws

55. A traditional and rugged technique for cable routing is conduit

56. Conduit resembles piping used to convey fluids, except that it is much thinnerwalled than fluid pipe and is not rated to withstand internal pressure as pipe is.

58. A busway is also sometimes known as a bus duct.

6. The common home thermostat is an example of a measurement and control system, with the home's internal air temperature being the "process" under control

A bushing is installed on the inside of the box opening and threaded into the conduit end, separating the conductors from the edges of both the opening and the conduit end.

A common method of installing a flange gasket is to first install only half of the bolts (in the holes lower than the centerline of the pipe), drop the gasket between the flanges, insert the remaining bolts, then proceed to tighten all bolts to the proper torque.

A very simple example of a motor control mechanism is a variable frequency drive (VFD), which adjusts motor voltage, changing the rotation speed

Acceptable methods to remove dirt and dust after manual cleaning and before painting include brushing; blowing with clean, dry air; and vacuum cleaning.

Aerogel insulation systems will not break during shipment.

Aerogels are extremely hydrophobic and therefore have outstanding resistance to moisture.

Aerogels are lighter than other insulation materials.

Aerogels pose no chemical threat to the environment.

Air circuit breakers can be used for low-voltage and some medium voltage circuits

Air flow of an outer surface will tend to reduce the surface temperature and increase the rate of heat loss

Airless spray relies on hydraulic pressure rather than air atomization to produce the desired spray.

Airless spray usually is faster, cleaner, more economical, and easier to use than conventional air spray and applies thicker film.

All instruments connect to their respective processes and to each other by means of pipe, tube, and/or wires.

All larger containers should be mixed by mechanical agitators and brought to a uniform consistency.

All materials should be supplied in the manufacturer's original containers, durably and legibly marked according to relevant standards.

Aluminum conduit is one type of metallic conduit.

An installation may require a lot of bends, and bending conduits on location might damage them or reduce the internal diameter

Any and all holes and surface imperfections should be cleaned and filled in an approved manner before painting

Any surfaces to be coated should be rendered dust-free prior to the application of the prime coat

As a general rule, a vapor barrier will be required over the insulation on all plant working at temperatures below the relevant " dew point" of the ambient air.

At T intersections, it is necessary to weld the butt first fully, and then gouge out the ends to renew the seam edge preparation before welding the seam.

At the junction between preformed insulating materials and fixed steel work, the joint area shall be packed with mineral fiber to accommodate differential thermal movement.

Before any stripping work is carried out, it is necessary to determine what type of insulating material is involved

Before vapor barrier is applied, the insulant shall be smooth and regular with all joints tightly butted together so that there are no gaps.

Blast cleaning is a method of surface preparation in which abrasive particles are directed at high velocity against a metal surface.

Blasting operations should never be allowed in the vicinity of painting work, near wet paint, anywhere that blast abrasive, grit or fallout could impinge on a freshly painted surface, or on any uncovered primed surface.

Care needs to be taken to ensure that vapor barrier does not add seriously to the fire hazard of a complete system.

Cold rinsing, final (hot) rinsing, and preparing metal for painting are postpickling treatments for metal.

Conduit bodies are tubular units with openings at each end for admitting conduits, and providing access to the wires.

Containers that have been previously opened should be used first.

Dense refractory brick is required in most furnaces to withstand the high internal temperature.

Difficult or unusual site conditions will influence the selection or application of insulating materials.

Direct-buried cables (DBCs) have high tolerance to temperature changes, moisture and other environmental factors.

Due to the difference in expansion coefficients of metals and insulating materials, it is necessary to make allowance for the differential movements between the hot surface, the insulant, and the finish.

Each application requires a certain wire size for installation, and the right size for a specific application is determined by the code

Electrical metallic tubing (EMT) is light and bends easily

Epoxy and polyester resins give good resistance against mechanical damage, together with protection against the weather and against chemical spillage.

Excessive pressure should not be applied to the brush.

Fabrication should preferably be complete before surface preparation begins.

Fillet welds may be continuous or intermittent depending on the structural effectiveness of the member to be welded.

Fittings for electrical metallic tubing (EMT) are both readily available and inexpensive.

Flame cleaning of high-strength friction grip bolted joints is totally prohibited.

For coaxial cable, the two inner shields share the same geometric axis

For materials to be used at elevated temperatures, it will be necessary to consider the many factors that may result in deterioration under conditions of service.

Fusion welding is achieved by means of a heat source which is intense enough to melt the edges of the material to be joined as it is traversed along the joint.

Gas shielded arc welding processes could be used for the welding of aluminum alloys.

Gas welding, arc welding, and resistance welding all provide heat sources of sufficient intensity to achieve fusion welds.

Hand cleaning is acceptable only for spot cleaning, and power tool cleaning is acceptable where blast cleaning is impractical or not economical.

Heating enables the solvent content of the material to be reduced, allowing a thinner film to be applied.

Heavier coatings are usually used, and because of the lower degree of control given by the airless spray gun and the high paint flow rate, greater resistance to sagging and tearing is required from the paint.

If a cold surface is at a temperature lower than the freezing point, moisture will freeze and tend to rupture and break away the insulation.

If conservation of heat or power is the deciding factor, the cost savings per year is the most important factor, compared to installed cost.

Impact cleaning tools are characterized by chipping and scaling hammers. With these tools, a chisel is struck by an internal piston and strikes the work surface.

Impact cleaning tools, rotary cleaning tools, and rotary impact cleaning tools are the three basic families of power tool cleaning

In electric arc welding, the flux cored wires (FCAW) are often used in mechanized welding allowing higher deposition rates and improved quality of weld

In flame cleaning at a high temperature, oxyacetylene flame is passed over the surface to be cleaned.

In flame cleaning, the effect of the heat is to remove scale and rust, partly by differential expansion and partly by evolution of steam from moisture in the rust.

In making a butt weld with manual arc welding, where the plate thickness exceeds 5 to 6 mm (~1/4"), it is necessary to make more than one welding pass to deposit sufficient weld metal to close the joint.

Insulation can be classified into three groups according to the temperature ranges for which they are used: low-temperature insulation (up to 90° C; 194° F); medium-temperature insulation (90-325° C; 195-620° F); high-temperature insulation (325° C [620° F] and above).

Insulation is recommended for steam, condensate, heating, and hotwater supply mains, in order to conserve heat and avoid high ambient temperatures.

Insulation materials can be classified into organic and inorganic types.

Insulation prevents condensation on cold surfaces and the resulting corrosion.

Intelligent motor control devices use advanced microprocessors for controlling the power of electronic devices employed in an electric motor.

It is easier to obtain watertightness and oiltightness with welded joints.

Liquidtight flexible metallic conduit (LFMC) is also called 'liquidtight' and 'sealtight'.

Loosefill material and unbonded mattresses are liable to compact under the influence of vibration and thermal cycling.

Low bulk density is normally associated with low thermal conductivity in the low and medium temperature ranges.

Low-temperature insulators are used in low-temperature heating and steam equipment, steam lines, flue ducts, etc

Manual cleaning is the method of preparing the surface of metals using hand or powered tools, such as wire brushes, chipping hammers, chisels, scrapers, and vibratory needle guns.

Mechanical lugs are available bolted with two screws or with four screws.

Mechanical lugs are suitable for brass lightning protection and where there may be plenty of vibration.

Methods of surface preparation include degreasing, pickling, manual cleaning, flame cleaning, and blasting.

Mixing in open containers should be done in a well-ventilated area, away from sparks or flames.

Moisture, oil, grease, corrosion products, dirt, and mill scale are typical contaminants that should be removed during surface preparation.

Moisture/oil resistant connectors are designed to protect the electrical connections from damage caused by oil or moisture

Most connectors have two main parts: the housing and terminals for making the connections

Motor control devices are designed to be controlled in a manual, automatic, or remote manner

National Electrical Code is shorted as NEC

Normally, the theoretical heat loss will be based on the manufacturer's declared value of thermal conductivity and, unless otherwise stated, it will refer to conditions of ambient still air at 20° C (68° F).

One great advantage of flexible metallic conduit (FMC) is its ability to absorb vibrations and allow movement, so it is often used to house wiring for pumps, motors and manufacturing equipment.

PVC conduits cannot be used in hazardous locations, as ground conductors or in locations where they are exposed to ambient temperatures over 50°C.

Paint life depends primarily on surface preparation.

Paint must never be allowed to dry in the gun.

Paint systems are generally specified by the dry film thickness (DFT) of coats and the total DFT of primer, intermediate, and top coat, rather than by the number of coats

Pickling is a method of preparing metal surfaces by chemical reaction, electrolysis, or both.

Power tool cleaning provides a better foundation for the priming of paint than hand tool cleaning

Prior to flame cleaning, any heavy layers of rust should be removed by manual cleaning.

Prior to pickling, cleaning of heavy deposits such as oil, grease, and soil should be done.

Raised-face (RF) flanges are designed to seal against a gasket by means of a set of concentric grooves machined on the face of the flange, forming a sealing surface with far greater leakage path length than if the face were smooth, thus discouraging leakage of process fluid under pressure

Requirements for the preparation of surfaces need to be clearly stated

Rigid metal conduit (RMC) usually has the toughest and thickest walls made from coated stainless steel or aluminum, so they offer excellent protection against impacts, punctures and cuts.

Ring-type joints (RTJ) are typically found on high-pressure applications where leakage control is more challenging.

Since aluminum resists corrosion extremely well, aluminum conduits are preferred in locations where they would be exposed to large amounts of water, or corrosive substances.

Since electrical conduits are essentially a safety feature, you should select the material, size and fittings based on the environment of the installation and the type of wiring it will be housing

Standard methods of rust removal include blasting, manual or mechanical rust removal, flame cleaning, and pickling.

Stud welding may be classed as a shielded arc process, the arc being drawn between the stud (electrode) and the plate to which the stud is to be attached.TT

Sulfuric or hydrochloric acid pickling, Phosphoric acid pickling and Footner pickling are three of the six main pickling methods.

Surface cleaning includes removal of contaminants/coats of materials other than metal and removal of coated material related to the metal (scale and rust).

Surface preparation before manual cleaning includes removing visible oil, grease, soluble welding residues, and salts.

Surface preparation is the essential first-stage treatment of a steel substrate before the application of any coating

Technical requirements should take precedence over economic considerations when the insulating material is required to avoid danger to personnel

Testing the cleanliness of the blasted surface can be done by visual or field testing, and by instrument or laboratory testing.

The National Electrical Code and Local Building Codes regulate the manner of installation and the types of wires and cables for various electrical applications

The adjustable speed drive is a unified combination of devices that enable operators to drive as well as adjust the operating speed of a mechanical load.

The brush should not be dipped more than one-third of the bristle length into the paint to avoid overloading the bristles and filling the heel with paint.

The difference between mouldable (moldable) and rammable material is that the latter is a stiffer mix, making it more self-supporting

The effectiveness of vapor barrier is expressed in terms of the rate at which water vapor is transmitted through it under defined conditions.

The electrostatic spray technique uses expensive equipment and has a slower operation than other spray applications

The entire paint contents should be poured into an empty clean drum or can, ensuring that no heavy paste remains in the original container.

The main advantage of molded insulation is the ease of application and replacement when undertaking repairs for damaged lagging.

The main purpose of insulation is to limit the transfer of energy between the inside and outside of a system.

The number of studs holding each flange set together gives some indication of the pressure of the fluid within a pipe.

The original method of spray application was by air atomization.

The paint should be mixed in a manner that will ensure the breakup of all lumps, complete dispersion of pigment, and a uniform composition

The paint surface should be dry before application of overcoating.

The required life of the insulation system shall be considered because this affects the annual cost and hence the economic thickness.

The required thickness of insulation for any specific application depends on the characteristics of insulating material as well as the purpose of the equipment.

The sequence of metal transfer in dip transfer process are: Establish the arc; wire fed into arc until it makes contact with plate; resistance heating of wire in contact with plate; pinch effect, detaching heated portion of wire as droplet of molten metal; Re-establish the arc

The term surface preparation means the methods of treating the surface of substrate prior to application of coating.

There are many types of individual electrical connectors which are categorized by level, function, and type of termination

There are several types of spray equipment: air, airless, hot, and electrostatic spray.

There are two basic types of monolithic lining: castable refractory and plastic refractory.

There are two contacts in a circuit breaker: a fixed contact and a floating contact

Thermal circuit breakers use heat as a measure of current flowing through a circuit and disconnect once a certain temperature is reached, while magnetic circuit breakers rely on electromagnetic energy created by electricity to trip a switch and disconnect the power supply.

Thermal insulation may be applied for protection of personnel from injury through contact with equipment.

Thermocol is mainly used as cold insulation for piping and cold storage construction.

Thinness creates more space in and around pipe racks and equipment.

Three methods of mounting circuit breakers: fixed mounted; removable mounted and drawout mounted.

To prevent drips and water-logging in the conduit runs, install drains at the lowest points of each run that might be affected, or at locations where water might get trapped and accumulate

To reduce distortion and limit the residual stresses in the structure it is important that a correct welding sequence should be utilized throughout the construction.

Triplex wires are usually used in single-phase service drop conductors, between the power pole and weather heads

Unshielded twisted pair cables (UTP) are more affordable than coaxial or optical fiber cables, so UTP cables are often used in telephones, security cameras and data networks

Vacuum circuit breakers are almost exclusively used in medium voltage circuits because of their compact size and high reliability and low maintenance

Visual inspection of welds is routine procedure, and surface defects are soon noticed by an experienced inspector and surveyor.

Visual, radiographic, and ultrasonic examinations are in common use nondestructive testing methods.

When the technical requirements of the application have been met, the total cost (distinct from the initial cost) during the life of the installation is the prime consideration

Wire Lettering: H represents heat resistance and W represents suitable for wet locations.

With higher current automatic welding processes, thicker plates may be welded with a single pass, but at greater thicknesses multi-pass welds become necessary

Field adhesion testing

Test the adhesion of the coatings after application.

NEC

The National Electrical Code, which regulates the manner of installation and the types of wires and cables for various electrical applications

Abrasion Resistance

The ability of a material to withstand abrasion without appreciative erosion

Zero and Span:

The alternative descriptions to LRV and URV for the 0% and 100% points of an instrument's calibrated range. "Zero" refers to the beginning-point of an instrument's range (equivalent to LRV), while "span" refers to the width of its range (URV − LRV).

Ampacity

The amount of electric current that can flow through a wire.

Current

The amount of electricity flowing past a point in a conductor every second.

Galvanizing

The application of a coating of zinc to steel by a variety of methods.

Retrofit

The application of additional insulation over existing insulation, new insulation if old insulation has been removed, or new insulation over existing, previously uninsulated surfaces.

Diffusion coating

The application of metallic coating, the chemical composition of which was modified by diffusing this at the melting temperature into the substrate.

Solvent

The component of either a liquid or solid solution that is present to a greater or major extent; the component that dissolves the solute.

Workpiece Lead:

The conductor cable or electrical conductor between the arc welding machine and the work.

Automatic:

The control of a process with equipment that requires little or no observation of the welding and no manual adjustment of the equipment controls.

Thermal Conductivity

The degree to which a material conducts heat.

Fill Depth:

The depth the weld penetrates the base metal.

Direct Current Electrode Positive (DCEP):

The direction of current flow through a welding circuit when the electrode lead is connected to a positive terminal and the work lead is connected to a negative terminal to a DC welding machine. Also called direct current, reverse polarity (DCRP).

Direct Current Electrode Negative (DCEN)

The direction of current flow through a welding circuit when the electrode lead is connected to the negative terminal and the work lead is connected to the positive terminal of a DC welding machine. Also called direct current, straight polarity (DCSP).

Cork

The elastic, tough outer tissue of the cork oak that is used specially for stoppers and insulation

Weld Metal:

The electrode and base metal that was melted while welding was taking place. This forms the welding bead.

Shielding gas is obtained from:

The electrode outer coating, often called flux. Filler metal is primarily obtained from the electrode core

Butt Joints (insulation):

The end joints of pipe insulation.

External Casing

The external shell of a circuit breaker that encases the other parts.

Primer

The first complete coat of paint of a painting system applied to a surface.

Root Pass:

The first weld bead deposited in a multiple pass weld.

Blistering

The formation of swellings on the surface of an unbroken paint film by moisture, gases or the development of corrosion products between the metal and the paint film.

Cable size

The gauge of individual wires within the cable, such as 14, 12, 10 etc. (the bigger the number, the smaller the size).

Asbestos

The generic name for those silicate minerals that cleave naturally into fibers, the three important forms being chrysotile (white), crocidolite (blue), and amosite.

Flame cleaning

The impingement of an intensely hot flame to the surface of structural steel, resulting in the removal of mill scale and the dehydration of any remaining rust, leaving the surface in a condition suitable for wire brushing, followed by the immediate application of paint.

Primary Power:

The input line voltage and amperage available to the welding machine from the shop's main power line, single-phase or three-phase AC power expressed in watts or kilowatts (KW)

Flange Cover:

The insulation for a pipe flange composed of the specified thickness of insulation material, which may be preformed.

Toe Line:

The junction between the face of a weld and the base metal

Leg Size

The leg length is usually designated as the size of the weld.

Wire Lettering

The letters THHN, THWN, THW and XHHN represent the main insulation types of individual wires.

Polyvinyl Chloride Conduits (PVC)

The lightest in weight compared to other conduit materials, and usually lower in cost than other forms of conduit.

Wattage

The load a wire can take.

Emission

The manner by which substances are discharged through the air.

Concavity:

The maximum distance from the face of a concave fillet weld perpendicular to a line joining the weld toes.

Convexity

The maximum distance from the face of a convex fillet weld perpendicular to a line joining the weld toes

Tensile Strength

The maximum stress a material subjected to a stretching load can withstand without tearing

k-Value (Conductivity):

The measure of heat in BTUs that pass through one square foot of a homogeneous substance, 1-inch thick, in an hour, for each degree F temperature difference. The lower the value, the higher the insulating value

Pitch

The measurement from midpoint to midpoint of intermittent welds (i.e., spacing)

Amperage (amps):

The measurement of the amount of electricity flowing past a given point in a conductor per second (i.e., current).

Finish Method:

The method of surface preparation for welded items that are not to remain in an "as welded" condition.

Binder

The nonvolatile portion of the liquid vehicle of a coating.

Duty Cycle

The number of minutes out of a 10-minute time period an arc welding machine can be operated at maximum rated output.

Welding Sequence

The order in which weld beads are deposited in a weldment.

Intermediate coat (undercoat)

The paint intended to be used between the primer and topcoat in a paint system.

Manufacturer

The person, firm, or corporation that manufactures and provides the coatings under the provisions of relevant standard

Destructive testing:

The physical destruction of the completed weld in order to evaluate its characteristics.

Arc

The physical gap between the end of the electrode and the base metal. The physical gap causes heat due to resistance of current flow and arc rays.

Process

The physical system we are attempting to control or measure. Examples: water filtration system, molten metal casting system, steam boiler, oil refinery unit, power generation unit.

Terminals

The pins in a connector which provide electrical conduction to make the connections secure.

Voltage

The pressure or force that pushes the electrons through a conductor, causing current (amperage) to flow. Sometimes termed electromotive force (EMF), or difference in potential.

Tinning

The process of coating metal with a very thin layer of molten solder or brazing filler metal.

Absorption

The process of drawing fluid or gas into a porous material, such as a sponge soaking up water.

Fillet welding:

The process of joining two pieces of metal together that are perpendicular or at an angle

Insulation Removal:

The process of removing installed insulation.

Corrosion

The process of wearing away gradually, usually by chemical action.

Process flow diagram (PFD):

The proper form of diagram to represent the "big picture" of a process

Noncombustibility:

The property of a material that enables it to withstand high temperatures without ignition.

Compressive Strength:

The property of an insulation material that resists any change in dimensions when acted upon by a compaction force.

Manipulated Variable (MV)

The quantity in a process we adjust or otherwise manipulate in order to influence the process variable (PV). Also used to describe the output signal generated by a controller.

Quenching

The rapid cooling of metals (often steel) from a suitable elevated temperature. This generally is accomplished by immersion in water, oil, polymer solution, or salt, although forced air is sometimes used.

Thermal Conductivity (Lambda Value):

The rate at which heat is transmitted through a material, measured in watts per square meter of surface area for a temperature gradient of one Kelvin per meter thickness, simplified to W/mK.

Root Opening:

The separation between the members to be joined at the root of the joint.

Corrosion protection

The separation of metallic material from an attacking medium by paint or coating.

Delamination

The separation of the layers of material in a laminate.

Contour

The shape of the top of a finished weld.

Arrow Side:

The side of the joint to which the arrow points.

Wire gauge:

The size of the wire

Process Variable (PV)

The specific quantity we are measuring in a process. Examples: pressure, level, temperature, flow, electrical conductivity, pH, position, speed, vibration.

Wire Feed Speed:

The speed and amount of filler metal fed into a weld, expressed in in/min or mm/s.

Permeability

The state or quality of a material that causes it to allow liquids or gases to pass through it. The time rate of water vapor transmission through unit area of a material of unit thickness induced by unit vapor pressure difference between two specific surfaces, under specified temperature and humidity conditions.

Housing

The structure or case used to contain the terminals, ensure stability of the connections, and protect the electrical contacts from short-circuiting and environmental hazards.

Cross-torquing:

The technique of alternating the torque sequence between four quadrants of the flange, ensuring the flanges are evenly compressed together as all bolts are gradually tightened.

Dew Point

The temperature at which a vapor begins to condense out of the air.

Dew point

The temperature at which moisture will condense.

Drying time

The time required for an applied film of coating to reach the desired stage of cure, hardness, or nontackiness.

KVA (Kilovolt-amperes):

The total volts times amps divided by 1,000, demanded by a welding power source from the primary power furnished by the utility company.

Impulse tube or impulse line:

The tube used as the connecting units between an instrument and a process pipe or vessel.

Coaxial Cable

The two inner shields share the same geometric axis. They feature a tubular insulating layer that protects an inner conductor which is further surrounded by a tubular conducting shield, and might also feature an outer sheath for extra insulation.

Setpoint (SP):

The value at which we desire the process variable to be maintained at. In other words, the "target" value for the process variable.

Lower- and Upper-range values (LRV and URV):

The values of process measurement deemed to be 0% and 100% of a transmitter's calibrated range.

Preformed Insulation

Thermal insulating material fabricated in such a manner that at least one surface conforms to the shape of the surface to be covered and which, when handled, will maintain its shape without cracking, breaking, crumbling, or permanent deformation.

Added R-value

Thermal resistance added to a construction element by insulation.

Flame spraying

Thermal spraying in which coating material is fed into an oxyfuel gas flame, where it is melted.

T (wire lettering):

Thermoplastic insulation

Twin-Lead Cable

These are flat two-wire cables that are used for transmission between an antenna and receiver, like TV and radio.

Aluminum Foil:

Thin sheet of rolled aluminum (0.15 mm thick and under).

Lift-Arc

This feature allows TIG arc starting without high frequency. Starts the arc at any amperage without contaminating the weld with tungsten.

Reducing washers

Threaded reducers, similar to hubs, except both the inner and outer surfaces are threaded. Used to connect conduits to enclosure or box openings that have a larger diameter with locknuts on both sides to fasten them in place

Insulate

To cover with a material of low conductivity in order to reduce the passage or leakage of heat, reduce the surface temperature, or reduce the noise emanating from the object.

Clamps

To fasten conduit runs to fixed structures, like beams, hangers or unistrut channels

Cover

To place insulation and/or finish materials on, over, or around a surface so as to insulate, protect, or seal.

Galvanneal

To produce a zinc-iron alloy coating on iron or steel by keeping the coating molten after hot-dip galvanizing until the zinc alloys completely with the base metal.

Convection

Transmission of energy (heat/sound) from one place to another by movement of a fluid such as air or water.

Conduit Bodies

Tubular units with openings at each end for admitting conduits, and providing access to the wires.

Compatible

Two or more paints or varnishes that can be mixed without producing any undesirable effects such as precipitation, coagulation, or gelling are said to be compatible. Different coats of paint that can be associated in a painting system or other coating systems without producing undesirable effects are also compatible

Reduced Voltage Starters

Two or more starters used for starting a motor in reduced voltage conditions.

Electrical Cable

Two or more wires running side by side and bonded, twisted, or braided together to form a single assembly, the ends of which can be connected to two devices, enabling the transfer of electrical signals from one device to the other.

Mechanical lugs

Typically ring-shaped power connections with two screws or with four screws usually made of high-grade electrolyte copper or aluminum.

Infiltration

Uncontrolled leakage of air through cracks

Adjustable-Speed Drives

Unified combination of devices that enable operators to drive as well as adjust the operating speed of a mechanical load.

Hot Start

Used on some stick (SMAW) machines to make it easier to start difficult-to-start electrodes. Used for arc starting only

Straps

Used to mount the conduit to ceilings or walls using a screws or bolts

Intelligent Controllers:

Using advanced microprocessors for controlling the power of electronic devices employed in an electric motor, these controllers monitor the load exerted on a motor and match torque to the recorded load accordingly.

Pretreatment

Usually refers to the chemical treatment of unpainted metal surface before painting.

Seam Welding:

Welding a lengthwise seam in sheet metal either by abutting or overlapping joints.

Constant Voltage (CV), Constant Potential (CP) Welding Machine:

Welding machine that maintains a relatively stable, consistent voltage regardless of the amperage output. It results in a relatively flat volt-amp curve.

Constant Current (CC) Welding Machine:

Welding machine with limited maximum short circuit current. They have a negative volt-amp curve and are often referred to as "droopers."

Semiautomatic Welding

Welding where the equipment controls only the electrode wire feeding. The welding gun movement is controlled by hand.

Gas Welding:

Welding with the heat from an oxy-fuel flame, with or without the addition of filler metal or pressure

Automatic mode

When the controller generates an output signal based on the relationship of process variable (PV) to the setpoint (SP).

Manual mode:

When the controller's decision-making ability is bypassed to let a human operator directly determine the output signal sent to the final control element.

Blushing

Whitening and loss of gloss of a usually organic coating caused by moisture.

Paired Cable

With two individually insulated conductors, this cable is normally used in DC or low-frequency AC applications.

Humidity:

a measure of the amount of water vapor in the air

H (wire lettering)

heat resistance

Metal spraying

spray coat of metal (usually zinc or aluminum) onto a prepared surface.

Goals in thermal science are to minimize capital and operation costs as well as heat loss.

The pressure on the material in the pot and of the air at the gun should be adjusted for optimum spraying effectiveness.

Hertz

the unit of frequency, equal to one cycle per second

Conduction:

transmission of energy (heat/sound) through a material or from one material to another by direct contact. Materials with low rates make good insulation.

Alkaline

(1) Having properties of an alkali. (2) Having a pH greater than 7

Non-Metallic Sheathed Wires:

2-3 conductor wire used for instrumentation.

Elastomeric

: A closed-cell foam insulation containing elastomers that provide the property of high elasticity.

Canvas

: A closely woven fabric of cotton, flax, hemp, or jute characterized by strength and firmness.

Transducer

: A device converting one standardized instrumentation signal into another standardized instrumentation signal, and/or performing some sort of processing on that signal.

Controller

: A device receiving a process variable signal from a primary sensing element or transmitter, comparing that signal to the desired value for that process variable, and calculating an appropriate output signal value to be sent to a final control element.

Transmitter

: A device translating the signal produced by a primary sensing element (PSE) into a standardized instrumentation signal, which may then be conveyed to an indicating device, a controlling device, or both.

Torch

: A device used in the TIG (GTAW) process to control the position of the electrode, to transfer current to the arc, and to direct the flow of the shielding gas.

Holiday

: A discontinuity in a coating (such as porosity, cracks, etc.) that allows areas of base metal to be exposed to any corrosive environment that contacts the coated surface.

Fiberglass

: A fibrous material made by spinning molten glass. Used as an insulator and heat loss retardant.

Perlite

: A glossy volcanic rock that expands when heated. After processing, used as loosefill insulation material or bound into slabs.

Aerogel

: A homogeneous, low-density solid-state material derived from a gel, in which the liquid component of the gel has been replaced with a gas.

Backing

: A material (base metal, weld metal, or granular material) placed at the root of a weld joint for the purpose of supporting molten weld metal.

Blocking

: A material used to retain the insulation in place in open areas

Plug

: A piece designed to seal off the open end of a tube fitting.

Pickle

: A solution, usually acid, used to remove mill scale or other corrosion products from a metal.

Enamel

: A substance composed of a specially processed coal-tar pitch or bitumen, combined with an inert mineral filler.

Plasma spraying

: A thermal spraying process in which the coating material is melted with heat from a plasma torch that generates a nontransferred arc: i.e., molten coating material is propelled against the base metal by hot, ionized gas issuing from the torch.

Tie coat

: An intermediate coat used to bond different types of paint coats; used to improve the adhesion of succeeding coatings.

Circuit breakers:

: Automatically operating safety switches which operate by measuring heat or current flowing through the circuit.

Plasma plating

: Deposition on critical areas of metal coatings resistant to wear and abrasion, by means of a high-velocity, high-temperature ionized inert gas jet.

Hubs

: Fitting used to connect conduits to bus boxes or enclosures that don't have a factory threaded entry

Heat Loss

: Heat that is lost through air leakage, conduction, and radiation. To maintain a steady temperature, heat losses must be offset by a combination of heat gains and heat contributed by a heating system.

Cryogenic Insulation

: Insulation for extremely low-temperature process surfaces from -100°F to -459°F (absolute zero).

Blanket Insulation:

: Insulation of flexible type, formed into sheets or rolls, usually with a vapor barrier on side and with or without a container sheet on the other side.

Ribbon cables

: Often used in computers and peripherals, with various conducting wires that run parallel to each other on a flat plane, leading to a visual resemblance to flat ribbons

Tungsten

: Rare metallic element with extremely high melting point (3410° Celsius). Used in manufacturing TIG electrodes

Air Space

: The area between insulation facing and the interior of exterior wall coverings. Normally a 1-inch air gap

Finish coat (topcoat)

: The final coat in a painting system.

Heat Transmission:

: The quantity of heat flowing through unit area due to all modes of heat transfer induced by the prevailing conditions.

Instrumentation

: The science of automated measurement and control.

Density

: The weight of a material expressed in kg of a cubic meter of a material (kg/m3 ).

Spectacle blind

A blank metal plate comprised of a regular blind plate attached to an equal- diameter ring by a short tab, the outline of which resembles a pair of spectacles.

Unistrut

A brand name of construction strut channel.

Weather Barrier (Weather Coat):

A breather jacket or coating that allows passage of water vapor and protects from atmospheric conditions.

Dichromate treatment

A chromate conversion coating produced on magnesium alloys in a boiling solution of sodium dichromate.

Polyethylene:

A closed-cell, thermoplastic material used for insulation.

Patina

A coating (usually green) that forms on the surface of metals, such as copper and copper alloys, exposed to the atmosphere.

Conversion coating

A coating consisting of a compound of the surface metal, produced by chemical or electrochemical treatments of the metal.

Aluminum paint

A coating consisting of a mixture of metallic aluminum pigment in powder or paste form dispersed in a suitable vehicle.

Cementation coating

A coating developed on a metal surface by a high-temperature diffusion process (as carburization, calorizing, or chromizing).

Coal-tar epoxy coating

A coating in which the binder or vehicle is a combination of coal tar and epoxy resin.

Coal-tar urethane coating

A coating in which the binder or vehicle is a combination of coal tar with a polyurethane resin.

Anticorrosion paint or composition

A coating used for preventing the corrosion of metals which has been specially formulated to prevent the rusting of iron and steel.

Anodic metallic coating

A coating, composed wholly or partially of an anodic metal (in sufficient quantity to set off electrochemical reaction), which is electrically positive to the substrate to which it is applied.

Hybrid laser-arc welding

A combination of laser and arc welding which produces deep penetration welds with good tolerance to poor joint fit-up.

Countersink

A conical hole cut into a manufactured object, or the cutter used to cut such a hole.

Convex Contour

A contour in which the face of the weld curves out.

Flat Contour:

A contour in which the face of the weld is flat.

Flush Contour:

A contour that requires that the weld be laid or finished in such a way that it rests flush against the part or base material itself.

Air Carbon Arc Cutting (CAC-A):

A cutting process by which metals are melted by the heat of an arc using a carbon electrode. Molten metal is forced away from the cut by a blast of forced air.

Primary Sensing Element (PSE):

A device directly sensing the process variable and translating that sensed quantity into an analog representation (electrical voltage, current, resistance; mechanical force, motion, etc.).

Final Control Element (FCE):

A device receiving the signal output by a controller to directly influence the process. Examples: variable-speed electric motor, control valve, electric heater.

Light Amplification by Stimulated Emission of Radiation (Laser):

A device that provides a concentrated coherent light beam.

Tube fitting:

A device used to couple a section of tube to another tube, or to a section of pipe, or to a piece of equipment (such as an instrument).

Weld Defect:

A discontinuity or discontinuities which, by nature or accumulated effect (for example, total crack length), render a part or product unable to meet the minimum applicable acceptance standards or specifications, designating rejectability.

Anodic coating

A film on a metal surface resulting from an electrolytic treatment at the anode.

Flexible Metallic Conduit (FMC):

A flexible raceway of circular cross section for pulling electric cables through.

Phenolic Foam:

A foamed insulation made from resins of phenols condensed with aldehydes.

Pickle / pickling

A form of chemical and electrolytic removal or loosening of mill scale and corrosion products from the surface of a metal in a chemical solution (usually acidic). Electrolytic pickling can be anodic or cathodic, depending on the polarization of metal in the solution.

Jacket

A form of facing applied over insulation. It may be integral with the insulation, or field applied using sheet materials. A covering placed over insulation for various functions.

Thermite Welding:

A fusion process, the required heat being evolved from a mixture of powdered aluminum and iron oxide.

Galvanized rigid conduit (GRC)

A galvanized steel tubing, with a tubing wall that is thick enough to allow it to be threaded.

Plasma

A gas that has been heated to at least partially ionized condition, enabling it to conduct an electric current

Mineral Fiber:

A generic term for all nonmetallic inorganic fibers.

Mineral Wool

A generic term for mineral fibers of a woolly consistency normally made from molten glass, rock, or slag. Insulation composed principally of fibers manufactured from rock, slag, or glass with or without binders.

Thermal spraying

A group of coating or welding processes in which finely divided metallic or nonmetallic materials are deposited in a molten or semimolten condition to form a coating. The coating material may be in the form of powder, ceramic rod, wire, or molten materials.

Motor controls:

A group of devices that govern the performance of an electric motor in a predefined manner (e.g., starting/stopping the motor, regulating rotation speed).

Thermal Spraying:

A group of processes in which finely divided metallic or non-metallic materials are deposited in a molten or semimolten condition to form a coating

Arc Cutting:

A group of thermal cutting processes that severs or removes metal by melting with the heat of an arc between an electrode and the work piece.

Arc Welding:

A group of welding processes which produces coalescence of metals by heating them with an arc, with or without the application of pressure and with or without the use of filler metal.

Pipe

A hollow structure designed to provide an enclosed pathway for fluids to flow.

Butt Joint:

A joint between two members lying in the same plane.

Lap Joint:

A joint between two overlapping members in parallel planes

Miter Joint

A joint made by beveling each of two parts to be joined, usually at a 45° angle, to form a corner, usually a 90° angle

Cellular Glass (Foamed Glass):

A lightweight expanded glass with small cells, preferably nonintercommunicating (i.e., small, individual cells separated from each other), produced by a foaming process

Coating

A liquid, liquefiable, or mastic composition that has been converted to a solid protective, decorative, or functional adherent film after application in a thin layer. A coating is an electrical insulating covering applied to a metal surface as passive protection against external corrosion.

Touch Star

A low-voltage, low-amperage arc starting procedure for TIG (GTAW). The tungsten is touched to the workpiece; when the tungsten is lifted from the workpiece, an arc is established

Closed Cell Foam:

A material comprised predominantly of individual noninterconnecting cellular voids.

Glass Fiber (Glass Wool):

A material consisting of glass fibers used in making various products, including yams, fabrics, insulation, and structural objects or parts. Mineral fiber produced from molten glass, resistant to heat and fire.

Water Vapor Retarder (Barrier):

A material or system that adequately impedes the transmission of water vapor under specified conditions.

Thermal Insulation:

A material or system that has the property of resisting the transfer of heat.

Workpiece Connection:

A means to fasten the work lead (work cable) to the work (metal to be welded on).

pH:

A measure of acidity/alkalinity of aqueous mixtures

KW (Kilowatts):

A measure of power, calculated as volts times amps divided by 1,000.

Permeance

A measure of the transmission of water vapor through a material or combination of materials, measured in perms.

Liquidtight Flexible Metallic Conduit (LFMC)

A metallic flexible conduit covered by a waterproof plastic coating.

Spraying

A method of application in which the coating material is broken up into fine mist that is directed onto the surface to be coated.

Chipping:

A method of removing surface defects with a chisel, so that the defects will not be worked into the finished product.

Insulating Cement:

A mixture of various insulating fibers and binders with water to form a moldable paste insulation for application to fittings, irregular surfaces, or voids.

Pulsed TIG (TIG-P):

A modified TIG process appropriate for welding thinner materials.

Pulsed MIG (MIG-P)

A modified spray transfer process that produces no spatter, because the wire does not touch the weld puddle.

DIN rail

A narrow channel of metal - made of bent sheet steel or extruded aluminum - with edges designed for plastic components to "clip" on.

Coating system

A number of coats separately applied in a predetermined order at suitable intervals to allow for drying or curing.

Duct

A passageway made of sheet metal or other suitable material used for conveying air or other gas.

Cap

A piece designed to seal off the end of an open tube

Panel Insulation:

A prefabricated unit of insulation and lagging.

Synthetic primer

A primer containing solvent and whose base consists of resins and synthetic plasticizers.

Submerged Arc Welding (SAW)

A process by which metals are joined by an arc or arcs between a bare metal electrode or electrodes and the work. Shielding is supplied by a granular, fusible material usually brought to the work from a flux hopper.

Resistance Spot Welding (RSW):

A process in which two pieces of metal are joined by passing current between electrodes positioned on opposite sides of the pieces to be welded. There is no arc with this process.

Airless spraying

A process of atomizing paint by forcing it through an opening at high pressure. This effect is often aided by flashing (vaporization) of the solvents, especially if the paint has been previously heated.

Laser Beam Welding

A process that fuses material with the heat from a concentrated coherent beam impinging upon the members to be joined.

Laser Beam Cutting

A process that severs material with the heat from a concentrated coherent beam impinging upon the work-piece.

Gas Cutting:

A process that uses gases and oxygen to weld and cut metals, respectively.

Flange:

A projecting collar attached to a pipe for the purpose of connecting to another pipe, valve, or fitting

Chemical conversion coating

A protective or decorative coating that is produced deliberately on a metal surface by reaction of the surface with a chosen chemical environment.

Mastic

A relatively thick consistency protective finish capable of application to thermal insulation or other surfaces, usually by spray or trowel, in thick coats, greater than 0.75 mm

A pipe "flange":

A ring of metal, usually welded to the end of a pipe, with holes drilled in it parallel to the pipe centerline to accept several bolts ANSI: American National Standards Institute.

Ground Connection:

A safety connection from a welding machine frame to the earth.

Backing Gas:

A shielding gas used on the underside of a weld bead to protect it from atmospheric contamination.

Electrical Wire:

A single electrical conductor.

Weld Pass:

A single progression of welding or surfacing along a joint or substrate. The result of a pass is a weld bead, layer, or spray deposit.

Friction Welding:

A solid welding process which produces coalescence of material by the heat obtained from a mechanically induced sliding motion between rubbing surfaces. The work parts are held together under pressure

Friction Stir Welding:

A solid-state welding process, which produces coalescence of material by the heat obtained from a mechanically induced rotating motion between tightly butted surfaces. The work parts are held together under pressure.

Busway or bus duct

A special form of wiring often seen in industrial facilities for power distribution.

Stringer Bead

A straightforward bead in which you either "drag" (pull) or push the torch across the joint with minimal side-to-side movement

Adhesive

A substance used to bond materials by surface attachment

MIG Welding

A subtype of GMAW that uses an inert gas or gas mixture for shielding. Typically used on aluminum and other non-ferrous metals.

Laser Cutting:

A technology that is used for industrial manufacturing applications and uses a laser to cut materials.

Thermal Bridge:

A thermally conductive material that penetrates or bypasses an insulation system, such as a metal fastener or stud.

Rigid Metal Conduit (RMC):

A thick-walled threaded tubing, usually made of coated steel, stainless steel or aluminum.

Electrical Nonmetallic Tubing (ENT):

A thin-walled corrugated tubing that is moisture-resistant and flame retardant

Electrical Metallic Tubing (EMT)

A thin-walled metal raceway having a circular cross section; used to pull in or withdraw electric cables or wires after the tubing is installed in place; uses connectors and couplings other than the threaded type.

Water jet cutter:

A tool for cutting a wide variety of materials using a very high-pressure jet of water, or a mixture of water and an abrasive substance.

Acid pickling

A treatment for the removal of rust and mill scale from steel by immersing it in an acid solution containing an inhibitor. Pickling should be followed by thorough washing and drying before painting.

Aluminum Conduits:

A type of rigid conduit generally used in commercial and industrial applications where a higher resistance to corrosion is needed.

Electric Arc Welding

A type of welding that uses a welding power supply to create an electric arc between an electrode and the base material to melt the metals at the welding point.

Weldment

A unit formed by welding together an assembly of pieces.

Cable Tray System

A unit or assembly of units or sections and associated fittings forming a rigid structural system used to securely fasten or support cables and raceways.

Vapor Barrier:

A vapor check with water vapor permeance not exceeding 1 perm, when tested in accordance with BS 2972.

Twinaxial Cable:

A variant of coaxial cables, which features two inner conductors instead of one and is used for very-short-range high-speed signals.

Breather Coating:

A weather barrier coating designed to prevent water (rain, snow, sleet, spillage, wash water, etc.) from entering the insulation system, while still allowing the escape of small quantities of water vapor resulting from heat applied to the moisture entrapped in the insulation.

Backing Weld

A weld bead applied to the root of a single groove joint to assure complete root penetration.

Slot Weld

A weld between two members, one containing an elongated hole through which the other member is exposed; the hole is completely or partially filled with weld metal, thereby joining the two members; one end of the hole may be open.

Open Root:

A weld joint where adjacent pieces to be joined are not touching and a predefined gap or space is specified. Typically used for high strength joints that require complete penetration (i.e. the backside of the joint is welded from the front side).

Tack welds:

A weld made to hold the parts of a weldment in proper alignment until the final welds are made

Butt Weld:

A weld where two pieces of metal are to be joined are in the same plane.

Backing Bar:

A welding aid used to prevent melting through of a joint when performing a complete-joint penetration groove weld.

Electro-Slag Welding

A welding process that is used for welding heavy structure components.

Laser Welding

A welding process that offers low heat input and minimum distortion of welded plates and stiffeners.

Chain Intermittent Weld:

A welding technique where the weld is created by alternatively welding either side of the metal joint, along the entire joint.

High Voltage Circuit Breakers:

According to the IEC, circuit breakers for controlling highpower transmission lines are rated for 72.5 KV and higher.

Overspray (insulation):

Airborne spray loss of polyurethane foam that leads to undesirable depositions of spray foam insulation on nearby surfaces.

Auto-Crater

Allows a TIG (Tungsten Inert Gas) arc to crater-out, allowing time for the addition of filler, without the loss of shielding gas. Eliminates the need for a remote control at arc end.

TIG Welding

Also called gas tungsten arc welding (GTAW), this welding process joins metals by heating them with a tungsten electrode, which does not become part of the completed weld. Filler metal is sometimes used and argon inert gas or inert gas mixtures are used for shielding.

Spot Welding

Also known as "connecting", joining materials by welding at a number of separate points, usually made on materials having some type of overlapping joint design.

Metallic Sheathed Cable:

Also known as armored or BX cables, they are often used to supply mains electricity or for large appliances. They feature more than one conductor, each of which is insulated individually.

Intermittent Weld:

Also known as stitch welding, where individual weld segments are broken up into regularly repeating weld segments rather than a continuous joint.

Grinding

An abrasive machining process that uses a grinding wheel

Sprayed Insulation:

An adherent coating of insulating material.

Plasma-Arc Cutting (PAC):

An arc cutting process using a constricted arc to remove the molten metal with a high-velocity jet of ionized gas from the constricting orifice.

Stick Welding (SMAW or Shielded Metal Arc)

An arc welding process that melts and joins metals by heating them with an arc, between a covered metal electrode and the work.

Flux-Cored Arc Welding (FCAW)

An arc welding process that produces coalescence of metals by means of tubular electrode. Shielding gas may or may not be used.

Plasma Arc Welding (PAW)

An arc welding process that uses a constricted arc between a non-consumable electrode and the weld pool (transferred arc) or between the electrode and the constricting nozzle (non-transferred arc). Shielding is obtained from the ionized gas issuing from the torch.

Gas Metal Arc Welding (GMAW)

An arc welding process where the arc is between a continuous filler metal electrode and the weld pool. Shielding from an externally supplied gas source is required.

Gas Tungsten Arc Welding (GTAW)

An arc welding process where the arc is between a tungsten electrode (non-consumable) and the weld pool. The process is used with an externally supplied shielding gas.

Electro-Gas Welding

An arc welding process, which combines features of gas and shielded welding with those of electro-slag welding.

Expansion Joint (insulation)

An arrangement in an insulation system to minimize the risk of cracking due to thermal movement.

Triplex Wires

An electrical cable composed of two insulated aluminum wires wrapped with a third bare wire which is used as a common neutral.

Alternating Current (AC)

An electrical current that reverses its direction at regular intervals, such as 60 cycles alternating current (AC), or 60 hertz.

Vermiculite

An expanded mineral insulation consisting of a mica-like substance that expands when heated. The resulting granules are generally used as loosefill insulation

Thermal Resistance (R-value):

An index of a material's resistance to heat flow.

Surface preparation

Any method of treating a surface to get it ready for painting

Machining

Any of various processes in which a piece of raw material is cut into a desired final shape and size by a controlled material-removal process.

Paint

Any pigmented liquid, liquefiable, or mastic composition designed for application to a substrate in a thin layer that is converted to an opaque solid film after application. Used for protection, decoration, or identification, or to serve some other function.

Resin

Any polymer that is a basic material for plastics.

Brushing

Application of a coating by means of a brush

Thermal Insulation System:

Applied or installed thermal insulation including any accessories, vapor retarder, and facing required.

Edge Weld:

Are used where the edges of two sheets or plates are adjacent and are in approximately parallel planes at the point of welding.

Bituminous coating

Asphalt or tar compound used to provide a protective finish.

Fixed Automation

Automated electronically controlled welding system for simple, straight or circular welds.

Flexible Automation:

Automated, robotically controlled welding system for complex shapes and applications where welding paths require torch-angle manipulation.

Arc-Drive:

Automatically enhances Stick welding, especially on pipe, by focusing the arc and preventing the electrode from going out.

Adaptive Hot Start

Automatically increases the output amperage at the start of a stick weld, should the start require it. Helps eliminate sticking of the electrode at arc start.

Organic

Being or composed of hydrocarbons or their derivatives, or matter of plant or animal origin.

Blanket Insulation, Metal Mesh

Blanket insulation covered by flexible metal-mesh facings attached on one or both sides.

Water-blasting

Blast-cleaning of metal using high-velocity water with or without the addition of an abrasive.

Electrical enclosures

Boxes or cabinets which are used to contain electrical components like knobs, switches, controls and the like, to protect them from the environments, as well as safeguard property and life.

Impact Resistance

Capability of an insulation material and/ or finish to withstand mechanical or physical abuse.

Condensation:

Changing a substance from a vapor to a liquid state by removing the heat. Shows up on surfaces as a film or drops of water.

Air circuit breaker

Circuit breaker that can be used for low-voltage and some medium-voltage circuits too. Being classified into two types - plain air and air blast.

Thermal circuit breaker

Circuit breaker that uses heat as a measure of current flowing through a circuit and disconnect once it reaches beyond a certain temperature.

Oil-Based Circuit Breaker

Circuit breaker where both the contacts are submerged in insulating mineral oil.

Medium Voltage (MV) Circuit Breakers:

Circuit breakers rated between 1 and 72 KV.

Low Voltage Circuit Breakers

Circuit breakers used when the maximum voltage is about 1000Vac, and include miniature circuit breakers (MCB).

Blast-cleaning

Cleaning and roughening of a surface (particularly steel) by the use of a metallic or nonmetallic abrasive that is propelled against a surface by compressed air, centrifugal force, or water.

Cable Color Code:

Color coding of cable insulation is done to determine active, neutral and earth conductors.

Polyurethane

Commonly abbreviated PU, any polymer consisting of a chain of organic units joined by urethane links.

Organic

Compounds containing carbon

Coupling

Conduit fitting used to securely link together lengths of conduit and attaching sitefabricated bends.

Unions

Conduit fitting with two separate heads and a locking mechanism which can connect two pieces of conduit together, even if they can't be physically turned.

Bends

Conduit fittings commonly called 'factory bends' or 'elbows'.

Nipples

Conduit fittings that do not exceed 24 inches in length, these are threaded on both ends and can be installed quickly and easily. Used for short runs or between nearby enclosures

Locknuts

Conduit fittings threaded on the inside, with teeth on one surface or both, which grip the surface. Installed on both sides of an opening to ensure that both the conduit and bushing are held firmly in place.

Bushings

Conduit fittings used to create a smooth entry point to conduits without any sharp edges, protecting the conductors from damage during wire pulls. Installed on the inside of the box opening and threaded into the conduit end, separating the conductors from the edges of both the opening and the conduit end

Drains

Conduit fittings used to prevent drips and water-logging in the conduit runs, especially in areas where the temperature varies significantly, or the conduit runs from a warm area to a cooler one, and moisture in the air starts condensing

Weather head

Connection point on building that is used to electrically connect the building to the utility.

Electrical connectors:

Connectors used to join electrical circuits (wires and cables) to form a continuous path for electrical current to flow.

Unshielded Twisted Pair Cable:

Consist of two wires that are twisted together

High Frequency

Covers the entire frequency spectrum above 50,000 Hz. Used in TIG welding for arc ignition and stabilization

Direct Current (DC):

Current that flows in one direction and does not reverse its direction of flow.

Anti-Abrasive Coating

Cushioning material applied where insulation contacts pipe, duct, vessel, or adjacent insulation to prevent eroding of either or both.

DFT measurement

DFT measurement instruments consist of magnetic gauges that measure the thickness of a dry film of a nonmagnetic coating applied to a magnetic substrate.

NEMA Standards 250-2003:

Define hazardous location codes based on both the cause and the nature of the hazardous environment.

Erosion

Destruction of metals by the abrasive action of moving fluids accelerated by the presence of solid particles in suspension.

Motor control devices

Devices used to control motors, named for the operations they control

Functional diagrams

Diagrams used to document the strategy of a control system. In these diagrams, emphasis is placed on the algorithms used to control a process, as opposed to piping, wiring, or instrument connections.

Panel Feed Wires

Electric wires used to power the main junction box and the circuit breaker panels. Should be rated for 25% more than the actual load.

Cavity

Empty space between studs/joists in which insulation is placed.

Raceway

Enclosed conduit that forms a physical pathway for electrical wiring

Active Arc Stabilizer

Enhances arc starts and provides a softer arc throughout all ranges, with less puddle turbulence and less spatter.

. Aerogels have the highest thermal conductivity of any material used for cryogenic service.

. In mild steel the weld tends to have a lower yield strength than the plate material.

.The thermal expansion coefficients of plastic pipe are generally much lower than those of metals.

10. It is typical to view the flow of the process as well as the "flow" of information between instruments measuring and controlling the process in a process flow diagram (PFD).

12. When troubleshooting a complex control system, an instrument technician must use only one diagram that shows all details

16. The type of "bubble" used for each instrument tells us something about its material type.

18. To examine details, including cable types, wire numbers, terminal blocks, junction boxes, instrument calibration ranges, failure modes, power sources, and the like, in the instrumentation process, one must turn to a document called a process and instrument diagram (P&ID).

20. An "up" arrow (↑), in instrumentation, represents a reverse-acting instrument: one whose output signal decreases as the input stimulus increases

23. Safety is affected by improper connections between instruments and the process, but not from instrument to instrument

26. A ring of metal, usually welded to the end of a pipe, with holes drilled in it parallel to the pipe centerline to accept several bolts is called a gasket.

27. Gaskets are manufactured from materials harder than the flange material so that when sandwiched between a pair of flanges, the gasket will not get "crushed" between them to seal all potential leak paths.

31. Flanges differ with regard to their color and thermal conductivity.

35. Swagelok-brand provides a special gauge designed such that its thickness will fit between the nut and fitting shoulder if the nut is insufficiently tightened, but will not fit if it is sufficiently tightened.

36. The Swagelok-brand provides a special gauge that has the ability to reveal an overtightened fitting, but not an under-tightened fitting.

38. Over-tightening of a compression fitting is not as bad as undertightening, as the fitting can form a robust seal even when the ferrule and tube have been deformed

42. Tube fittings designed to connect a tube to pipe threads are called unions.

43. Tube fittings designed to connect one tube to another are called connectors

50. A piece designed to seal off the open end of a tube fitting is called a cap, while a piece designed to seal off the end of an open tube is called a plug

57. Plastic conduits are superior to metal conduits with regard to providing electrical grounding or shielding

59. In the interest of safety and longevity, one can simply route electrical power and signal cables randomly between different locations.

7. In order to safely and efficiently produce a continuous flow of steam, in instrumentation involving steam boiler, one must ensure the steam drum is entirely full of water.

8. At the highest level, the instrument technician is interested in the interconnections of individual instruments, including all the wire numbers, terminal numbers, cable types, instrument calibration ranges, etc.

9. The proper form of diagram for the lowest level of instrumentation with fine details is called a process flow diagram.

A Schedule 80 conduit will have a thinner wall than Schedule 40, so it is not permitted for installations where the conduit will be exposed to physical stresses.

A good-quality vapor barrier is guaranteed to exclude water vapor entirely.

A high thermal conductivity is desirable to achieve a maximum resistance to heat transfer.

A reducer is a special kind of combination coupling that allows you to connect raceways of one trade size only to smaller ones.

A thermal insulator is a poor conductor of heat and has a high thermal conductivity.

Aerogels offer poor resistance to flame spread and smoke emission.

Air circuit breakers operate by increasing the arc voltage, which is the maximum voltage required to maintain an arc.

All refractory must be heated quickly from cold owing to the need to minimize the stresses created by differential thermal expansion.

All surfaces can be prepared for the application of protective coatings by only using one single universal method.

An air space is much more effective for thermal insulation purpose than a space of similar dimensions filled with one of the convectional insulating materials.

An increase in the amount of insulation applied will raise the rate of heat loss through the insulation and raise the total cost during the life of the product.

Applying warm paint to cold steel is beneficial to curing

Asbestos or any product containing asbestos materials shall be applied by means of a spray process.

Blast cleaning could be conducted on surfaces that will be wet after blasting and before coating.

Both normal finishing paints and drum paints require rolling during the storage period.

Cable is a single electrical conductor, whereas a wire is a group of cables covered in sheathing.

Clamps are used to mount the conduit to ceilings or walls using screws or bolts

Coatings should be applied to wet or damp surfaces

Common wire sizes are 10, 12 and 14 - a higher number means a larger wire size, and affects the amount of power it can carry.

Dense brick has a relatively low conductivity.

Electrical metallic tubing (EMT) is commonly known as 'Greenfield' or 'flex' conduit.

Electrical nonmetallic tubing (ENT) can only be used outdoors, in areas where they will not be exposed to physical damage, hazardous conditions, temperatures over 50°C and the conductors do not carry over 600 volts.

Electrostatic spraying can frequently be used for on-site work.

For any given heat loss, a material of low thermal conductivity will be thicker than an alternative material of high conductivity.

Having a riveted construction required less skilled labor in compare to a welded construction.

Hot coatings could be applied to cold surfaces and vice versa.

If compressor units for air spray equipment are powered by a gas or diesel engine, they should be located inside the building.

In repair work correct welding sequences are NOT important, and the procedure does NOT follow the general pattern for butts and seams in plate panels.

Inorganic insulations are based on hydrocarbon polymers, which can be expanded to obtain high void structures.

Internal condensation and ice formation will appreciably increase the effectiveness of the thermal insulating material.

It is acceptable for insulation to interfere with the operation of expansion joints.

Liquidtight flexible metallic conduit (LFMC) has an overall non-metallic outer covering that is not waterproof or resistant to cracking from sunlight exposure.

Liquidtight flexible metallic conduit (LFMC) is durable and strong; therefore, they can be exposed to stresses or encased in concrete.

Molded case external casing is generally used for medium voltage circuit breakers.

Most thermal insulating materials have a higher thermal expansion coefficient than metals.

On thinner plates it becomes necessary to bevel the edges of plates which are to be butted together in order to achieve complete penetration of the weld metal.

Only some paints and paint materials used should comply with the specification given in relevant standards.

PVC conduits are available in both Schedule 40 and 80, which are basically ratios of the thickness of the wall to its outer diameter.

Paint can be applied when the temperature is below 4°C.

Paint that does not have a limited pot life or does not deteriorate on standing should not be remixed before using.

Paints should be stored in open containers to keep them fresh.

Paints should preferably be mixed by hand.

Pickling is NOT considered a desirable method of removing rust and mill scale from structural shapes, beams, and plates in workshops when the cost of such removal is felt to be justified.

Pipes of small diameter have relatively high surface temperatures and low rates of heat loss.

Power tool cleaning is suitable for small and large areas.

RMCs are both light and inexpensive.

RMCs are usually called 'thinwalls', since they have a much thinner wall than others.

Ribbon cables are quite flexible and can only handle both high and low voltage applications.

Steel may be blast-cleaned just before fabrication.

The addition of more water than is necessary to obtain a satisfactory brushing consistency is allowed.

The coating applied to a blast-cleaned surface DOES NOT last longer than similar coating applied to a flame-cleaned surface

The manufacturer's declared value of thermal conductivity is only appropriate to the temperature of use.

The most common gas which used to produce a high temperature flame in gas welding is Hydrogen

The newest paint of each kind should be used first.

The number of coats should be the maximum needed to achieve the specified film thickness.

The paint temperature should not be excessively high or low in any conditions.

The provision of air spaces for thermal insulation purposes is recommended.

The thermal conductivity of materials decreases with temperature.

The thermal conductivity of most insulating materials varies only with temperature.

The ultimate cost of insulation should be the only design consideration factor.

Thermal conductivity is always specified at real-time temperature of the insulation material

Thinner layers of insulation increase the surface area emitting heat and also increase the outer surface that will require protection

Tungsten Inert Gas (TIG) welding process usually used for welding the very thick steel plates (more than 10 mm).

Type 7 enclosures and Type 8 enclosures are non-hazardous location enclosure types.

Water resistant connectors can withstand being submerged and also provide protection for the electrical connections against water damage from splashes or occasional dampness.

When fluids are static in pipes or vessels and the ambient temperate is below the freezing point of the contained fluid, there is no way to prevent freezing

When mixing two-component paints, check and remix each component simultaneously and then blend the two components at a very fast speed until the mixture is completely uniform in color.

flexible metallic conduit (FMC) offers protection against impacts and corrosion, and can be used outdoors, buried or embedded

Manual cleaning is the MOST satisfactory method of preparation, especially for steelwork exposed to severe or moderate conditions.

Constant-Speed Wire Feeder

Feeder operates from 24 or 115 VAC supplied by the welding power source.

Voltage-Sensing Wire Feeder:

Feeder operates from arc voltage generated by welding power source.

High-Performance Insulation

Fiberglass insulation with densely packed fibers, resulting in higher R-values for a given thickness.

Ceramic Fiber:

Fibrous material, loose or fabricated into convenient forms, mainly intended for use at appropriate elevated temperatures. The fibers may consist of silica (SiO2) or of an appropriate metal silicate, e.g., aluminosilicate. Alternatively, they may be formed synthetically from appropriate refractory metal oxides, e.g., alumina, zirconia

Self-Setting Cement:

Finishing material, based on Portland cement, that is supplied as a dry powder and, when mixed with water in suitable proportions, will set without the application of heat.

Conduit Fittings:

Fittings used for connecting runs of conduit together, and for connecting conduit ends to boxes, enclosures or electrical devices.

Pulsed-Spray Transfer:

For this variation of spray transfer, the welding machine "pulses" the output between high peak currents and low background currents. The weld pool gets to cool slightly during the background cycle, allowing for welding in all positions on either thin or thick metals.

Anodizing

Forming a conversion coating on a metal surface by anodic oxidation; most frequently applied to aluminum.

Phosphating

Forming an adherent phosphate coating on a metal by immersion in a suitable aqueous phosphate solution.

Arc Control (Dig):

Gives a power source variable additional amperage during low voltage (short arc length) conditions while welding. Helps avoid "sticking" stick electrodes when a short arc length is used.

Volt-Amp Curve:

Graph that shows the output characteristics (voltage and amperage capabilities) of a welding power source.

Heat Transfer:

Heat flow from a hot to a cold body.

Grounding lugs:

Heavy duty lugs that are used for wires on transformers or steel structures.

Lugs

Heavy duty rings made from high grade electrolytic copper and are available in sizes ranging from #8AWG to 4/0AWG in a wide range of mounting holes. They have tin plating that provides resistance against corrosion and the terminals are CSA and UL listed.

HH (wire lettering)

High heat resistance (up to 194°F)

Power Efficiency:

How well an electrical machine uses the incoming electrical power

Waterproof

Impervious to prolonged exposure to water or water entry.

Explosion Proof

In places where the spark or heat from electrical equipment can cause an explosion or start a fire, the components are housed in purpose-built electrical enclosures.

Manual cleaning

Includes hand cleaning and power tool cleaning.

ISA

Instrumentation, Systems, and Automation society.

Plastic Composition:

Insulating material in loose, dry form, prepared for application as a paste or dough by mixing with water, usually on site, and normally setting under the influence of heat applied to the internal surface.

Underground or Buried Insulation:

Insulation applied on piping and equipment located below grade and usually in direct contact with the surrounding soil.

Cellular Insulation:

Insulation composed of small, individual cells separated from each other. The material may be glass or plastic such as polystyrene, polyurethane, polyisocyanurate, or elastomeric

Wood Fiber:

Insulation composed of wood/cellulosic fibers, with or without binders

Calcium Silicate Insulation

Insulation composed principally of hydrous calcium silicate, and which usually contains reinforcing fibers.

Cellular Elastomeric Insulation:

Insulation composed principally of natural or synthetic elastomers, or both, processed to form a flexible, semi-rigid, or rigid foam that has a closed-cell structure.

Pipe Insulation

Insulation in a form suitable for application to cylindrical surfaces.

Loosefill:

Insulation material (usually mineral wool, vermiculite, or cellulose) used for pouring or blowing into the space to be insulated.

Sprayed-On Insulation

Insulation of the fibrous or foam type that is applied to a surface by means of power spray devices.

Reflective Insulation

Insulation that depends on reduction of radiant heat transfer across air spaces by use of one or more surfaces of high reflectance and low emittance.

Unfaced Insulation:

Insulation with no attached vapor barrier.

Cable tray:

It is a technique for cable routing.

Abuse Coverings and Finishes

Jackets, mastics, or films used to protect insulation from mechanical and personnel abuse.

Non-Metallic Sheathed Cable

Known as non-metallic building wire or NM cables. They feature a flexible plastic jacket with two to four wires and a bare wire for grounding.

Standard Testing:

Laboratory test methodology for determining relative properties of materials at specific conditions.

Leakage or coating resistance

Leakage resistance of pipe or resistance of pipe radially to remote earth.

NEMA

National Electrical Manufacturers Association

Mill scale

Mill scale is the term used for the surface oxides produced during hot rolling of steel. It breaks and flakes when the steel is flexed and paint applied over it may fail prematurely.

Slag Wool Insulation

Mineral fiber made primarily from iron ore blast furnace slag that is spun into a fibrous form.

Rock Wool:

Mineral wool produced from naturally occurring igneous rock.

Globular Transfer:

Named for "globs" of weld metal transferring across the arc in a gravity feed. Droplets across the arc are usually larger than the electrode diameter. It does not produce a very smooth weld bead appearance, and some spatter can occur. Usually limited to the flat and horizontal welding positions, and not used on thin metals.

Transfer

Named for a "spray" of tiny molten droplets across the arc, usually smaller than the wire diameter. Uses relatively high voltage and amperage values, and the arc is "on" at all times after the arc is established. Very little if any spatter is produced. Usually used on thicker metals in the flat or horizontal welding positions

Short Circuit Transfer

Named for welding wire touching the base metal many times per second, can be used in all welding positions and on all thicknesses of metal. Some spatter is produced.

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