Emerson Fisher OS2 Instruction Manual page 3

BM1
TyPE OS2
E0564
MECHaniSM BOX (BM1) WiTH 1 ManOMETriC
SEnSing DEViCE (TyPE BMS1)
aPPLiCaTiOn
Overpressure Shutoff (OPSO)
Underpressure Shutoff (UPSO)
Overpressure Shutoff (OPSO) and Underpressure Shutoff (UPSO)
Overpressure Shutoff (OPSO) and Underpressure Shutoff (UPSO)
Overpressure Shutoff (OPSO), Overpressure Shutoff (OPSO) and
Underpressure Shutoff (UPSO)
1. When using one manometric sensing device for both overpressure and underpressure shutoff, make sure that the difference between set pressures falls within the maximum range
shown in Table 2.
2. When using two manometric sensing devices (Types BMS1 and BMS2), the Type BMS1 can only be used for high trip.
Type EZROSX (see Figure 1) is a combination of the
Type EZR regulator and the Type OS2 slam-shut device.
For installation, maintenance and parts information on
the Type EZR portion, refer to Type EZR Instruction
Manual D102600X012.
Type EZHOSX is a combination of the Type EZH regulator
and the Type OS2 slam-shut device. Details related to
installation, maintenance and parts information are listed in
the Type EZH Instruction Manual D103077X012.
Type EZLOSX is a combination of the Type EZL regulator
and the Type OS2 slam-shut device. Details related to
installation, maintenance and parts information are listed in
the Type EZL Instruction Manual D103091X012.
Incorporated in the Type OS2 (up to NPS 6 / DN 150 body
size) valve plug is an automatic internal bypass valve
mechanism, which balances pressures on both sides of the
plug when resetting. Type OSD2 will be used for NPS 8 and
10 / DN 200 and 250 Type OSE slam-shut valves; in this
case the bypass is not internal but external.
TyPE BMS1
TOP-MOUnTED (STanD-aLOnE TyPE OSE VaLVE)
Figure 2. Types of Installation (Mounting on Horizontal Pipeline Only)
Table 1. Applications and Construction Guide (See Figure 2)
MECHaniSM BOX rEQUirED
BM2
TyPE BMS2
(LEFT SiDE)
E0565
MECHaniSM BOX (BM2) WiTH 2 ManOMETriC SEnSing DEViCES
(TyPES BMS1 anD BMS2)
ManOMETriC SEnSing DEViCE rEQUirED
BM1
BM2
The Types OS2 and OSD2 slam-shut devices can be used
for all pressure ranges from 4.02 in. w.c. to 1470 psig /
10 mbar to 101 bar by simply replacing the manometric
sensing device. The Type OS2 can be configured for
OverPressure ShutOff (OPSO), UnderPressure ShutOff
(UPSO), OverPressure Shutoff and UnderPressure ShutOff
(OPSO/UPSO), manual shutoff or remote shutoff.
Mechanism Box (BM1 or BM2)
The mechanism box (BM1 or BM2, see Figure 2) is designed
to close the slam-shut valve. The detection of pressure
variances is sensed by a double-stage trip mechanism (see
Figure 7). The first stage is the detection stage and will only
trip when the system pressure reaches the set pressure of
the manometric sensing device. The second stage is the
power stage and once tripped by the first stage, the closing
spring causes the valve plug to slam-shut and remain
closed until the valve is manually reset. If there are any inlet
pressure variances or vibrations subjected to the second
stage components, they are not transmitted to the first stage
trip mechanism. This unique double-stage trip mechanism
virtually eliminates nuisance tripping commonly found in
other shutoff devices.
Type OS2
TyPE BMS1
(rigHT SiDE)
BMS1 - - - -
BMS1 - - - -
BMS1 - - - -
(1)
BMS1 BMS2
(2)
BMS1 BMS2
(2) (1)
3