Lincoln Electric IM812-A manual Procedure AT END of Coil

Models: IM812-A

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B-6

OPERATION

B-6

 

 

 

WARNING

CYLINDER may explode if damaged.

• Keep cylinder upright and chained to support.

Keep cylinder away from areas where it may be damaged.

Never lift welder with cylinder attached

Never allow welding electrode to touch cylin- der.

Keep cylinder away from welding or other live electrical circuits.

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a. Shut off power source if a Remote Output Control Option or internal contactor is not used.

b. Cut the end of the electrode off at the gun end. Do not break it off by hand since this puts a slight bend in the wire and makes it difficult or impossible to pull it back through the nozzle.

c. U n c o u p l e t h e g u n c o n d u c t o r c a b l e f r o m the LN-35.

d. Lay the cable out straight.

e. Using pliers to grip the wire, pull it out of the cable from the connector end. Do not pull it from the gun end.

f.Put the conductor cable back on wire drive unit after the electrode has been removed.

g.Load a new coil of wire and feed it through the cable as described in Loading Electrode Section.

WARNING

ARC RAYS can burn.

Do not touch metal por-

tions of the LN-35 lead Clamp when welding power source is on.

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a. Cut the electrode within approximately 3/8”(9.5mm) of the end of the contact tip for solid wire and within approximately 3/4”(19.1mm) of the extension guide for cored wire.

b. Position electrode over joint. End of electrode should be slightly off the work.

c. Lower welding helmet, close gun trigger, and begin welding. Hold the gun so the contact tip to work distance gives the correct electrical stickout as required for the procedure being used.

NOTE: If the arc voltage is not within the proper procedure range adjust the power source output control. (The CC mode WIRE SPEED setting should not be changed from the preset procedure value for the proper arc voltage.)

d. To stop welding, release the gun trigger and then pull the gun away from the work.

PROCEDURE AT END OF COIL

When the wire on the reel is used up, the following procedure is to be followed for removing the old wire from the gun cable and loading a new reel.

OPEN ARC WELDING WITH A CONSTANT CURRENT (formerly variable voltage) POWER SOURCE

Although a constant voltage (CV) power source is recommended for Innershield® and gas metal arc welding (GMAW), satisfactory general purpose welding may be obtained using the LN-35 with a constant current (CC) power source for non - c r i t i c a l c o m m e r c i a l q u a l i t y m i l d s t e e l welding applications.

While welding with a continuously fed electrode, weld current variations are continuously taking place. There are many causes for these variations, but predominantly they occur due to changes in electrical stickout (operator hand movements, nozzle tip contact variations, etc.) and the dynamic metal transfer characteristics of the process or procedure being used (short arc, globular transfer, etc.).

When using a CV power source, these current variations have essentially no effect on the welding arc stability since CV power sources can provide a wide range of weld current levels with virtually no change in average arc voltage. These “flat slope” CV power sources, therefore, provide the arc power required to produce the best welding characteristics and ease of operation for most open arc, constant wire feed speed, welding processes.

LN-35

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Lincoln Electric IM812-A manual Procedure AT END of Coil