Lincoln Electric IM637-A manual Operation, Description, Preheat Temperature for Plasma Cutting

B-1 OPERATION B-1

SAFETY PRECAUTIONS

Read and understand this entire section before oper- ating the machine.

WARNING

ELECTRIC SHOCK can kill.

•Do not touch electrically live parts or electrode with skin or wet clothing.

•Insulate yourself from work and ground.

•Always wear dry insulating gloves.

FUMES AND GASES

can be dangerous.

• Keep your head out of fumes.

•Use ventilation or exhaust to remove fumes from breathing zone.

WELDING, CUTTING and

GOUGING SPARKS

can cause fire or explosion

•Keep flammable material away.

•Do not weld, cut or gouge on contain- ers that have held combustibles.

ARC RAYS can burn.

•Wear eye, ear and body protection.

PLASMA ARC can injure

•Keep your body away from nozzle and plasma arc.

•Operate the pilot arc with caution. The pilot arc is capable of burning the operator, others or even piercing safety clothing.

Observe additional Safety Guidelines detailed in the beginning of this manual.

NOTE: All P.C. boards are protected by a moisture resis- tant coating. When the plasma cutter is operated, this coat- ing will "bake off" of certain power resistors that normally operate at high temperatures emitting some smoke and odor for a short time. These resistors and the P.C. board beneath them may become darkened. This is a normal occurrence and does not damage the component or affect the machine performance.

DESCRIPTION

The Pro-Cut 55 is a constant current, continuous control plasma cutting power source. It provides superior and reli- able starting characteristics, cutting visibility and arc stabili- ty. When cutting expanded metal, the Pro-Cut 55 out per- forms the competition due to its quick, clean response to arc transfers. The power supply design provides high transfer- to-cut distances which makes pierce cutting more reliable and with less nozzle wear. The control system has a safety mechanism to insure that the nozzle and electrode are in place before cutting or gouging. This is extremely important due to the high voltages involved.

The Pro-Cut 55 comes standard with an air regulator, coarse air filter, and pressure gauge. There are six different torch and cable systems to choose from: hand-held torch with 25' or 50' cable, machine and robotic torch both with 25' and 50' cable. Consumables are included so that cutting can begin right out of the box. Consumables can also be ordered as individual packages.

The Pro-Cut 55 initiates the plasma arc with a simple, yet reliable, touch start mechanism. This system eliminates many of the failure problems associated with hi-frequency start systems. The Pro-Cut 55 is capable of cutting with nitrogen or air.

The Pro-Cut 55 is controlled by a microprocessor-based control board. The machine performs rudimentary self trou- bleshooting when powered up which aids in field servicing.

PREHEAT TEMPERATURE FOR PLASMA CUTTING

Preheat temperature control is not necessary in most appli- cations when plasma arc cutting or gouging. Preheat tem- perature control may be necessary on high carbon alloy steels and heat treated aluminum for crack resistance and hardness control. Job conditions, prevailing codes, alloy level, and other considerations may also require preheat temperature control. The following minimum preheat tem- perature is recommended as a starting point. Higher tem- peratures may be used as required by the job conditions and/or prevailing codes. If cracking or excessive hardness occurs on the cut face, higher preheat temperature may be required. The recommended minimum preheat temperature for plate thickness up to 1/2" (12.7mm) is 70°F (21.1°C).

PRO-CUT 55