Badger Meter Research Control Valve - Manual (Page 9)

Bellows
General
On applications involving toxic gases, radioactive
materials and others where the primary seal at the valve
stem is critical, a metal bellows stem seal can be used
to preclude leakage as long as the integrity of the
Removal of Assembly from Valve
1. Remove the valve from the process line and hold
valve in a bench vise clamped on the body ends.
bellows remains intact. Extreme care should be
exercised in removing and/or installing the Bellows Seal
Assembly to preclude damage. The metal thickness of
the low pressure bellows is only 0.005” to 0.007” thick,
and excess torsion will twist and deform the convolutions,
damaging the assembly.
2. On air-to-open valves apply air pressure to diaphragm
to raise innervalve off seat. (Not necessary for air-to -
close valves).
FIG. 15 FIG. 16
FIG. 17
FIG. 18
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