M20Ht Procedure - Valve Cap Re-Assembly - Siemens Maxum II PD PA AP Service Manual

3. Install three Allen screws (35) each with two Belleville washers (36). Hand tighten screws
but DO NOT compress the Belleville washers (19) in cylinder valve base.
4. With the recessed tip facing up, install the six plungers (14) in the plunger valve body (17).
A clean plunger will fall under its own weight and bounce when dropped into the plunger
valve body.
5. Place a small drop of Krytox 143 AY or equivalent oil between each plunger.
6. Using a pair of tweezers, lift each plunger up and down to allow the oil to flow around a
plunger.
4.5.11

M20HT Procedure - Valve Cap Re-assembly

Note
Before reassembling the valve cap, clean it as described below.
1. Prepare a large syringe with a Tygon tubing adapter installed. Fill syringe with a
recommended cleaning solvent.
2. Using syringe, flush solvent through each port in the valve cap.
Note
When reassembling the valve cap, always install a new Teflon Seal Disc diaphragm (33)
and Nomex Cushion Disc (34) on plunger valve body (17). Do not install the previously
used Teflon Seal (33) and/or Nomex Cushion Disc (34). Before reinstalling seal and cushion
on plunger valve body, remove lint and any dust particles.
3. Place the actuator assembly upright on a clean lint free cloth surface. Refer to Figures 6-1
and 6-2.
4. Position the Nomex cushion disc diaphragm (34) between the three alignment pins on the
plunger valve body (17).
5. Using tweezers hold the Teflon seal disc diaphragm (33) by its edges. Before reinstalling
disc, remove lint, dust and oils by sliding disk between your index and middle fingers.
6. Install Teflon seal disc diaphragm (33) over the Nomex disc cushion diaphragm (34).
7. Align and lower valve cap (32) over the three guide pins of the valve plunger body (17).
Then install valve cap (32) onto the plunger valve body.
8. Install, but do not securely tighten the three Allen screws (35), each with two Belleville lock
washers (36), that secure the valve cap (32) to the valve plunger body (17).
Note
To assure proper tightness in the following two steps, it is recommended to use the torque
wrench (PN 1631005-002) and bit (PN 1631005-701) which are available from Siemens
and can be adjusted over the range of torque measurements listed below.
Maxum II Valves and Oven Components
Service Manual, 10/2018, A5E42019844001
Valves
4.5 Model 20 HT Valve
79