644~645 Pump Governor Instruction Manual

Instruction Manual Form 1321 October 1997

Types 644 and 645

Type 644 and 645 Differential Pressure Pump Governors Scope of Manual This instruction manual provides information on installation, adjustment, maintenance, and parts ordering for the Type 644 and 645 differential pressure pump governors. Refer to separate instruction manuals for information about the valve and other accessories used with these actuators.

Only personnel qualified through training or experience should install, operate, and maintain the Type 644 and 645 governors. If you have any questions about these instructions, contact your Fisher Controls sales office or sales representative before proceeding.

W2265-1 / IL

Description Type 644 and 645 actuators are used in combination with any of several sliding stem valves to automatically control steam-driven boiler feedwater pumps (reciprocating or turbine). The Type 644 or 645 actuator (see figures 1 and 2), when used in combination with one of several push-down-to-close sliding stem valves, forms a pump governor.

Type 644 and 645 actuators may also be combined with push-down-to-open valves to be used as relief governors. Relief governors are used to divert excess pump discharge back to the suction side of the pump.

W2263-1 / IL

W2264-1 / IL

Figure 1. Type 644 Actuator Mounted on easy-e Valve Body

Figure 2. Typical Pump Governor Sectionals

D100302X012

Introduction

Types 644 and 645 CONNECT TO BOILER PRESSURE

EQUALIZING VALVE

A F

B

BOILER PRESSURE

FISHER TYPE 645-ED PUMP GOVERNOR

STEAM SUPPLY E

C RELIEF GOVERNOR

PUMP DISCHARGE

D

14A2729-A A1762 / IL

SUCTION

Figure 3. Typical Installation for a Direct-Acting Governor

WARNING These actuators must be installed, operated, and maintained in accordance with Fisher Controls instructions and all applicable federal, state, and local codes, laws, rules and regulations.

If a leak develops in the system or if any of the equipment is damaged, service is required. Failure to investigate problems immediately may cause a hazardous condition.

Call a serviceman in case of trouble.

Only a qualified person must install or service the actuator.

Installation WARNING To avoid personal injury or property damage caused by bursting of pressureretaining parts, be certain the service conditions do not exceed the casing pressure limit (maximum P across the diaphragm) of 200 psi (13.8 bar). Use pressure-limiting or pressure-relieving devices to prevent service conditions from exceeding this limit.

2

PUMP DISCHARGE

SUCTION 14A2789-A A1763 / IL

Figure 4. Typical Installation for a Relief Governor

The installation site should be protected against damage by external sources such as vehicles. Normal operating temperature range for the Type 644 actuator is from –40 to 180 _F (–40 to 82 _C). For the Type 645 actuator, the range is from –35 to 180 _F (–37 to 82 _C).

Direct Acting Actuators Proceed as follows to install Type 644 and 645 actuators that are used with push-down-to-close valves (Type 644-ED, Type 645-ED). Refer to figure 3.

1. Place the governor in the steam line between a hand operated throttle valve (C) and the steam inlet to the pump. The governor may be installed in any position, as long as the flow is in the direction of the arrow cast on the valve body. However, when used for steam service, the unit should be installed so condensate will drain back into the diaphragm casing and maintain a water seal on the diaphragm.

2. Install a hand-operated throttle valve (E) between the governor and the steam supply line.

3. Run a 1/4-inch control line from the upper diaphragm casing to the side or top of the pump discharge line. Keep the control line away from any nipple, swage, or elbow.

4. Install a lock-shield needle valve (B) and a pressure gauge in this control line.

5. Run a second 1/4-inch control line from the lower diaphragm casing to the boiler steam pressure line.

Install a needle valve (A) in this line. Slope the line toward the governor in order to form a water seal on the diaphragm.

6. Connect the two control lines with an equalizing line in which a needle valve (F) has been installed.

Types 644 and 645 The equalizing line helps prevent damage to the diaphragm when the system is started up.

Table 1. Maximum Static Casing Pressures Diaphragm Casing Material

Proceed as follows to install Type 644 and 645 actuators that are used with push-down-to-open valves (Type 644-EDR, Type 645-EDR).

1. Place the governor in the steam line. It may be installed in any position as long as the flow is in the direction of the arrow cast on the valve body. However, when used for steam service, the unit should be installed so condensate will drain back into the diaphragm casing and maintain a water seal on the diaphragm.

2. Run a bypass line from the pump’s discharge line to the suction line of the pump. In this line, install a hand-operated throttle valve (D).

3. Run a 1/4-inch control line from the upper diaphragm casing to the pump discharge line. Install a needle valve (B) in this line.

4. Extend a second 1/4-inch control line from the lower diaphragm casing to the boiler steam pressure line.

Place a needle valve (A) in this line.

5. Connect the two control lines with an equalizing line in which a needle valve (F) has been installed.

Type Number

Steel

ANSI Classes 125 & 250

ANSI Classes 150, 300 & 600

644

300 psig

600 psig

645

500 psig

1000 psig

Valve Body Ratings

Reverse Acting Actuators

Cast Iron

Startup Proceed as follows to startup direct acting actuators (Type 644-ED, Type 645-ED). See figure 3.

1. Close all valves except the bypass valve (D).

2. Open the equalizing valve (F).

3. Open the needle valve (B) in the pump discharge line approximately 1/2 turn.

4. Open needle valve (A) in the pressure control line and close equalizing valve (F).

5. Open valve (C) that is downstream of the governor.

Close bypass valve (D).

6. Slowly open valve (E) which is upstream of the governor.

7. To increase the discharge pressure, if it is too low, turn the lower spring seat (key 19, figures 5 and 6) clockwise into the yoke.

8. If the discharge pressure is too high, slightly open needle valve (B). If the pressure does not fall to the desired setting, turn the lower spring seat counterclockwise out of the yoke.

9. Open or close lock-shield needle valve (B) to a point where a very slight movement of the valve stem (approximately 1/64-inch) is noticeable with each stroke of the pump. Greater stem movement will result in erratic operation and shorten the life of the diaphragm.

Overpressure

To startup reverse acting actuators (Type 644-EDR, Type 645-EDR) proceed as follows. See figure 4.

WARNING

1. Close all valves except the bypass valve (D).

2. Open the equalizing valve (F).

Overpressuring any portion of this equipment may cause damage to the governor parts, leaks in the system, or personal injury due to bursting of pressure-containing parts.

3. Open valve (A) that is in the boiler pressure control line.

To avoid overpressure, provide an appropriate overpressure protection device to ensure that none of the limits listed in table 1 will be exceeded.

5. Valve (C), downstream of the governor, should now be opened. Close bypass valve (D).

Check the system for damage after any overpressure condition.

4. When the pump has built up the discharge pressure, open valve (B) that is in the discharge pressure control line. Close equalizing valve (F).

6. Slowly open upstream valve (E).

7. To increase the discharge pressure if it is too low, turn the lower spring seat (key 19, figures 5 and 6) clockwise into the yoke.

3

Types 644 and 645 8. If discharge pressure is too high, slightly open equalizing valve (F). If the pressure does not fall low enough, turn the lower spring seat counterclockwise out of the yoke.

9. Open or close valve (B) to a point where very slight movement (approximately 1/64-inch) of the stem is noticeable with each stroke of the pump. Greater stem movement will result in erratic operation and shorten the life of the diaphragm.

Maintenance Actuator parts are subject to normal wear and must be inspected and replaced when necessary. The frequency of inspection and replacement depends on the severity of service conditions. Because of the care Fisher Controls takes in meeting all manufacturing requirements (such as heat treating and dimensional tolerances), use only replacement parts manufactured or furnished by Fisher Controls.

WARNING Adjustment No adjustment is required other than that described in the procedure for putting the governor into operation.

If it is necessary to change the setting, turn the lower spring seat clockwise into the yoke to increase the pressure setting. Turn the lower spring seat counterclockwise, out of the yoke, to decrease the pressure setting.

Principle Of Operation Figure 3 shows Type 645-ED being used to directly maintain a differential setting between the pump discharge pressure and the boiler steam pressure in a boiler feedwater system.

If pump discharge pressure increases, the change is registered on the top of the actuator diaphragm. The increased pressure forces the diaphragm and valve plug downward. With the steam supply thus restricted, less steam reaches the pump. This causes the discharge pressure to drop so that a difference between the discharge pressure and the boiler pressure will return to the desired differential setting.

In figure 4, Type 644-EDR is being used as a relief governor maintaining a differential pressure between the boiler and pump discharge.

An increase in the pump discharge pressure is registered on the top of the actuator diaphragm. The increased pressure forces the diaphragm and valve plug downward. Since this governor is reverse acting, this action opens the valve and allows the excess pump discharge to flow to the pump suction line. The pump discharge pressure drops and the difference between the boiler pressure and the pump discharge pressure returns to the desired level.

4

Avoid personal injury or property damage from sudden release of process pressure or bursting of parts. Before performing any maintenance operations: D Disconnect any operating lines providing air pressure, electric power, or a control signal to the actuator. Be sure the actuator cannot suddenly open or close the valve.

D Use bypass valves or completely shut off the process to isolate the valve from process pressure. Relieve process pressure from both sides of the valve.

Drain the process media from both sides of the valve.

D Vent the power actuator loading pressure and relieve any actuator spring precompression.

D Use lock-out procedures to be sure that the above measures stay in effect while you work on the equipment.

WARNING To avoid personal injury and equipment damage, isolate the pump governor from all pressure before beginning disassembly. The pump governor can be isolated by throttling valve (D) and closing the shut-off valves (A, B, C and E).

Directions for lubricating the packing and disassembling the actuator are given below. Refer to figures 5 and 6.

Lubricating the Packing Keep the packing box nuts (key 9) tightened firmly in order to prevent leakage. However, do not over-tighten these nuts. This increases friction and results in unsatisfactory service.

Types 644 and 645 To lubricate the packing, turn the lubricator (key 27) 1/2 turn every other week. If the unit is operating on high pressure or temperature, the gland will need lubricating more often.

4. Reconnect the stem and diaphragm rod.

5. Turn the lower spring seat counterclockwise out of the yoke to take up the slack in the diaphragm, then finish tightening the diaphragm casing cap screws and hex nuts.

Disassembly 1. Remove the control line from the upper casing.

2. Relieve spring compression by turning the lower spring seat (key 19) clockwise into the yoke.

3. Disconnect the stem (key 22) and the diaphragm rod (key 14) by unscrewing the locknuts (key 31).

CAUTION To avoid damage to the valve plug and seating surface, do not turn the stem while the valve plug is seated.

4. Unscrew hex nuts (key 9) and remove the packing box flange (key 7) and the packing follower (key 6).

5. Remove cap screws (key 23) and hex nuts (key 24) and lift off the upper diaphragm casing (key 1).

6. Lift off the upper diaphragm head (key 29). Pull the diaphragm (key 3), lower diaphragm head (key 13), and the diaphragm rod (key 14) out of the lower diaphragm casing (key 2). (A travel stop or bearing retainer, key 26, figure 5, may also be present between the lower diaphragm head and locknut.) Do not change the position of the lower diaphragm head and locknut (key 15) on the diaphragm rod because they are set to give the proper clearance for valve travel.

7. With a wire hook pull the packing (key 11, figure 5; key 12, figure 6) from the bottom of the lower diaphragm casing. Remove the spacer (key 5) and the upper piece of packing (key 12, figure 5; key 11, figure 6) in the same manner.

Parts Ordering Each actuator has a serial number stamped on the nameplate. Always mention this number when corresponding with your Fisher Controls sales office or sales representative regarding technical information or replacement parts. Also, reference the complete 11-character part number of each needed part as found in the following Parts List.

Parts List Key 1 2 3*

4

Reassembly 1. Replace the diaphragm rod and slide the new packing on it, from the bottom, in the following order: uppermost packing (key 12, figure 5; key 11, figure 6), spacer (key 5), lower packing (key 11, figure 5; key 12, figure 6), and packing follower (key 6). Replace hex nuts (key 9).

2. Place a new diaphragm on the lower diaphragm head. Apply a small amount of gasket cement around the diaphragm rod.

3. Put the upper diaphragm head onto the diaphragm.

Set the upper diaphragm casing onto the lower casing, tightening the cap screws and hex nuts finger tight only.

*Recommended spare parts

5

6

7

Description Upper Diaphragm Casing Lower Diaphragm Casing Diaphragm Neoprene Type 644 Size 1 Size 2 Size 3 Type 645 SST Type 644 only Size 1 Size 2 Size 3 Yoke, cast iron Type 644 2-1/8 inch Boss, w/o 304 2-13/16 inch Boss, w/o 304 2-1/8 inch Boss, w/304 Type 645 Lantern Ring, 316 SST Type 644, graphite packing Spring, 316 SST Type 644, TFE packing Spring/Spacer, 316 SST Type 645 TFE packing Graphite packing Packing Follower, 316 SST Type 644 Type 645 Packing Box Flange, steel, Cd pl Type 644 Type 645

Part Number See following table See following table

1F939502192 1F939302192 1F939602192 0F092802162

1J8430X0012 1U5770X0012 1H5791X0012

2F942219042 3F942419042 1U9572X0012 3F944319042

1F364135072

1F125437012

1F125537012 1J962335072 1E943935072 1E944335072 1E943724102 1E944223072

5

Types 644 and 645

PARTS NOT SHOWN 28 DF9840-A / DOC 40A5422-B / DOC

SIZE 3

Figure 6. Type 645 Actuator Assembly

Figure 5. Type 644 Actuator Assembly Key 8

9

10*

11*

12*

13

14

15

6

Description Stud Bolt, steel, Cd pl (2 req’d) Type 644 Type 645 Hex Nut, steel, Cd pl (2 req’d) Type 644 Type 645 Bushing, SST Type 644 Packing Box Ring, SST Type 645 Packing, Type 644 (4 req’d) Graphite Packing Ring, Type 645, (4 req’d) Graphite Packing Set, Type 645 TFE Packing, Type 644 (3 req’d) Graphite TFE Packing Ring, Type 645 (3 req’d) Graphite Lower Diaphragm Head, cast iron Type 644 Size 1 Size 2 Size 3 Type 645 Diaphragm Rod, SST Type 644 Type 645 Hex Jam Nut, steel, Cd pl Type 644 (2 req’d) Type 645 (4 req’d)

Part Number

Key 16

1E944131032 1E944431032 17 1E944024112 1E944524122 1E943835012

18

1E839135012 19 1F3370X0322 1E3190X0222

20

1R290201012 1V3160X0022 1C752601012 20 1V3802X0022

1F938619042 1F939819042 1F940019042 1F940519042 1F939135162 1F940235162 1A680324122 1A353724122

21

Description Part Number Yoke Lock Nut, steel Type 644 1E793023062 Type 645 1E807423062 Washer, steel (not used on push-down-too-close valves) Type 644 Sizes 1 and 2 1D716328982 Type 645 (2 req’d) 1E658828982 Upper Spring Seat, steel, Cd pl Type 644 1F939724102 Type 645 1F940424102 Lower Spring Seat, steel, Cd pl Type 644 1F938824102 Type 645 1F939424102 Spring, steel Type 644 Compression Rate: 314 lb.

1F945527032 609 lb.

1F945627032 940 lb.

1F945727042 Spring, steel (continued) Type 645 Differential pressure range: 14-24 psi 1F714427112 24-35 psi 1F176727032 35-47 psi 1F176827092 47-59 psi 1F176927092 59-62 psi 1E792327092 62-85 psi 1F714327092 85-99 psi 1E795327082 99-119 psi 1E792427082 119-140 psi 1E795427082 140-162 psi 1E793327082 Adjusting Screw, brass 1F939214012

*Recommended spare parts

Types 644 and 645 Key 1 Upper Diaphragm Casing TYPE SIZE NUMBER 644 645

NEOPRENE DIAPHRAGM

SST DIAPHRAGM

Cast Iron

Steel

Steel

1

2F940719022

2F940122012

2J8664X0012

2

2F941419022

2F942122012

1U5768X0012

3

2F941019022

2F942022012

2H5788X0012

---

1K925019022

0F090322012

---

Key 2 Lower Diaphragm Casing TYPE SIZE NUMBER 644 645

NEOPRENE DIAPHRAGM

SST DIAPHRAGM

Cast Iron

Steel

Steel

1

2F941219022

2F941922012

2J8665X0012

2

2F941319022

2F941522012

1U5769X0012

3

2F941119022

2F941822012

2H5789X0012

---

2F941619022

2F941722012

---

10A8251-A / DOC

Key 29

Figure 7. Equalizing Piping Configuration Key 22

23

24

25 26

27

28*

29

Description Connecting Rod, steel, Cd pl Type 644 Boss size: 2-1/8 inch 2-13/16 w/o 304 Type 645 Cap Screw, steel Type 644 Size 1 (12 req’d) Size 2 (8 req’d) Size 3 (12 req’d) Bolt Stud, steel, Type 645 (8 req’d) Nut, steel, Cd pl Type 644 Size 1 (12 req’d) Size 2 (8 req’d) Size 3 (12 req’d) Hex Nut, steel, Type 645 (16 req’d) Set Screw, steel Bearing Retainer, steel Type 644 Travel Stop, steel Type 645 Pipe Plug, steel Cd pl w/o Lubricator Lubricator, SST w/Lubricator Lubricator/Isolating Valve, SST (Type 645 only) Male Adaptor, TFE (with TFE packing) Special Washer (Type 645 with TFE packing) Upper Diaphragm Head Type 644 Size 1, steel Size 2, cast iron Size 3, cast iron

*Recommended spare parts

Part Number

1F939024102 1F938924102 1F940324102

1A685724052 1A444024052 1A444024052

30 31

32

1B109531012

33 34

1A346524122 1A413224122 1A413224122

35

1A440924112 1C345128992

37

36

38* 1F940925022 39* 1A625625022 1A767524662

40 41 42

EMEX1F9 EMEX1F10

43 44 45

1F124801012 1F125136042

1F938724092 1F940619042 1F939919042

47

Description Upper Diaphragm Head (continued) w/SST Diaphragm (Type 644) Size 1, steel Size 2, steel Size 3, steel Type 645, cast iron Bearing, steel Hex Nut, steel, Cd pl Type 644 Boss Size 2-1/8 inch Boss Size 2-13/16 inch & Type 645 Hex Nut, steel, Cd pl, Type 644 only Boss Size 2-1/8 inch Boss Size 2-13/16 inch Name Plate, aluminum Drive Screw, steel pl (4 req’d) Hex Nut, steel Type 644 only Needle Valve, carbon steel (3 req’d) Special Washer, SST Type 644 only Female Adaptor, TFE (TFE packing) Type 644 only Wiper Ring, felt Type 644 only Nipple, SST (2 req’d) Tee, steel (2 req’d) Nipple, SST, Type 644 (5 req’d), Type 645 (4 req’d) Union, steel Elbow, carbon steel pl Nipple, SST Type 644 Size 1 Size 2 (2 req’d) Size 3 Type 645 Stem Disk, SST Boss Size 2-1/8 inch w/304 only

Part Number

1J8431X0012 1U5771X0012 1J8429X0012 0F091219042 1D361399012

1A346524122 1A413224122 1A680324122 1A353724122 1F940811992 1B877728992 1A346524122 1A423299012 1F125236042 1F124401012 1J872606332 1B218826232 1B860628992 1C488226232 1B860799012 1B860828992

1C559926232 1D239726232 1N584226232 1N624026232

10A0038X012

7

Types 644 and 645

Fisher, Fisher-Rosemount, and Managing The Process Better are marks owned by Fisher Controls International, Inc. or Fisher-Rosemount Systems, Inc. All other marks are the property of their respective owners.

EFisher Controls International, Inc. 1976, 1997; All Rights Reserved

For information, contact Fisher Controls: Marshalltown, Iowa 50158 USA Cernay 68700 France Sao Paulo 05424 Brazil Singapore 128461 8 Printed in U.S.A.