MKS HPS LPV1-25-AC Series, Operation And Maintenance Manual

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HPS HPS
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Square Body LoPro Square Body LoPro
Square Body LoPro Square Body LoPro
Square Body LoPro
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6.3 Clean Installation
Valves are shipped with plastic covers over the ports. These covers should
be left in place until the valve is installed. All Square Body LoPro valves are
cleaned at the factory for direct installation and high vacuum service.
Normal clean assembly techniques should be practiced, as the presence of
airborne particles on the nosepiece seal (9 in Figure 2), the seat (8), or on
the sealing surfaces of the port flanges may result in leakage.
6.4 Flange Care
Care should be taken not to damage the flanges. To help protect the
flanges, the plastic caps supplied with the valve should remain in place until
installation and be replaced when removed from a system. A small scratch
on the flange seal surface of an elastomer sealed flange could prevent a
leak tight seal. Similarly, on valves with CF (metal seal) flanges, scratches
or dents in the knife edge may prevent the flange from sealing. Since the
flanges are integrated with the body, a defective flange could result in
replacement of the body.
When installing the valve, adequate clearance should be allowed between
adjacent components so there is no sliding of seal surfaces against one
another. Flanges that have been assembled for some time may have a
tendency to stick together. Care should be exercised when prying flanges
apart as to avoid damaging their sealing surfaces.