chapter 29 shielded metal arc welding

why must materials be beveled when welding thicker materials?

beveling increaes the surface are of the bond and helps ensure penetration through the base metal

what is the process of surface preparation before welding ?

cleaning and fitting pieces to be welded, this includes, cleaning them from contaminants and oxides

a ________ machine is a type of machine that provides an even supply of ampere to the electrode

constant current

a ___________ is a raging that indicates how long a welding machine can be used at a given output current without damaging it

duty cycle

the work piece connector can also be correctly referred to as the ground

false

electrode with a heavy iron powder flux

fast fill electrode

an electrode providing deep penetration and only moderate amounts of fill

fast freeze electrode

what metals work best in the arc welding process

ferrous metals= mild steel, carbon steel, and cast iron

an electrode that produces a medium arc and has a moderate deposition rate

fill- freeze electrode

requires welding to be performed in combination of different positions

fixed pipe welding position

the easiest position for the beginning welder to master

flat welding position

the electrode leads carries current from the machine to the electrode _____________ an insulated clamp that holds the welding electrode

holder

a welding position in which the weld axis is horizontal and the two parts aligned apppin the same vertical plane

horizontal welding position

___________ are foreign materials , such as slag, tapped within the finished weld

inclusions

an electrode that produces a medium penetrating arc and a smooth moderately high deposition rate

low hydrogen electrode

in this position the electrode is pointing up at a downward facing joint

overhead welding position

the direction of flow of an electric current

polarity

waste that forma on top of the head is called

slag

sheilded metal arc welding is also known as

stick welding

what is the purpose of the flux on the welding rod ?

the flux chemically reacts to heat of the arc using the oxygen around the molten weld to form an oxygen free shield around the weld pool

on a 4 digit electrode what do the the first two digits indicate

this indicates that maximum tensile strength of the weld in psi

what do the numbers in the electrode code E6010 indicate.

this indicates this electrode has a tensile strength of 60,000 psi, and maybe be used in all positions best with DC electrode positive current to provide deep penetration and a thin slag covering

amperage is the most important setting on a SMAW welding machine

true

what is SMAW welding?

using a consumable electrode coasted in flux, and electrical arc is formed between the electrode and base metal. the base metal and the electrode melt to form a weld pool

the weld progresses from top to bottom

vertical welding position

what parameters do welders hav control of during the welding process

welders control current, electrode selection, arc length, electrode angle, electrode motion, and travel speed

The cables that connect the welding power source to the work are known as welding

welding leads

what equipment is required in shielded metal arc welding

welding machine, electrode, workpiece, welding leads, consumable electrode, and a filler rod

the next to last digit on a welding rod indicates

welding position