DH Instruments GB-K-152, Руководство по эксплуатации и обслуживанию

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GB-K Gas Booster Package Operation and Maintenance Manual
© 1998 - 2000 DH Instruments, Inc .
Page 14
2. The instrument gas section (high pressure) consists of a small piston and an inlet/outlet
check valve assembly. The small piston moves forward and backward with the air
drive piston. During the suction stroke (backward movement), the outlet check valve
closes and the inlet check valve opens letting instrument gas enter the
compression chamber. During the compression stroke, the inlet check valve closes and
the outlet check valve opens letting compressed gas out of the pump.
The compression ratio of the high pressure piston is 25:1 (for both models).
Maximum output pressure is limited by the instrument gas supply pressure. For
example, with 2 MPa (300 psi) applied, maximum output pressure cannot exceed 2 x 25
= 50 MPa (7 500 psi).
3.1.2 VALVE
The shut-off valve is a ball-type, 90
°
turn valve. It is used to prevent flow of shop drive air to
the pump which shuts off the booster. This valve can be considered a booster
ON/OFF switch.
3.1.3 VOLUME CYLINDER (ACCUMULATOR)
The volume cylinder is a stainless steel chamber with an internal volume of about 50 cc.
Two fittings on the front face of the chamber provide inlet and outlet connections. It is used
to dampen pressure fluctuations during the reciprocating action of the pump and to provide a
reservoir of high pressure compressed gas.
3.1.4 REGULATORS
Three regulators are used in the system for control of the Shop Drive Air, Low Pressure
Outlet and High Pressure Outlet pressures.
All regulators should be adjusted in the increase direction due to hysteresis in the regulators.
Should a regulator be adjusted from a higher pressure to a lower pressure, once gas begins
to flow in the regulator the pressure ultimately set will be lower than that initially set. To avoid
this situation, set the initial pressure below the setpoint then adjust the regulator up to the
final setpoint.
1. The Shop Drive Air Pressure Regulator (10) is constructed of 316 stainless steel and
nylon wetted components. It is a self-venting type regulator with an outlet pressure
control range of 0 to 0.86 MPa (125 psig). Maximum inlet pressure is 1 MPa (50 psig).
The control knob is pulled out to make adjustments; pushed in to lock into position and
prevent accidental changes. It can also be pulled off for tamper resistance.
2. The Low Pressure Outlet Regulator (12) is constructed of aluminum, Viton, stainless
steel and Nylatron wetted materials. It is a non-venting type regulator with an outlet
pressure control range of 0.15 to 1.25 MPa (20 to 180 psig). Maximum inlet pressure is
20 MPa (3 000 psig).
3. The High Pressure Outlet Regulator (7) is constructed of 303 stainless steel, Kel-F,
Buna-N, and Teflon wetted materials. It is a venting type regulator with an outlet
pressure control range of 1.5 to 50 MPa (200 to 7 500 psig) or 2 to 76 MPa 300 to 11 000
psig. Maximum inlet pressure is equal to the maximum outlet pressure.