Lincoln Electric 250 GXT manual Welding Process, Stick Constant Current Welding, ARC Gouging

WELDING PROCESS

For any electrodes the procedures should be kept within the rating of the machine. For electrode infor- mation see the appropriate Lincoln publication.

STICK (CONSTANT CURRENT) WELDING

Connect welding cables to the "TO WORK” and "ELECTRODE” studs. Start the engine. Set the "Polarity” switch to the desired polarity. The “RANGE” switch markings indicate the maximum current for that range as well as the typical electrode size for that range. The “OUTPUT” Control provides fine adjust- ment of the welding current within the select range. For maximum output within a selected range set the “OUTPUT” Control at 10. For minimum output within a selected range set the “OUTPUT” Control at 5. (“OUT- PUT” Control settings below 5 may reduce arc stabili- ty) For best overall welding performance set the “RANGE” Switch to the lowest setting and the OUT- PUT” Control near the maximum to achieve the desired welding current.

The Ranger® 250 GXT can be used with a broad range of AC and DC stick electrodes. See “Welding Tips 1” included with the Ranger® 250 GXT for elec- trodes within the rating of this unit and recommended welding currents of each.

TIG (CONSTANT CURRENT) WELDING

The Ranger® 250 GXT can be used in a wide variety of AC and DC Tungsten Inert Gas (TIG) welding applications for AC TIG Welding up to 200 amps and DC TIG welding up to 250 amps.

The K930 [ ] TIG Module installed on a Ranger® 250 GXT pro- vides high frequency and shielding gas control for AC and DC GTAW (TIG) welding processes. The TIG Module allows full range output control.

When using the Ranger® 250 GXT for AC TIG welding of alu-

minum the following settings and electrodes are recommended: For AC TIG Welding, the maximum TIG Welding out-

SETTINGS FOR PURE TUNGSTEN

SETTINGS FOR  1% THORIATED TUNGSTEN

put currents on each range setting will be approxi- mately 50% higher than those marked on the name- plate. This is due to the special nature of the AC TIG welding arc. Do not AC TIG weld on the 250 Amp set- ting. The output may exceed the rating of the Ranger® 250 GXT.

WIRE FEED WELDING PROCESSES (CONSTANT VOLTAGE)

The Innershield® electrode recommended for use with the Ranger® 250 GXT is NR®-211-MP. The electrode sizes and welding ranges that can be used with the Ranger® 250 GXT are shown in the following table:

The Ranger® 250 GXT is recommended for limited

“MIG” welding (GMAW - gas metal arc welding). The recommended electrodes are .030” and .035” L-50 and L-56. They must be used with a blended shield- ing gas such as C25 (75% Argon - 25% CO2). The welding ranges that can be used with the Ranger®

250 GXT are shown in the following table:

ARC GOUGING

The Ranger® 250 GXT can be used for limited arc gouging.

Set the Range switch to adjust output current to the desired level for the gouging electrode being used according to the ratings in the following table: