Section 6 - Maintenance - Lincoln Electric 70112 Operating Manual

WARNING
• Have an electrician install and
service this equipment.
• Turn the input power off at the fuse
box, or unplug input lead before
working on equipment.
ELECTRIC
SHOCK
• Do not touch electrically hot parts.
can kill
6.1 Routine Maintenance
General
In extremely dusty locations, dirt may clog the air passages
and cause the welder to run hot. Blow dirt out of the welder
with low-pressure air at regular intervals to eliminate
excessive dirt and dust build-up on internal parts.
The fan motor has sealed ball bearings which require no
service.
Welding Thermal Overload Protection
The REDI-MIG 455 Remote has built-in protective
thermostats that respond to excessive temperature. They
open the wire feed and welder output circuits if the machine
exceeds the maximum safe operating temperature
because of a frequent overload, or high ambient
temperature plus overload. The over temperature light on
the control panel glows if thermostats open. The
thermostats automatically reset when the temperature
reaches a safe operating level. The fan will stay on when
the machines welding and feeding are disabled during
thermostatic overtemperature protection.
6.2 Gun and Cable Maintenance
Cable Cleaning
Clean cable liner after using approximately 150kg of
electrode. Remove the cable from the wire feeder and lay it
out straight on the floor. Remove the contact tip from the
gun. Using an air hose and approx. 350 kPa (50psi)
pressure, gently blow out the cable liner from the gas
diffuser end.
Flex the cable over its entire length and again blow out the
cable. Repeat this procedure until no further dirt comes out.
CAUTION
Excessive pressure at the start may cause dirt to form a
plug.
6.3 Gun Tips and Nozzles
The gun tip should be replaced when worn. Replace with
the correct size for the wire type and diameter. Too large a
tip for the electrode wire will cause arcing within the gun
cable and possible jamming of the wire within the cable .
Remove spatter from inside of gas nozzle and from tip after
each 10 minutes of arc time or as required.
Drive Rolls and Guide Tubes
After every coil of wire, inspect the wire drive mechanism.
Clean it as necessary by blowing with low pressure
compressed air. Do not use solvents for cleaning the idle
roll because this may wash the lubricant out of the bearing.
All drive rolls are stamped with the wire sizes they will feed.
If a wire size other than that stamped on the roll is to be
used, the drive roll must be changed.
IMA 603C

Section 6 - MAINTENANCE

6.4 Input Lead
6.5 Liner Removal, Installation and Trimming
1.
2.
4.
5.
6.
7.
8.
REDI-MIG 455 Remote
Avoiding Wire Feeding Problems
Wire feeding problems can be avoided by observing the
following gun handling procedures:-
1. Do not kink or pull gun cable around sharp corners.
2. Keep the gun cable as straight as possible when
welding or feeding wire through cable.
3. Keep gun cable clean by following maintenance
instructions.
4. Use only clean, rust-free wire. Lincoln Electric wires
have proper surface lubrication.
5. Replace contact tip when the arc starts to become
unstable or the contact tip end is fused or deformed.
If the supply cord is damaged, it must be replaced by a
qualified electrician.
Instructions for MIG Torch
Note: The variation in cable lengths prevents the inter-
changeability of liners between guns. Once a liner has
been cut for a particular gun, it should not be installed in
another gun unless it can meet the liner cutoff length
requirement.
Remove the gas nozzle and contact tip holder.
Lay the gun and cable out straight on a flat surface. Loosen
the liner nut cap located in the brass connector at the
feeder end of the cable and pull the liner out of the cable.
Insert a new untrimmed liner into the connector end of the
cable.
Fully seat the liner bushing into the Euro connector. Tighten
the liner nut cap on the brass cable connector. The contact
tip holder, at this time, should not be installed onto the end
of the gun tube.
With the contact tip holder still removed from the gun tube,
be sure the cable is straight, and then trim the liner to
length. Remove any burrs from the end of the liner.
Screw the contact tip holder onto the end of the gun tube
and securely tighten. Be sure the gas diffuser is correct for
the liner being used.
Tighten the set screw in the side of the gas diffuser against
the cable liner using an Allen key. Do not overtighten.
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