3.6 CHECKS DURING AND AFTER OPERATION
a. Take reading of dial when set at a minimum (zero)
position,
During operation of the Feeder, check for signs of
leaks, and any unusual operating noises. If present,
b. Add desired wire feed speed to this reading in
turn main power switch at control OFF immediately.
inches-per-minute,
After an operation, repeat the pre-operation checks.
c. Set dial to sum of steps a and b above,
--
3.7 SHUTTING DOWN SYSTEM
Example: If minimum is 55, and the desired wire
When operating during temperature above freezing,
feed speed is to be 185 ipm, set dial at 240.
shut down the system by turning main power switch at
the control OFF. Turn OFF gas and water supplies.
3.4 PRE-OPERATION CHECKS
Disconnect the power cord of the control. When oper-
a. Turn main power switch ON at control.
atingduring temperatures below freezing with a water-
cooled gun, shut down the system as follows:
b. Actuate gun trigger.
a. Turn water supply OFF. Disconnect water supply
hose.
c. Look for leaks at hose connections and around
equipment, and tighten or repair.
b. Place main switch of power source OFF.
d. Look for signs of overheating and burning at
in control to SCRATCH
electrical points, as evidenced by brownish discolor-
c. Set selector switch
ation, smoke, or odor.
START,
d. Depress gun trigger to open water solenoid.
e, Hold gun trigger or jog button depressed for an
interval of 15, 30, or 60 seconds. Measure the amount
e. U s e compressed air to blow out water lines.
of wire output at gun to ascertain actual wire feed speed.
f. Turn main power switch at control OFF,
f. Compare actual wire feed speed with desired speed
set on dial of panel to determine whether calibration of
g. Disconnect power cord of control.
dial potentiometer is necessary. If so, refer to the
M o d e l AHC-B Control manual for calibration
h. Turn shielding gas supply OFF.
instructions.
g. Turn OFF main power switch at Control.
3.8 PRINCIPLES OF OPERATION
This AIRCOMATIC welding system needs only two
3.5 PRE-WELD CHECKLIST
simple hand operations for welding after power is
turned on: (1) setting the wire feed speed dial on the
Before operating the Feeder make sure of the following:
Feeder, and (2) pulling the gun trigger to energize the
a. All connections tight.
circuit, The welding operation is programmed and
electronically controlled by the Model AHC-B Control.
b. Wire in drive rolls properly seated for push gun
Welding wire is power fed, and cooling water and gas
o p e r a t i o n , or drive rolls removed for pull gun
are routed through the Feeder.
operation.
Feeding of the wire is accomplished by a motor and
c. Adjustment knob (Fig. 4) properly set.
drive rolls (Fig, 4). The motor drives the drive rolls
through a pulley and timing belt arrangement within
d. Lever on hub reel (Fig. 5) locked,
the Feeder for pushing wire through a push gun, or it
drives a flexible shaft connected to drive rolls within
e. Proper drag on wire reel (push gun only).
a pull gun which pulls the wire from the reel in the
Feeder, The drive roll housing within the Feeder in-
f. Proper belt tension (push gun only).
cludes a worm gear on an integral bearing-mounted
shaft to which a belt pulley is keyed. This worm drives
g. PUSH- PULL switch (Fig. 4) in proper position
two worm gears, each keyed to a bearing-mounted roll
for the gun being used.
shaft. One shaft end holds a removable conical roll
wire guide fitting, The other holds a grooved roll
h. LOCAL-REMOTE switch (Fig. 4) in proper
fitting. As the motor drives the belt pulley on the worm
position.
shaft, the worm drives a worm gear and roll shaft on
either side of it. The welding wire, gripped between
i. Cover locked.
the conical and grooved drive rolls, is thus pushed
toward the push gun. An inlet guide bushing admits
j. Wire feed speed dial (Fig. 3) properly set.
the wire to the drive roll housing, and after it has
passed through the drive rolls, the wire leaves through
k. Water supply ON and end of drain hose visible.
an outlet guide bushing. It reaches the push gun
through a liner within a casing coupled to the outlet
l. Gas supply ON.
guide bushing and connected to the gun. An adjustment
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