Main Assembly - Doosan DCT10PV Manual De Funcionamiento Y Mantenimiento

ASSEMBLY OF THE DCT10PV AND DCT12PV PICKHAMMERS
GENERAL INSTRUCTIONS
· Before assembly of the breaker, clean all parts thoroughly
and lubricate surfaces with a thin film of recommended
oil – (see lubrication).
· Apply a thin film of O-ring lubricant to all O-rings before
final assembly.
· It is recommended that the assembly of the nozzle (2) be
carried out by the manufacturer or authorised distribu-
tor.
· The existence of a piston air cushion should be determi-
ned. Hold the cylinder vertically and allow the piston to
drop down the bore small diameter first. An air cushion
is present if the piston "bounces", at the bottom of the
cylinder and no metal to metal contact noise can be heard.
If a cushion is not present contact your authorised Doosan
Infracore Portable Power repair centre for advice.
CYLINDER ASSEMBLY
Grip the cylinder (1) vertically nozzle down, in a vice protected
with leather or copper covered vice jaws.
If the cylinder has been disassembled completely rebuild in
the following order.
Lubricate and insert the piston (3) small end first into the
bore.
Locate the pilot diameter of cylinder plug (5) in cylinder bore
and gently tap home using a hide mallet.
Gently spread apart the ends and slide valve ring (4) onto
the cylinder. Locate the split around the valve spring pins
(33) and (34).
Lubricate and replace the O-rings (37) & (36) in their gro-
oves.
HANDLE ASSEMBLY
Position throttle lever (25) in its slot in the handle casting
and align the holes in each part.
Drift or press home the spring pin (26). Check the throttle
lever is free to move easily.
Grip the handle casting (24) in a vice protected with leather
or copper covered vice jaws.
Lubricate and insert throttle valve plunger (26) into position
reduced diameter out of the hole.
Replace the throttle valve ball (27) and spring (28) and retain
in place with throttle valve plug (29), apply loctite 243 to the
threads of the plug and screw home fully.
If the air inlet (30) has been removed, refit it into the handle
casting using Loctite 243 and screw home fully.
Replace the quick release coupling (31).

MAIN ASSEMBLY

Firmly grip the handle assembly (23) vertically in a vice
(protected with leather or copper covered vice jaws).
Position the O-ring (38) and stand the cylinder spring (6)
centrally at the bottom of the handle bore
Carefully slide the cylinder assembly (1) into the cylinder
until the key slot in the handle body (24) aligns with the
mating slot in the cylinder assembly (1). Note: Take care not
to dislodge the cylinder spring off its face in the handle.
Lubricate the slot in the cylinder and replace the anti-rota-
tion key.
Note: Check the handle is free to slide on the cylinder.
Remove the pickhammer from the vice.
Ensure that O-ring (39) is in place on the cylinder (nozzle
end).
52
Lower the cylinder nut (11) onto the handle and cylinder
assembly, engage the handle threads of the nut and tighten
by hand. Fully tighten the Cylinder nut using a (75mm)
spanner until the lock hole in cylinder nut (11) aligns with
a hole in the handle body.
Note: Sight or feel for correct alignment with a suitably sized
wire. Snap the locking ring pin in place. Slide the muffler (9)
together with bearing sleeve (10) down the cylinder until the
muffler retaining lip engages with the groove in the cylinder
nut (11).
ASSEMBLY OF THE FRONTHEAD – SCREW
RETAINER MODELS
Replace the sealing ring (8) in its groove in the cylinder.
Inspect the chisel buffer (13) for wear and replace if necessary,
by sliding a new buffer into the retainer.
Note: Premature failure of the cylinder may occur if a worn
chisel buffer (13) is not replaced. Doosan Infracore Portable
Power recommend that the buffer (13) is checked frequently
during use and replaced if nesseary.
Screw the retainer onto the cylinder assembly.
ASSEMBLY OF THE FRONTHEAD – LATCH
RETAINER MODELS
Grease the latch plunger (22) and plunger spring (21) and
insert them into position in the fronthead (15).
Locate the latch lever (20) with the holes in the fronthead and
press or drift into place the fronthead spring pins (18,19).
Check the operation of the latch.
Slide the fronthead (15) onto the end of the cylinder and align
the bolt hole with the groove machined in the cylinder.
Fit fronthead pinch bolt (16) and secure with nut (17) tighten
to 90 Nm (66.4 lbs.ft) torque.
ASSEMBLY CHECKS
Following service or repair the pickhammer should be checked
for correct operation before being sent back to the job site.
Fit the correct size accessory into the pickhammer and con-
nect to an airline. Using low pressure 2 bar (30psi) check to
ensure the pickhammer is free of air leaks around the inlet
connection and also that the pickhammer does not automati-
cally start to operate without the trigger being depressed.
Increase the air pressure to 6 bar (90psi) and run the tool in
short bursts to check the tools starts and stops cleanly and
without hesitation.
Pickhammer operating frequency should be as given in the
specification table at the end of this manual.