Assembling; Sub-Assembly - Doosan DX140R Shop Manual

ASSEMBLING

Check number of
necessary tools before starting assembly.

Sub-Assembly

Before assembling the parts into valve housing, sub-assemble
the necessary parts.
Main Spool
1. Apply adhesive on the threads of spool.
Fix spring seat, spring, and spool end then fix spool with
wooden vise and tighten spool end.
Torque: 9.8~11.8N•m
Do not apply adhesive excessively. Fix the spool as
near to the spool end as possible so that the
tightening torque does not bend the spool. Excessive
torque may result in spool expansion, causing the
spool to stick and uncontrolled running of the
actuator. Hereafter, heed this caution when applying
adhesive.
Note that the spring in boom 2 spool and the straight
travel spool differ from other parts. Mistakes in
assembly may cause a malfunction of the actuator.
2. Assemble poppet and spring in the spool.
Apply adhesive on the spool thread.
Fix the spool with the wooden vise.
Apply adhesive to the tread of the plug.
Insert the plug which is fitted with an O-ring and back-up
ring.
Torque: 9.8~11.8 N•m.
Assemble spring seat, spring and spool end, and fix spool
end.
Main Control Valve
Page 28
CAUTION
parts, assembling
CAUTION
CAUTION
position, and
SP001029