Operation - Emerson Tartarini BM6X Series Instruction Manual

BM6X Series

OPERATION

Slam-shut Valve
The BM6X Series slam-shut valve consists of a "wafer" type
valve body, an pilot and a by-pass valve.
The valve body has an off-center butterfly disk that is
mounted eccentrically on the reset shaft.
A lip seal ensures tightness.
The spring thrust, with the additional weight of the eccentric
off-center butterfly disk, ensures punctual and safe closure
under any working conditions.
In addition, the compression of the seal, which is determined
by the pressure, ensures perfect tightness.
6
Off-center butterfly shutter
Figure 6. BM6X Series Operational Schematic
Lip seal
Spring
Controlled pressure
The slam-shut valve can only be opened if the upstream and
downstream pressures are equal.
The Type IT/2V by-pass valve with automatic return makes it
possible to balance these pressures. The valve can only be
opened manually by rotating the pilot reset shaft.
When the controlled pressure lies within the set levels for the
pilot, the latter remains set and prevents rotation of the shaft
while keeping the butterfly disk open.
When said pressure changes beyond the set levels, the
butterfly disk moves to the closure position.
Type IT/2V by-pass valve
Controller
Reset shaft