cashco 6987 설치 운영 및 유지보수 - 페이지 2

{카테고리_이름} cashco 6987에 대한 설치 운영 및 유지보수을 온라인으로 검색하거나 PDF를 다운로드하세요. cashco 6987 9 페이지. Back pressure / relief regulator

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10. Basic Regulator- (See Figure 1): Regulator

may be rotated around the pipe axis 360°.

Rec om mend ed po si tions are with spring cham ber

ver ti cal upwards, or hori zon tal. Orient such that

the spring chamber vent hole does not collect

rain wa ter or debris.

11. Regulators are not to be direct buried un der ground.

12. For insulated piping systems, rec om men da tion is

to not in su late reg u la tor.

III. PRINCIPLE OF OPERATION

1. Movement occurs as pressure variations reg is ter

on the diaphragm. The registering pressure is

the inlet, P

or upstream pressure. The range

spring opposes dia phragm move ment. As

inlet pressure drops, the range spring pushes

IV. STARTUP

1. Start with the block valves closed. A bypass valve

may be used to maintain inlet pressure in the

up stream system without chang ing the following

steps.

2. Relax the range spring by turning the adjusting

screw counterclockwise (CCW) a minimum of

three (3) full revo lu tions. This reduces the inlet

(upstream) pres sure setpoint.

3. If it is a "hot" piping system, and equipped with

a bypass valve, slowly open the bypass valve

to pre-heat the system piping and to allow slow

ex pan sion of the piping. Closely mon i tor inlet

(up stream) pres sure, via gauge, to assure not

over-pres sur iz ing. NOTE: If no bypass valve is

in stalled, extra caution should be used in starting

up a cold system; i.e. do ev ery thing slowly.

4. Crack open the inlet (upstream) block valve.

5. Slowly open the outlet (downstream) block

valve ob serv ing the inlet (upstream) pressure

gauge. De ter mine if the regulator is flowing. If

not, slowly rotate the regulator adjusting screw

counter clock wise (CCW) until flow be gins.

6. Continue to slowly open the outlet (down stream)

block valve until fully open.

The maximum inlet pressure is equal to 1.5 times the larger

number of the stated range spring on the name plate, and is

the recommended "upper operative limit" for the sens ing

di a phragm. Higher pressures could damage the di a phragm.

(Field hy dro stat ic tests fre quent ly destroy di a phragms.

DO NOT HY DRO STAT IC TEST THROUGH AN IN STALLED

UNIT; ISOLATE FROM TEST.)

SECTION III

the dia phragm down, closing the port; as inlet

pressure in creases, the dia phragm pushes up

and the port opens.

2. A complete diaphragm failure may cause the

valve to fail closed.

SECTION IV

7. Observing the inlet (upstream) pressure gauge,

ro tate the ad just ing screw clockwise (CW) slowly

until the inlet pressure begins to rise. Rotate CW

until the desired setpoint is reached.

8. Continue to slowly open the inlet (upstream) block

valve. If the inlet (upstream) pressure ex ceeds

the desired set point pressure, rotate the adjusting

screw CCW until the pressure decreases.

9. When flow is established steady enough that both

the outlet and inlet block valves are fully open,

begin to slowly close the bypass valve if installed.

10. Develop system flow to a level near its expected

normal rate, and reset the regu la tor set point by

turning the ad just ing screw CW to increase inlet

pressure, or CCW to reduce inlet pressure.

11. Reduce system flow to a minimum level and

observe set point. Inlet pressure will rise from the

setpoint of Step 9. (Ensure that this rise does not

exceed the stated upper limit of the range spring

by greater than 50%, i.e. 50 - 100 psig (3.4 - 6.9

Barg) range spring, at maximum flow the inlet

pressure should not ex ceed 1.5 x 100 psig (6.9

Barg), or 150 psig (10.3 Barg). If it does, consult

factory.)

12. Increase flow to maximum level if possible. Inlet

(up stream or P

setpoint as necessary at the normal flow rate.

WARNING

) pressure should fall off. Readjust

IOM-6987