ESAB PKB 250 User manual

GB
AH 0480
0154 117 201 GB 20110816
PKB™250
PKB™400
Instruction manual

- 2 -

- 3 -
TOCe
Rights reserved to alter specifications without notice.
1 SAFETY 4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2 INTRODUCTION 5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3 TECHNICAL DATA 5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4 INSTALLATION 6. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4.1 Connecting the welding hose 6. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5 OPERATION 7. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6 MAINTENANCE 7. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.1 Daily or as necessary 7. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.2 Replacing the air filter 8. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.3 Replacing the wire guide 8. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.4 Dismantling the motor 9. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6.5 Mounting the motor 10. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
7 TROUBLE SHOOTING 11. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
7.1 Checking for air leaks 11. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
8 ORDERING OF SPARE PARTS 11. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
9 DISASSEMBLY AND DISPOSAL 11. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
ORDER NUMBER 12. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
WEAR PARTS 13. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
ACCESSORIES 17. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

© ESAB AB 1999
- 4 -
bg03d1ea
1 SAFETY
ESAB can provide you with all necessary welding protection and accessories.
WARNING
Read and understand the instruction manual before installing or operating.
Arc welding and cutting can be injurious to yourself and others. Take precausions when welding and
cutting. Ask for your employer's safety practices which should be based on manufacturers' hazard
data.
ELECTRIC SHOCK - Can kill
SInstall and earth the unit in accordance with applicable standards.
SDo not touch live electrical parts or electrodes with bare skin, wet gloves or wet clothing.
SInsulate yourself from earth and the workpiece.
SEnsure your working stance is safe.
FUMES AND GASES - Can be dangerous to health
SKeep your head out of the fumes.
SUse ventilation, extraction at the arc, or both, to take fumes and gases away from your breathing zone
and the general area.
ARC RAYS - Can injure eyes and burn skin.
SProtect your eyes and body. Use the correct welding screen and filter lens and wear protective
clothing.
SProtect bystanders with suitable screens or curtains.
FIRE HAZARD
SSparks (spatter) can cause fire. Make sure therefore that there are no inflammable materials nearby.
NOISE - Excessive noise can damage hearing
SProtect your ears. Use earmuffs or other hearing protection.
SWarn bystanders of the risk.
MALFUNCTION - Call for expert assistance in the event of malfunction.
PROTECT YOURSELF AND OTHERS!
CAUTION
Read and understand the instruction manual before
installing or operating.
CAUTION
This product is solely intended for arc welding.
GB

© ESAB AB 1999
- 5 -
bg03d1ea
2 INTRODUCTION
PKB is an air-operated welding gun with a pneumatic motor incorporated in the
handle. A wire feed unit is fitted in the gun housing.
Different welding speeds can be selected by way of a valve regulating the speed of
the motor.
The welding gun is available in two models, PKB 250 and PKB 400. In the PKB 400
model the outgoing air is used for forced cooling of the gun.
Swan Neck
The gun can be provided with a swan neck which is turnable 360°when the locking
screws in the wire feed unit have been loosened.
The swan neck provides better access when welding in narrow spaces.
Gun Trigger
When the trigger is pressed into its first position the flow relay of the feed unit is
activated and the operating circuit closes.
When the trigger is pressed as far as it will go the air valve is fully opened and the
wire is fed according to the set value.
By slackening the trigger a little during welding, both the wire feed speed and the
welding current will be decreased and the control of the molten pool will be
improved.
Valve for Setting the Wire Feed Speed
The wire feed speed is proportional to the welding current and is set by way of the
speed regulator on the welding gun.
The wire diameter is of vital importance to the welding current. The coarser the wire,
the higher the amperage.
The speed regulator on the PKB is graded 0-9. The index arrow on the left-hand side
of the gun housing indicates the zero position. The knob can be turned some 2.5
turns.
PKB 400 is provided with a hand shield against the heat radiation.
Welding Hose
The welding hose is available in three lengths: 5, 10 and 16 m.
3 TECHNICAL DATA
Welding gun PKB 250 PKB 400
Permissible load at 60% duty cycle
Carbon acid CO2
Gas mixture, Argon (Al electrode)
'
250 A / 26.5 V
200 A / 24 V
400 A / 34 V
280 A / 28 V
Electrode diameter 0.8-1.2 mm 0.8-1.6 mm
Air consumption Max. 280 l/min Max. 280 l/min
Air pressure, max 590 kPa (6 kp/cm2)590 kPa (6 kp/cm2)
Dimensions l x h 210 x 250 mm 210 x 260 mm
Weight 1.2 kg 1.4 kg
GB

© ESAB AB 1999
- 6 -
bg03d1ea
Welding hose A9-250 A9-400
Permissible load at 60% duty cycle
Length: 5 m, 10 m, 16 m 250 A 400 A
Electrode diameter 0.8-1.2 mm 0.8-1.6 mm
Working pressure 490 kPa (5 kp/cm2)490 kPa (5 kp/cm2)
Max. testing pressure 735 kPa (5 kp/cm2)735 kPa (5 kp/cm2)
NB. Make sure the gun motor has the proper working pressure, 490 kPa (5 kp/cm2).
If the pressure is lower the motor will not get the right speed, resulting in too low wire
feed speed and welding current. If the pressure is higher the welding hose will be
exposed to harmful dynamic pressure.
4 INSTALLATION
The installation must be carried out by a professional.
4.1 Connecting the welding hose
SPress the inlet nozzle (a), - selected according to the diameter of the wire - into
the welding hose.
SOpen the wire feed unit on the bobbin side.
SUndo the locking screw (b) on the connecting plate.
SConnect the welding hose (c) to the wire feed unit and tighten the locking screw
on the connecting plate.
SRemove the plastic cover (d) from the gun housing.
SUndo the locking screw (e) and press the other end of the hose into the gun.
STighten the locking screw and fit the plastic cover.
GB

© ESAB AB 1999
- 7 -
bg03d1ea
5 OPERATION
General safety regulations for handling the equipment can be found on
page 4. Read through before you start using the equipment!
Welding Gun PKB 250 and PKB 400
Before starting to use of a new welding gun, or after replacement of the motor, the
gun is to be operated at full air pressure for a short while.
This causes solidified oil and grease in the pneumatic motor to be dissolved, and
ensures uninterrupted service.
6 MAINTENANCE
CAUTION
All guarantee undertakings from the supplier cease to apply if the customer attempts any
work to rectify any faults in the product during the guarantee period.
6.1 Daily or as necessary
Nozzles
SRemove the gas nozzle.
SClean the gas nozzle, the
intermediate nozzle and the contact
nozzle of welding spatter so that the
shielding gas can flow freely and the risk of short-circuiting
is eliminated.
SCheck the gas nozzle for damage and wear. Replace the nozzle if damaged or
worn.
SSelect a contact nozzle according to the diameter of the wire.
SAssemble the parts.
SSpray with welding spray obliquely into the gas nozzle from two directions.
SNB. Never spray straight into the nozzle.
Pneumatic Motor
The motor is provided with an oil nipple for its lubrication.
SLubricate the motor once a week (normal
operation) using the lubrication gun supplied
with the welding gun.
SUse oil, see accessories, page 19.
Feed Unit
STake out and clean the feed unit of the gun as
necessary.
SLubricate the feed unit with some drops of oil.
GB

© ESAB AB 1999
- 8 -
bg03d1ea
6.2 Replacing the air filter
In order to protect the pneumatic motor of the welding gun from impurities the PKB
guns are provided with an air filter.
The filter is fitted in the gun housing in the groove between the two O-rings where
the gas hose is connected.
When a new filter is to be fitted the outer ring must first be removed.
SMake sure the filter is properly fixed before the O-ring is fitted.
6.3 Replacing the wire guide
a Inlet nozzle f Shielding gas inlet
b Compression gland g Compressed-air inlet
c Wire guide h O-rings (inside the tube)
d O-rings i Outlet nozzle
e Inlet end
SUndo the locking screws on the welding hose connections to the wire feed unit
and the gun, then pull out the welding hose.
SPull out the inlet nozzle (a) and screw out the compression gland (b) on the inlet
side and the outlet nozzle (i) on the gun side.
SWithdraw the wire guide (c) from the inlet end. Make sure the o-rings (d) in the
connecting piece come along.
SFit the new wire guide. Stretch out the welding hose and check that the o-rings at
the end of the gun are properly fitted in the grooves. Taper the end of the wire
guide using a file.
SInsert the new guide through the gun connection. If this proves troublesome,
lubricate the end of the wire guide with a little oil or silicon grease.
SFasten the inlet nozzle (i) with screws at the gun end of the welding hose.
SAdjust the length of the guide (c) at the inlet end (e) of the welding hose. Cut the
guide so as to include an excess length of six mm per metre hose, e.g. for a
five-metre welding hose the wire guide is to be cut 30 mm outside the inlet end
of the hose.
SInsert the o-rings round the wire guide and then fasten the compression gland
(b) with screws.
SPress in the inlet nozzle (a).
GB

© ESAB AB 1999
- 9 -
bg03d1ea
6.4 Dismantling the motor
f
12
34
5
6
1. Remove the plastic cover (a) on the gun housing. Undo the locking screw (b) using
an Allen key and remove the welding hose.
Unload the spring (c) and undo the screws (d) holding the contact tube.
Remove the tube.
2. Turn the welding gun upside-down. Wire the feed unit (e) can now be easily removed.
3. Insert a 90 mm long metal rod with a diameter of 2 mm through the hose connection
hole in the gun housing.
Push out the roll pin (f) in the motor shaft which holds the feed roller of the motor
shaft in place.
Remove the feed roller.
GB

© ESAB AB 1999
3
- 10 -
bg03d1ea
4. Remove the hand shield, if any, then gun trigger (m), rubber handle (n) and
contact tube (h).
Check that the three o-rings of the tube (g) come along.
5. Fasten the motor housing (k), in a screw vice or the like, protected by two
wooden jaws, and tighten moderately.
Screw out the left-threaded gun housing (l).
If the motor is rotating in its housing it cannot be dismounted from the housing of
the gun. Then tighten the right-threaded rear (m) a bit harder, using an open
end wrench with a jaw width of 28 mm.
6. Screw out the gun housing (l).
At the same time remove the protective cap (n) of the gasket ring (a transparent
plastic sleeve) from the motor shaft.
Make sure that the sleeve, which is to be put back on the motor shaft, is not
damaged.
6.5 Mounting the motor
12
1. Place the new motor (k) between the wooden jaws
and tighten moderately.
Tighten the rear (m) and provide the motor shaft
with a guide sleeve (o) to protect the gasket ring of
the gun housing during the assembly.
Screw the left-threaded gun housing in place.
2. Loosen the right-threaded rear (m) using an open
end wrench with a jaw width of 28 mm.
Now the gun housing (l) can be turned. Only the
motor shaft is moving. The motor housing is
secured by screws.
Turn the gun housing so that the rear, after having
been tightened, gets into the proper position for
fitting the connection tube.
3. Fit the connection tube (h), the rubber handle (j),
the trigger (i), the protective cap (n) of the gasket ring,
the feed roller (p) of the motor shaft and the wire
feed unit (q)..
The connection tube (h) and the three o-rings (g) are to be fitted very snugly.
Cement the rubber handle using Bostik 292 or the like.
GB