MKS HPS Two-Stage Manual De Servicio página 17

Disassembly and Inspection of Internal Assembly Chapter Two: Servicing an HPS Products Two-Stage
Valve
Disassembly and Inspection of Internal Assembly
WARNING: The internal assembly of the pneumatic valve contains a strong spring. Instructions
below must be followed to avoid personal injury.
To disassemble this unit, the closing spring must be compressed. A standard gear puller can be used
as a spring compression tool. Note that the upper outer edge of the stem guide is a seal surface and
should be protected from the gear puller claws. The following procedure assumes the use of a gear
puller.
1-Put a protective ring over the seal surface on the outer edge of the stem guide.
2-Insert the assembly into the gear puller. Do not touch the bellows with the claws of the puller or
any hard object. Bellows with the slightest damage must be replaced. A spanner must be placed on
the nosepiece to prevent rotation.
3-Tighten gear puller screw slightly to remove the spring load from the bottom of the piston.
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