Installation and Leveling

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Primary Equipment

Is the first unit of machinery set into place. Maybe pumps, conveyors, compressors, refiners, etc. In most cases, it's referred to as the driven unit.

Datum Plane

Is the horizontal plane from which heights, and depths are measured.

Foundation

Is the main support upon which a machine rests.

Order to set in place

Primary equipment is the first unit of machinery set into place, followed by the transmission and finally the drive unit. (In some situations the transmission unit is the primary unit)

Anchor Depth and Bend Requirements

Straight anchor bolts without deformed ends should be set into the founndation to a depth of at least 25 times their ø Bent anchors or only need to be deep enough to ensure that they do not pull out during tightening or when the machine runs. The bent leg of the anchorbolts is usually at least 4 times the bolt ø

Positioning and Setting Anchor Bolts

(As Built) Is done according to the dimensions on the working drawing. Where there are no drawings, their locations are determines from the existing baseplate, soleplate, or base of the machine. -Each bolt is in the correct location -Bolts sitting straight, not an angle. Crooked anchor bolts interfere with positioning, levelling and placement of the baseplate. -Anchor Bolts protrude above the foundation or floor to allow room for: -Thickness of the baseplate -shimming the baseplate to elevation and level -grout -washers -one or two nuts -

Sets

(Such as a driven-unit) that share a common mounting called a baseplate or bedplate. This provides a rigid, level structure which enables the machine units to be maintained in alignment during operation.

Pipe Anchor Bolts

(Tube) allow the bolt to be moved slightly either in the machine base or in the template holding the holts within the concrete form. Use removable packing waste between the anchor bolt and pipe to prevent concrete from getting in the pipe. After levelling and alignment are complete, during grouting, the pipes are filled with grout. This prevents fluids from being trapped in the pipe and rusting the anchor bolts, weakening them.

Prepare the Machine and Mounting Surface:

-Before it is paced, inspect and make needed modifications to the equipment. Prior to transporting. -Review the mounting method to be used. Determine if it is to be mounted to the foundation, directly to the floor, or on an adjustable mounting. -Layout the machine's position in relation to the existing equipment (or blueprint) by establishing centerlines and reference lines. -Prepare the mounting surface. This includes installing anchor bolts for baseplate soleplate installation, levelling and grouting.

Set the Primary Unit

-Check the bearing clearance and remove locking devices on the transmission unit. -Position, level, and set to elevation the primary equipment

Set the Prime Mover

-Check the bearing clearances and remove locking devices on the prime mover. -Rough align the drive unit to the transmission unit or primary unit

Set the Transmission Unit

-Check the bearing clearances and remove locking devices on the transmission unit. -Rough align the transmission unit to the primary unit

Check the Effects of Alignments of Piping and Other Attachments

-Connect all piping chutes and other attachments and check their alignment for stress etc. so that no strain is placed on the machine -Disconnect from the equipment all the piping chutes etc. Adjust the piping etc. for any misalignment between them and the equipment -Precision align to the tolerances specified in the manufacturers' specifications -If attachments cause misalignment from the specified tolerances, the attachments should be adjusted to eliminate these forces; sprockets and sheaves should be in line and parallel to one another

Handling Machinery

-Plan the move from storage to final installation. -Review lifting specs -Protect all machined surfaces from damage -Lift the load so that it is balanced and oriented in the required installation position

Vibration Isolators

-Prevent machine vibrations from being transmitted to adjacent equipment -Prevent the amplification of internal stress which cause misalignment and wear of the machine elements -Various devices of this type are available, from felt pads between the baseplate and the floor, to a plain spring mount, to sophisticated types which incorporate shock-damping capabilities

Lubricate, Power and Test the Equipment

-Remove flushing oil from equipment. Install the lubricant according to the specifications supplied by the engineer or vendor -Complete the installation of the power source for the prime mover )electricity, steam, etc.). Install other electrical and instrumentation interfaces. -Test run the prime mover. This includes such steps as checking the direction of rotation and doing a load test. -Connect all drives to the primary equipment -Lubricate coupling, chains, and other drive components where necessary -Install all equipment guards and platforms (work stations) in accordance with design standards and WCB requirements - Test run the equipment

Care of equipment prior to installation

-Upon arrival iinspectsand report any damages. Check the packing slip. -Check manufacturers recomendations and owner's requirements as to storage, location, recommended lubricants to protect against rust etc -Fill bearing housings, gear reducers and any other oil lubricated parts with oil. A light flushing oil containing a rust inhibitor is used. Examine openings, such as pumps, fans, refiners, and compressors. Remove any foreign matter and seal the openinigs with overs to prevent contamination. -Unless specified otherwise, rotate the shafts of large units of rotating equipment at least once a month. Do this whether the equipment is in storage or on it's permanent mounts.

Mounting on Structural Steel

-Use a base plate -Make the thickness of the base equal to or greater than the thickness of the unit feet -Extend it under the entire unit -Bolt unit and base plate securely to supports

Establishing Reference Lines

1) Keep the number of lines to a minimum 2)Select an area on the front and back of the baseplate, or in the aisle where a single parallel line can be scribed from one end of the machine to the other. Also, establish a line perpendicular to the first reference line so as to establish two important references to the machine 3) Keep the layout as large as practical. The larger the layout the less chance of small acceptable errors being magnified when projecting lines. 4) Keep reference lines out in the open whenever possible. Lines square to the centreline of the machine should also be out in the open. They should not be under any machine supporting members or components. 5) It is important to establish permanent reference points to facilitate all future rebuilds of large complex machines. These points are usually the intersection of working lines and centrelines. One method of preserving these reference points is through the use of brass plugs or holes filled with an epoxy grout mixture. These plugs are scribed and the intersection of the lines prick punched to preserve the reference point.

Procedure for placing grout

1) Set, level, and bring elevation of the machine base or soleplate. Tighten down the anchor bolts to 50% of the normal specified torque. (Fully tightened after the grout reaches full cure) 2) Install grout forms. Do this before the final alignment check, as carpenters who usually build these forms may upset the baseplate by prying and pounding them. 3) Align and level the baseplate. Some machine manufacturers have a pollicy to finally align only those baseplates that can be grouted in the same day. Where cementious based grouts are used, keep the concrete foundation moist during this alignment. It is better to leave any levelling screws in place until after the grout is placed. 4) Fill any sections of the baseplate which have boxed anchor bolts with some pliable type of material such as fibre board. This prevents grouting from filling the space. 5) Grout the baseplate. On large jobs the grout suppliers's on-site representative provides the technichal expertise needed to do the job to specifications. 6) After the grout has attained sufficient strentght (usually 3-7 days) torque the anchor bolts to their final values. 7)Soleplate installations generally have a cored pocket (counter-bored hole) to bury the hold-down nut on the anchor bolts. Cut the anchor bolt where it protrues above the soleplate. Cut it sllightly below the sruface of the soleplate. 8) Fill the cored pocket with either epoxy grout mixture or molten lead. Finish it flush with the surface of the soleplate. 9) Often it is neccessary to fine-finish the foundation and grout with a cappin of mortar.

Rate of Failure

70% of mechanical breakdowns can be traced to misalignment. The misalignment may be due to poor installation procedures or uncontrollable factors such as machine design.

Using a Template

A strong, rigid, wooden template is an ideal jig to assist in locating and setting anchor bolts. The advantages of a well-made template are: -Can support a large number of anchor bolts being set into the foundation at the same time -Bolt location is accurately maintained while cementing or grout sets -Bolts can be secured in the vertical position -A template can be reused where a number of foundations have the same anchor bolt pattern --A template can be used to align the core drill for drilling holes in the floor and foundations for grouting and setting cinch anchors.

Optical Methods

Eliminate the need for wires to mechanically establish reference lines parallel and square to eachother. May various types of precision __________ alignment equipment are available to determine if objects are straight, flat, square and plumb. The main difference s their degree of accuracy and their versatility. For example the theodolite is often used and the jig transit is still found on some sites.

Mounting Methods

Equipment; -Mounted directly to concrete pads or floors -Set on concrete pads or floors using special mounting -Mounted on structural steel supports or steel floors -On soleplates -On baseplates

Grout

Acts as a structural filler. It is the critical connection that links the bed or soleplate to the concrete foundation. Structural grout is subject to compression and vibration loads and transfers them evenly to the foundation. It is the stable support that maintains the precise alignment essential to longterm service. It can also be used to secure anchor bolts in a machine foundation. The use of sand (2 parts), fine aggregates (1 part), Portland cement (1 par) and water should be restricted to non-critical applications, These on-the-job mixtures tend to shrink, are slow to cure, and often fail to fulfil their task. In early mixes, metallic particles were added to cement mixtures. The theory was that oxidation of the metallic particles produced an overall swelling, and thus no shrinkage. However, this swelling is difficult to control, particularly in moist or wet areas. Today's mixtures contain mostly non-metallic, shrinkage-compensating, expansion agents and admixtures. The two main categories are cementitious and polymeric

Torquing Bolts

After the baseplate or soleplate has been positioned, levelled, and grouted, the anchor bolts are tightened to their specific torque.Anchor bolts are normally torqued to approximately 2/3 of their yield strength, or the vendors specifications.

Wedges

An alternate method of adjustment for the elevation of the base. They may be used to simply list the base to enable shims to be inserted. They may also be used as wedge-shaped shims, replacing flat shims. It is recommended that wedges be removed after grouting and the space filled and finished with additional grout.

Welding to Foundation Rebar

Another method of setting anchor bolts.

Lasers

Another optical tool used to lay out and align machines, machine units, and their components. The use of attachments establishes precise 90° beams that replace scribed lines and wires. Also utilized in establishing elevations, and levelling machine units and components.

Datum Points

Are known as points from which any reckoning (measuring) or scale starts. They are necessary to correlate measurements and horizontal positions for different locations.

Main Reference Lines

Are known by many different names depending on the industrial setting. In pulp and paper, they are called working or control lines. In lumber and manufacturing, they are called lumber lines. In machine shops, they are known as datum or axis lines. Temporary reference lines may be established with chalk, soapstone, braided cotton or nylon twine, or piano wire. Permanent lines are scribed into the floor or marked on plugs set in the floor.

Jacking Screws

Are often used to raise machine units so that shims may be inserted or removed (when aligning and levelling units vertically). Vertical jacking screws or bolts are usually located close to anchor-bolts hole locations in the machine base or at each corner of a soleplate. The distance jacking screws project should be kept short to prevent them from bending. It may be necessary to place temporary shim pads under the levelling screw washers. When using them the base or frame is drilled with clearance holes and nuts are fitted on the underside to provide the jacking action. They are NOT recommended for the use on soleplates. Do not let them get covered in fresh grout so that they can be removed once the grout has set. This ensures that the baseplate is supported by the grout and shims. If it is left in and the grout shrinks, the load will rest on the shim pack and on the screws. Vibration can cause them to self-tighten and distort. Can be used to jack the machine horizontally on their support bases. This is done to bring them back into horizontal alignment with other machine units. These are positioned to push the machine at the base point that provides the most rigid support.

Benchmarks

Are points of reasonably permanent character, established by a surveyor to known elevations. They are used as reference points in surveying and leveling machinery to elevation.

Levelling Scerws, Jacking Screws, and Jacking Bolts

Are used in baseplates, soleplates, and the legs of the machine to facilitate their shimming, levelling, and alignment. They replace wedges, jacks, hammers, and pry-bars. They are uncomplicated, safe and fast. When used on concrete floors or foundations they should be fitted with mounting pads or rested on fabricated steel levelling washers to prevent the end from digging into the foundations and stops it from moving the machine out of position (walking) when tightened.

Baseplate and Soleplate Installation on a Foundation.

Baseplates may be set on foundations with or without machinery units. Soleplates are always set without machinery attached. The anchor bolts are set into most foundations before they are set in place. The installation procedure is as follows: 1) Establish centerlines on the baseplate or soleplate by permanently marking them by prick punch marks for length and width. 2) Clean the bottom surface of the baseplate to remove any rust, scale, dirt or other imperfections that may hinder alignment and level. 3) Clean the surface areas that contact the solid shims with a designed to provide a clean dimple free contact surface. 4) Prepare the corresponding shim locations on the foundation also. To do so, set and level metal pads (the same width and length as the shims) in a mixture of stiff, fast drying grout, These pads are set at each shimming location usually on each side of ever anchor bolts. Be sure there is sufficient room for shimming and that the pads don't interfere with the levelling screws. 5) Prepare the anchor bolts by chasing the threads. The lightly coat with light oil or thread lubricant. 6) check the grouting requirements and prepare the foundation as specified. 7) Install

Detecting and Filling Voids in Grout

Can be filled from the outside. To detect and repair them take a small ball peen hammer and lightly tap the base. A change in tone indicates a void. Further tapping can reveal the size and shape of the void. One method to repair voids is as follows: 1) Drill two holes with 7/16 ø 2) Tap one hole for ¼ pipe thread 3) Thread and screw in a ¼ grease fitting 4) Mix a small quantity of suitable epoxy grout and load it into a grease gun 5) Pump it into the void until it comes out of the relief hole 6) Remove burrs and excess grout from the drilled hole

Prime Mover

Converts potential energy input of varying kinds into a mechanical form to drive other machine units. Known as drives or drivers. Ex; electric motors, steam turbines, and combustion engines. Are the last machine unit to be aligned.

Drop-In Anchor

Made from high-grade steel, internally threaded, and fitted with an internal expansion plug. A setting tool sized to fit the anchor is required to set the expansion plug. This plug expands the anchor causing it to grip the sides of the hole.

Chemical Adhesive Anchor

For heavier applications, chemical adhesive anchors are used. The adhesive anchor obtains its holding power from the bond between the anchor stud and the base material. A two-component adhesive (resin and hardener) is mixed with a filler during the setting operations. One manufacturer supplies the epoxy resin, hardener and filler in a glass tube, which is inserted into the drilled hole. The impact of the anchor stud breaks the glass, mixing the epoxy and filler activating the chemical reaction. (thermal setting)

Controlling Vibration

Gang saws, large reciprocating compressors, crushers and other equipment can transfer vibration and noise, this must be eliminated. This problem is more acute today because of the increased capacity and speed of modern equipment and because of environmental and safety concerns. A basic way to minimize and prevent vibration transfer is to use large, well-designed foundations. They may also be isolated from the surrounding floor by means of dead air spaces or vibrations insulators such as felt, cork, insulation or any resilient material.

Fixed Anchor Bolts

Heavy duty, fixed anchors are set by permanently grouting them in place or embedding them into concrete foundations when it is placed. Their design depends on; -Type of machine -Foundation design -Thickness and quality of concrete -Types of loads to be applied to the anchor and machine The end may be modified before installation. The burried end may be deformed by bending it into an L-shape or it may be bolted or welded into a plate washer or a length of angle iron. This ensures that it is firmly held in a fixed position in the concrete and allows the concrete more surface area to grip.

Establishing Elevation

If the baseplate is isolated, establish elevation from the datum plan with an optical tool. The initial datum plane elevation was established from the surveyor's benchmark. Use a precision machinist's spirit level and straightedge to establish elevation from a previously aligned adjacent baseplate. If no leveling points are provided then select a clean flat surface on the machine such as a main shaft to mount the level.

Straight Line diode Laser Transmitter and Detector

In most systems, the laser beam is visible and the effective measuring range of up to 15 m. Resolution in ideal conditions can be accurate to 0.01 mm (0.0004") or higher. The transmitter produced a visible laser beam providing an accurate line of reference. A position-sensitive detector determines the centre of the laser beam making it possible to measure the displacement to reference points on a machine unit, baseplate, or other components. By moving the detector to different measuring points on the object, new sets of accurate measurement values can be obtained. These values are interpreted in the same way as the calibrated graduations on a precision spirit level. They determine the amount of adjustment required to bring the reference points into alignment. Detectors can be mounted on various types of bases. Magnetic base are used to attach detectors to vertical and overhead ferrous metal surfaces.

Dowel

Is a straight or tapered pin preferably with jacking (removal) nuts. They are used to ensure permanent location and alignment of the machine to it's base. Two dowels are usually used in each unit and they are located at diagonally opposite corners.

Machine

Is any device to which power is supplied at one point and does work at another. Most rotate, though may incorporate additional subsidiary mechanisms such as linkages, slides, gears and reciprocating components.

Theodolites

Is simple and versatile and is more accurate thatn the jig transit(it is capable of measuring to one second of an arc) It can establish a plane at any required angle to the datum line of sight in both the horizontal and vertical plane. In addition, it can be used to position, level and align machine units and components. Scales or targets attached to reference points on the soleplate, baseplate, or the machine itself, establish reference points for this purpose. Before using one it must be set up correctly, this involves: -Levelling instrument -Aligning the instrument to reference points or datum line of sight -Checking for instrument error To improve accuracy and efficiency do the following; -Allow time for it to stabilize at an ambient temperature particularly in unheated buildings -Avoid obstructions to the line of sight. These may be due to heat waves, glass, reflecting surfaces, and shooting through restricted locations. -Where possible locate all optical equipment where it is a minimal risk of being knocked over.

Establishing a Reference Line

Is the first step in any installation alignment procedure. This is done either employing mechanical or optical methods. Every machine layout presents different problems, in some situations engineering, have an established procedure to follow. Location of most working lines are dimensioned on the foundation's drawings. Where no procedure is dictated, the millwright must evaluate the situation to determine the most appropriate line locations and methods to establish them. Keeping in mind the cost, accuracy required, the speed of the equipment, availability of tools, and they type of machine operation. 1) Establish the machine centreline 2) Establish a working offset and parallel to the centreline. This line should be in an unobstructed location. In this location, the line will no interfere with the installation of soleplates, baseplates or the machine. Use these lines to locate and position -The template for locating anchor bolts -Anchor-bolt hole position for securing machinery directly to floors. Extra working lines are needed to help -Locate the machine on baseplate or soleplate. -Hold-down bolt hole locations in the baseplate and soleplate -Various attachments and components

Piano Wire

Is wire with very high tensile strength. It may be drawn extremely taught, giving a straight true line that does not stretch, loosen or snag. It is used as a reference or control lines in three dimensions for machinery layout and installation.

Other uses for Straight Line diode Laser Transmitter and Detector

Lasers are not restricted to levelling applications. Due to the straight line nature of the beam, they are often used to replace the straight edge and piano wire. They may be used to check flatness of soleplates, and the straightness of shafts, beams, machines and other mechanical components. Other attachments (such as the pentaprism) enable the beam to be directed at a 90° thus establishing working lines without the use of a wire.

Soleplates

Machines that don't come in sets should not be mounted directly to a foundation. They first must be fastened to heavy metal plates called _________________ or sub-bedplates that are anchored into the foundation.

Stud-Type Expansion Anchor

Made from high-grade and are assembled with a split ring wedge. (Kwik-Bolt)

Designing and Fitting Guards

Millwrights must often design and fit guards. They must take care that: -There are proper clearances for moving parts -Adjustments, inspections. lubrication can be done safely -There is little danger of operators tripping over the guard or over projecting parts -All the guards, covers, or enclosures are strong enough to not give way -There are appropriate guards at: -The point of operation (zone where the work of the machine is performed) -Starting devices (both hands of the operator out of the danger zones) -Feeding devices (pinch points) -Any electrical interlocks needed are in place. These are used to ensure guards are in the proper position for the operation of the machinery -Any electronic controls used as guarding devices are in place. They are interrupted energy sources to start and stop the machine to protect danger zones

Foundations

Most machinery installation procedures start at the machine foundations substructure since the settlement of the foundation introduces misalignment in the equipment. It is essential that the foundations of installed machinery be solid and rigid. The footings must be firm and large enough;ugh to carry the distributed weight safely. concrete foundations for large heavy machinery should rest on a firm grounding such as rock, hard clay, well-compacted sand or gravel. If the ground is less firm the weight should be distributed over a larger area. If the soil is wet or soft, Pilings may be needed, or vertical supports.

Equipment Guards

Must be installed before test running any equipment. They should be put in place after the machine units have been aligned, couplings installed, lubrication checked. and any other pre-start criteria have been meet. Guards are manufactured to design standards that comply with WCB and local building code regulations. These regulations state that exposed moving components shall be completely enclosed to prevent contact by workers.

Grout Selection

No single grout will suffice for the many different applications and conditions found in the field. When selecting you must ask -Will it be exposed to chemical atatck? -Will it be put into service in less than 16h -Will the temperature at the time of placing be less than 5°C -Will it be exposed to high vibration -Will it be required to produce a high bond to steel -What will the service temperature be If the answer is yes to any of these first 5 points, it is likely that the polymeric group of structural grouts is required.

Test Runs

Obtain any special instructions for the safe start-up of equipment from supervisors or engineers. Obtain a release from the engineers, operators. or other appropriate persons. This release should preferably be in writing. Before test-running the machine, do the following: -Complete all checklists -Ensure all incoming lines and pipes are flushed and all vessels are drained and cleaned -Make sure that pump suction have start-up screens -Rotate all moving parts by hand to ensure that they move freely -Re-check all lubrication in the immediate area and check for any physical obstructions Test run the equipment (usually in the presence of the engineer). Run it for the length of time needed to check-out the complete operating system. During the test run check all components for any noticeable problems (temperature rise or vibration). After shut-down, re-check and correct any misalignment, lubricant levels etc. If the equipment is not immediately put into service, keep it in good condition according to the manufacturer's specifications and company policy. Periodically inspect it for proper lubrication and rotate the equipment or run it (for example every 2 weeks).

Methods for Existing Floors

One of three methods is used when the floor foundation already exists --Layout the position of the bolt holes working from dimensions on the drawing -- a) Position the equipment and mark the location of the anchor bolts on the floor b) Core oversized holes into the floor at the approximate bolts locations c) Grout the anchor bolts to secure them --a) Drill the holes as specified for the cinch anchors b) Set the anchors as specified for the cinch anchors

Plant Datums and Machinery Datums

One surface is chosen to maintain the reference point or a reference plane. For example on a paper machine, the underside of the pedestal may be chosen as the elevation 0.000". All heights of components are shown on the machine drawings as relative to this level surface. Ideally these datums are correlated so that everyone uses the same point for the project. Features of individual components of the machine may also be used as datums. The positions of these features are relative to the main datum feature. Features may include most centres of (and machined surfaces on) shafts, housings, mountings surfaces,or other components. These are often used to horizontally position the machine.

Brass Plugs

Provide a surface on which to mark and preserve reference points where reference lines intersect on the baseplate or floor. In the floor they are subject to much general abuse and therefore are less permanent than the ones in the baseplate. One at each intersection of each working line is sufficient. Baseplate and soleplates offer the most permanent location. To install; 1) Drill and tap 13 mm brass cap screw 2) Cut the cap screw off at the baseplate and file it flush 3) Scribe the main working lines onto the exposed plug surface. 4) Drill the intersection no larger than 1 mm to preserve the point for future reference. On the floor they should be approximately 50 mm and set 75 mm deep. They should have machined grooves in the sides which allow them to be set in position with grout or glued with an epoxy grout.

Levelling the baseplate using a tilting level

Several machine levelling operations may be carried out to advantage with the aid of optical equipment. This is a precision level equipment with an optical micrometre. This provides a horizontal line of reference from which displacements can be read in thousandths of an inch and hundredths of a millimetre. Set up a time for this equipment is considerably less than for the adjustment of a theodolite. Since levelling deals with lines of sight perpendicular to the forces of gravity, a simple instrument levelling procedure becomes the sole operational requirement. Hence fixing of equipment over wire reference lines or brass plugs is not necessary. These levels may be conveniently situated in any location offering an unobstructed view of the points to be levelled.

Boxed Anchor Bolts

Some hold-down bolts are subject to severe vibration and are liable to break at the thread section. In these cases, they are often installed through a sleeve that extends to a pocket in the foundation. The pipe acts as a sleeve around the bolt, and the box provides clearance so that the bolt can be replaced. These are mainly used on large mill machinery.

Independent Machines

Stand-alone without the need to be aligned. Sufficiently rigid and strong that they may be mounted directly to the floor or foundation.

Polymeric Grout Filler

Synthetic grouts. They include epoxy resins, polyurethanes, and others. These are supplied in units containing separate packages of resin, hardners and specially graded aggregate. These grouts are non-shrinking, and have excellent adhesion qualities with most materials. These need to be mixed with an appropriate mechanical mixer in a chemically resistant container. They should be mixed until a complete uniform blend is attained (5-7 m) Advantages include: -Moisture insensitive -Resistant to corrosion, impact, vibration, and chemicals. Disadvantages: -Limited shelf life (1 year) -Short pot lives (30 m to 1 h)

Minus Elevation

The foundation is constructed below the desired level by 19 mm to 38 mm (¾" to 1½") -Eliminates concern about foundation shrinkage -Provides space for shimming to elevation. -Provides space for grouting the baseplate or soulpate -38 mm is a practical thickness for shimming and grouting

Levelling

The procedure ensures that the mounting points for the individual machine units are, true (no distortions), at the correct elevation, and level. The recommended practice is to raise the low points to match the highest points (datum) by shimming. Caution: before starting to do this, check that every shimmed location makes full contact with the machine foundation and the baseplate or soleplate. Failure to do this distorts the plate making precision alignment, levelling, and the subsequent coupling alignment difficult and inaccurate. Plates are brought to elevation when they are levelled: -Primary unit soleplates are accurately brought to their required elevations. -Soleplates of machine transmission and drive units are brought to a minus elevation of 3 mm - 5 mm (or as specified). This allows for later precision alignment to the primary unit Shim packs are placed between the baseplate or soleplate and the metal pads grouted to the foundation. Levelling or jacking screws, taper wedge shims, or pry bars may be used to assist in this task. To correctly position the baseplate, a piano wire, normally located parallel to the machine centreline is used as a locating reference for the baseplate centreline.

Building Tie-In

The relationship of the equipment to the structure of the building. Mainly dictated by the required position of a major piece of equipment. Other factors such as the movement of materials and location of power sources.

Concrete

These foundations may be constructed of solid or reinforced concrete. Form and concrete foundation work is most often done by other trades. Millwrights usually start their installation work at existing anchor bolts embedded in Concrete. In some cases, millwrights are required to fabricate, position and install anchor bolts. After the concrete is cured the position of the anchor bolts should be checked against the location of the anchor bolt holes in the machine (as built). Should errors be found they must be recorded and the necessary modifications made to the baseplate (or soleplate) and/or foundation anchor bolts.

Cementious Grout Mixtures

These grouts are Portland cemen-based materials blended with special agents. They require only the addition of water to produce the consitency required for each particular job. Most have service temperatures of above 176° These products are designed to be used as either a dry pack, plastic, or fluid consistencies. Do not use salt water. Advantages include: -No special tools required for mixing -Simple to use -Just add water -Cleans up with water

Precision Rotating Laser

These units employ a detector to determine the position of the beam to establish the elevation. These are accurate to 0.01 mm (0.0004") over a distance of 10 m (32.8')

Construction Rotating Laser

This produces a safe, visible laser beam. This beam creates a 360° reference plane from which elevations can be established. Accurate to 4.7 mm (3/16") at 70 m (200') This tool is satisfactory for rough millwright work.

Adjustable Machinery Mounts

To provide mobility required in manufacturing plants, machinery is mounted on machinery mounts or machine levellers. In these cases the machinery units are freestanding and it may be subject to frequent changes-over or change of position mount. The levelling features incorporate double wedges that enable a machine to be levelled to precise limits in a minimum amount of time. -Ensure that it is clean and greased so that it does not jam. -Always use mountings that are designed to carry the load of the machine

Transmission Units

Transmit mechanical energy from a prime-mover to a driven machine. This usually increases the torque and reduces the speed. Ex; gearboxes, differentials, and variable speed drives. For alignment purposes, the unit may be referred to as either a driven unit or a drive unit. A _________________________ such as the common drive on a multi-vacuum pump assembly is usually regarded as the primary unit and is installed first.

Mechanical Methods

Two methods of establishing reference lines square to each other are the swing arc method and the 3-4-5 method. Most often piano wire approximately 0.75 mm is used to represent the centreline. The longer the wire the less apparent the errors in establishing short lines square to it. Anchoring devices at each end of the wire help to secure and stretch the wire. These need to be adjustable to position the wire and set it horizontal. Obtaining an accurate square line depends upon the accurate transfer point from the wire. The level, plumb-bob or scale and square head may be used to do this. Take the following precautions as you work: -Do not push the wire -Keep the scale and square head perpendicular by employing an adjustable base -Where possible trammels and pin gauges are employed for the swing arc method and establishing parallel lines. -Always double check all measurements and line positions. -When plumb-bobs are employed to transfer lines by draping the line over the piano wire or existing machine components, keep the length of the line to a minimum. -In situations where the plumb-bob is used as a reference point it is advisable to use heavy plub-bobs and/or submerge the plumb-bob almost completely in a can of oil.

Shims

Use few a possible with a max of 4 Flat metal plates that provide a firm adjustable support at points where the weight will be concentrated. Should be the adequate size in sufficient locations to provide rigid support to the baseplate or soleplate. Must bear equal weight at all locations. This prevents distortion of the baseplate or soleplate. Ones produced at the site should be, shaped to fit around and as close to the anchor bolt as possible. Make sure they are free and clear of burrs. The material should preferably corrosion resistant. Solid options should be used where possible. Thinner than 1/8 should not be built up to more than 3/8 in thickness. Use the minimum number of thin ones. Pre-cut ones are mostly confined to the precision alignment of the individual machine. However when used, their initial cost is greater, but they require no time to produce and have fewer inaccuracies due to burrs, or kinks.

Levelling Screws

Used in machines that are set directly to the floor and not grouted in place. The machine is fitted with threaded holes at the anchor bolt or supporting locations to accommodate them. A locknut secures them once the correct level is set. They are designed to support the weight of the machine. When the machine is bolted down with anchor bolts, take extra precautions to ensure that each screw supports its share of the load. Tightening the anchor bolts may stress or twist the machine base. They also allow the level to be maintained from time to time.

Benchmarks and Datums

Used to establish a machine's elevation and horizontal position. The elevation point or ________________ is the vertical distance of the point above a particular surface level. This level surface is called a _________. The height of the surface above the ground is arbitrary. Usually, a series of _________________ is established within the plant by the surveyor. Machinery is positioned to elevation from them.

Centrelines

Used to establish the exact position of machinery. They are established on the machine base or baseplate for both the length and the width of the machine base. Take care to avoid inaccuracies due to the thickness of the etched lines or the wire used. If they are first established as chalked lines, make them permanent by some means such as prick punching. Constructed using mechanical or optical methods employing one or a combination of: -Reference points =Benchmarks -Datums -Centerlines of existing machines

Anchor Bolts

Used to firmly secure the machine baseplate or soleplate to a concrete foundation. Also used to fasten machines directly to concrete floors. Most large installations require anchor bolts that are custom made to suit the anchoring requirements. Anchors that are commercially available are smaller and are often referred to as chinch anchors. Hold-down bolts and hold-down screws are often referred to as anchor bolts. Their primary purpose is to secure machine units to the baseplate, soleplate, or structural steel foundation.

Preventing and Filling Voids

Voids cause by grout not completely filling the area beneath the baseplate to guard against areas of stress concentration. Voids can lead to: -Cracked foundations -The soleplate pulling and twisting under load -An internal soft food that cannot be detected on the machine in place The machine can be damaged because the foundation cannot support the load, particularly the extra load during start-up or shock loading. Full contact between the baseplate grout and concrete foundation is best assured by mixing the grout to a plastic or fluid consistency. The placing technique is tailored to the specific installation. It depends on the dimensions of the plate and the access space to place the grout. Rods, chains or strapping can help move the grout under the base. A small hole may be drilled into the baseplate in areas where air may be trapped preventing a void or an air pocket.

Mechanical Expansion Anchor

Where anchor bolts need to be installed into existing concrete, these may be used. There are many different styles, they are classified as heavy duty, medium duty, or light duty.

Reports

Where possible, Installation records should be maintained for each piece of equipment. It is recommended that equipment tags be used. Many contractors require the tag to be attached to the equipment before installation. As each stage of the installation is completed, that section of the tag is filled in. In addition, it may be necessary for the millwright to report directly to the supervisor at the completion of each step. May also be required to file equipment reports to be checked by the engineer.

Dowelling

Where required, primary, transmission, and prime mover units should be dowelled to the machine base to ensure permanent alignment. Tapered dowels (pins) are usually used for this purpouse as they facilitate fast removal for the maintenance of equipment. If equipment is dowelled after realignment, the holes may need to be re-reamed. The pins used to have a standard taper of ¼ per foot. Reamers come in standard sizes for these pins and range from a No. 6/0 to No. 10 Recommended dowel diameters are: -For couplin-connected equipment, approximately half the driameter of the hold-down bolt. -For indirect-drive equipment the dowel diameter should be the same size as the hold-down bolts.

Self-Levelling

Where the floor is not flat, smooth, or level, self-levelling machine mounts are used. These incorporate a rocker in the design to compensate for the misalignment.

Placing Grout

You must prepare the machine foundation before setting the machine or machine bases. To do this: -Clean off all dirt, oil, grease, and loose materials -Roughen the surface with a needle scaler or brush hammer for better adhesion -Under extreme weather conditions (temps less than 5°C) the grouted area must be protected and heated unless you are using urethane grout which can be placed as low as -10°C -When using cementitious grouts, saturate the concrete surface to be grouted with water. Remove any freestanding water before placing the grout.

Levelling the Baseplate Using a Precision Level

obtain ratio and multiply by feeler gauge thickness xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx 1) Determine the ratio of the length of the precision level to the measured distance between the datum and shimming point. Always work from the baseplate high point (datum) 2) Use the level to determine the amount of adjustment required to bring the level into a true horizontal position. Feeler gauges may be used to determine this measurement by inserting sufficient feeler blades under the low end of the level. 3) The thickness of the adjustment shims required is the ratio times the feeler gauges measurements: A=Tx(L1/L2) T= thickness of the feeler blades (or graduation reading from the level) L2= The distance from the highest shim location (datum) to the low shim location L1= Length of the level A= Shim adjustment requirement 4) Repeat this calculation for the width of the baseplate. Always for from the highest point and to each shim point. 5) Shims all the shim points with the calculated thickness of shims. 6) Re-check the level of the baseplate. Always tighten the anchor bolt nuts to 50% of their torque values before taking readings with the level 7) Once level, check the elevation and determine the necessary shim adjustment. 8) To make elevation adjustments, just add or remove equal amounts of shims from all shim points. The precise adjustment can be difficult when wedge shims are used, and a dial indicator should be used to ensure that each shim location is adjusted the correct amount.


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