M20 Procedure - Valve Cap Reassembly - Siemens Maxum II PD PA AP Service Manual

Valves
4.4 Model 20 Valve
16.Place a small drop of Krytox 143 AY or equivalent oil between each plunger.
17.Using a pair of tweezers, lift each plunger up and down to allow the oil to flow around a
plunger.
4.4.2.11

M20 Procedure - Valve Cap Reassembly

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 (4)
and Dacron Cushion Disc (5) on plunger valve body (13). Do not install the previously used
Teflon Seal (4) and/or Dacron Cushion Disc (5). 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 5-1
and 5-2.
4. Position the Dacron cushion disc diaphragm (5) between the three alignment pins on the
plunger valve body (13).
5. Using tweezers hold the Teflon seal disc diaphragm (4) 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 (4) over the Dacron diaphragm disc cushion (5).
7. Align and lower valve cap (1) over the three guide pins of the valve plunger body (13). Then
install valve cap (1) onto the plunger valve body.
8. Install, but do not securely tighten, the three Allen screws (3) each with two Belleville lock
washers (2).
Note
To assure proper tightness in the following two steps, it is recommended to use the torque
wrench available from Siemens, part number 1631005-002, which can be adjusted over
the range of torque measurements listed below.
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Maxum II Valves and Oven Components
Service Manual, 10/2018, A5E42019844001