HDK-MT350_EN_06
45
Replacing inlet valves V1 / V2
Warning - injury hazard posed by backpressure!
When relieving pressure, swollen seals can cause backpressure. The
outflow of compressed air can cause injuries.
Only slacken off screw connections and loosen components with great
care and slowly.
Allow the system to decompress over night (several hours) before
carrying out maintenance work.
► Depressurise the dryer and shut it down (see page 35).
► Undo the cylinder screws (10).
Take care during the next step!
There is a compression spring (7)
behind the flange (9). When removing
the flange, the spring may relieve and
jump out of the holder.
► Remove the flange (9) carefully.
► Pull out the compression spring (7)
and piston (4).
► Check the valve seat (2) for
damage, replace if damaged.
► Carefully grease O-ring (3) and fit in
valve seat.
► Fit valve seat (2) in valve plate (1).
Inlet valve
► Insert piston (4) in the hole while pressing the piston ring (5) together by
hand so that the piston can be moved a little in the housing.
Caution - functional reliability!
Ease of movement is important for the trouble-free function.
► Fit new compression spring (7) in piston (4).
► Remove old O-ring from flange.
► Push the new, greased O-ring (8) onto the flange (9).
► Carefully insert the flange into the hole against the spring force.
Note:
Do not force the flange into the hole otherwise the O-ring may shear
off.
► Apply lubricant to the thread of the hexagon socket head cap screw.
► Screw in the socket head cap screws and tighten crosswise in stages
(tightening torque 30
+5
Nm).
► Check that all screw connections are tight.
► If no other maintenance work is to be carried out: Restart the dryer (see
page 36).
Recommended lubricant: Vaseline