Emerson 79U-002, 79E, 79U-003, 79U-006, 79U-036 Operating And Maintenance Instructions Manual

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KEYSTONE FIGURE 79 PNEUMATIC ACTUATOR

OPERATING AND MAINTENANCE INSTRUCTIONS

Operating and Maintenance Instructions for: Figure 79 Pneumatic Actuators (U/E options)

4. If pipelines are hydraulically tested, then the lines should be “blown down” with high pressure air to clear all water, prior to connecting lines to the actuator.

5. Where pipe fitting sealants are used, they should be applied to the male threads only. When applied to female threads, excess compound can be transmitted into the actuator control lines.

Double Acting Actuator

6. Where a system is dependent on Air Filter Equipment, the air filters should be situated in positions that allow easy access to maintain and/or drain.

7. Where pneumatic valve positioners, or pneumatic controllers are fitted to valve actuator assemblies, oil mist lubricated air should not be used unless the manufacturer states specifically that the controllers are compatible with lubricated air.

Single Acting Actuator

Introduction

The Keystone Figure 79 Pneumatic Actuator range is available in three mounting options, as follows: 79U - Keystone Mounting Standard 79E - ISO5211

General Pneumatic Systems Recommendations

All Keystone Pneumatic Actuators are factory lubricated with Molyrace LT grease and, unless the operating environment is extremely poor, do not require re-lubrication. To maintain maximum efficiency with this, or other pneumatic actuators or pressure vessels, we advise that the following basic system recommendations are followed:

1. Where air pipelines are subjected to extremes of temperature, the system should be fitted with air drying equipment.

2. Air control lines should be run to a ‘Recommended Piping Practice’ and should not have “exaggerated” loops which may trap condensate.

3. All pipe ends should be thoroughly cleaned and deburred after cutting to ensure that the pipeline is clear of cuttings.

Note: Figure 79 Actuators are rated for air pressure in the range 40psig (2.75barg) to 120psig (8.3barg) and can withstand a maximum of 150psig (10barg).

Construction

Figure 79 actuators are available in a range of sizes producing up to 27624lb in/ 3121Nm output torque and are designed to be mounted to quarter turn valves either directly or using the correct mounting brackets/adaptors and sizing procedures.

All models are of the opposed piston type. Each piston incorporates a wide toothed rack which engages a one piece drive shaft. The drive shaft is sealbond (TM) treated for maximum protection. The actuator body is of extruded aluminium and is fitted with “Engineered polymer” bearings at the drive shaft locations. Bearing and piston seals are dynamic ‘O’-ring type. The actuator drive is by means of a double keyed female shaft (79U/E). A comprehensive range of double “D” adaptors is available for fitting to both the top and bottom of the output shaft for accessories (top) and valve stems (bottom).

Emerson.com/FinalControl VCIOM-01733-EN 17/04

KEYSTONE FIGURE 79 PNEUMATIC ACTUATOR

OPERATING AND MAINTENANCE INSTRUCTIONS

STANDARD INSTALLATION - DOUBLE & SINGLE ACTING UNITS

These instructions assume that the actuators are installed with the cylinder axis parallel to the axis of the valve bore (In Line).

Single acting actuators are supplied as FAIL-CLOSE units as standard. Reverse acting FAIL-OPEN must be specified at the time of order.

The actuator is mounted as follows:

1. Ensure that the valve and actuator are both in the following positions:

Double Acting units - fully closed Single Acting units - air fail mode

(normallyclosed)

2. Check that the actuator mounting studs are tightly secured in the actuator housing.

3. Install the correct adaptor, if required, into the actuator (fig. 1 - direct mounting) or install the correct coupling and bracketry, if required, to the valve (fig. 2 - bracket mounted option).

See Notes 1 & 2

4. Mount the actuator onto the valve flange or the bracket and secure using a lockwasher and nut on each mounting stud.

5. Before installing the valve/actuator assembly in a piping system, the disc travel should be verified.

6. When installing the valve/actuator assembly into pipeline, ensure that the specific instructions relating to the valve installation are followed. For valves which need to be fitted with the valve in a position other than fully closed, it may be necessary to fit the valve into the pipeline prior to mounting the actuator to the valve. Rubber lined butterfly valves are an example of this.

7. For valves which need to be installed in the pipeline prior to fitting the actuator, ensure that the valve is operated into its failsafe position before mounting the actuator onto the valve.

3. Refit actuator to the top of the valve. (note:on models 036/065/090 adaptors may not be required to be fitted ie directly mounted, in this case simply use the previously unused keyway.)

NOTES

1. The adaptor should be lightly tapped or pressed into the actuator.

2. The coupling should be lightly tapped or pressed onto the valve stem.

Excessive force should not be used (the use of a

lubricant such as Coppaslip is recommended).

FIGURE 1

Lockwasher

FIGURE 2

Lockwasher

Nut

Bolt

Pneumatic

actuator

Valve

Pneumatic

actuator

Adaptor ifrequired

Stud

Nut

Stud

Coupling if required

NON STANDARD INSTALLATION - DOUBLE & SINGLE ACTING UNITS

In circumstances where the actuator is required to be installed in the transverse position i.e. at right angles to the valve bore (Across Line), the actuator must be rotated through 90°. This is achieved in the following manner:

1. Remove the actuator from the valve or the bracket by unscrewing the 4 fixing nuts and withdraw it vertically from the valve.

2. 79U/E Models - remove the double ‘D’ adaptor located in the bore at the bottom of the actuator and re-fit, locating in previously unused keyway of shaft.

Ball

valve

Bracket if required

KEYSTONE FIGURE 79 PNEUMATIC ACTUATOR

OPERATING AND MAINTENANCE INSTRUCTIONS

DISASSEMBLY - DOUBLE ACTING UNITS

Note: Please refer to the relevant exploded

views further on.

CAUTION

Remove all air pressure and observe normal safety precautions including the use of eye protection.

1. Pull off the indicator cap (item 17) from the top of the actuator. If this cap is too tight, light pressure may be applied to the underside via a short length of round bar or a similar blunt ended tool, inserted from the bottom end of the actuator shaft. (Note: levering with a screwdriver is considered to be a potentially dangerous practice and should be avoided.)

`The position relative to the shaft should

be noted to ensure correct position for assembly.

2. Remove both travel stop bolts, if fitted (items 19 to 22, see page 10 for all items)

Loosen endcap fixing screws evenly (item 15)

4. Remove endcaps (item 3)

5. Rotate output shaft (item 5) in a anticlockwise direction to drive pistons apart, and remove pistons (item 2) complete with backing pads/rings - if fitted.

6. Remove circlip (item 12) from bottom bore of actuator.

7. Tap shaft downward and remove. Take care to protect the actuator bore from possible damage from the pinion gear teeth.

8. Remove top bearing (item 9) from the actuator body (the bottom bearing (item 6) will have been removed along with the pinion shaft).

DISASSEMBLY - SINGLE ACTING UNITS

Note: Please refer to the relevant exploded

views further on.

CAUTION

Remove all air pressure and observe normal safety precautions including the use of eye protection. Always ensure that spring return actuators are in fail safe position before attempting any maintenance. Pay particular attention to this requirement when manual operators are fitted. For safety reasons DONOT ‘Air Assist’ Single Acting Pneumatic actuators.

2. Remove both travel stop bolts, if fitted (items 19 to 22, see page 11 for all items).

3. Loosen endcap/spring return housing fixing screws (item 15) evenly until the spring load is relaxed (3 - 5 mm).

Warning: If, after loosening the screws

by 5mm there is still compression on the spring pack, re-tighten the endcap screws and return the unit to the factory for service.

4. Remove endcap/spring housing assemblies.

Warning: Under no circumstances should

the spring retaining bolt be loosened or adjusted without first consulting the factory.

5. Rotate output shaft (item 5) in an anticlockwise direction to drive pistons apart and remove pistons (item 2) complete with backing pads/rings - if fitted.

6. Remove circlip (item 12) from bottom bore of actuator.

7. Tap shaft downward and remove. Take care to protect actuator bore from possible damage from the pinion gear teeth.

8. Remove top bearing (item 9) from the actuator body (the bottom bearing (item

6) will have been removed along with the pinion shaft).

KEYSTONE FIGURE 79 PNEUMATIC ACTUATOR

OPERATING AND MAINTENANCE INSTRUCTIONS

ASSEMBLY - DOUBLE ACTING UNITS

Note: Please refer to the relevant exploded

views further on. Liberally grease actuator bore, pistons and pinion assembly with Molyrace LT lubricant.

1. Coat all ‘O’-ring seals with Molyrace LT lubricant.

2. Output shaft assembly:-

a) Fit the top bearing assembly (item 9) into

the top bore of the actuator body (item 1) with the outer o-ring uppermost.

b) Fit the bottom bearing assembly (item 6)

on to the bottom of the pinion shaft (item

5) with internal o-ring uppermost.

3. Insert pinion shaft assembly from underside of the actuator as shown in fig. 4.

4. Fit internal circlip (item 12) to bottom recess of body to locate the shaft assembly.

Fit ‘O’-ring seals (item 13) on pistons (item 2).

6. Orientate output shaft at 45° ± 2°.

7. Insert pistons (item 2) complete with backing pads(1) (item 18) and backing rings (5), with piston legs on left side of bore (when viewed from the o-ring end of the piston), until racks engages with pinion and then push fully inward, the actuator is now in the fully closed position.

* If no travel stops are fitted proceed to

instruction 12.

8. Turn the pinion shaft anti-clockwise approximately 5° until it is orientated in line with the major axis of the actuator body. The shaft is now in the closed position.

9. Insert CLOSE travel stop bolt (item 19/20) together with sealing nut or lock nut (2)(3), flat washer (2)(3) and sealing washer (2)(3)

until the bolt hits the travel stop cam. Tighten the lock nut.

10. Turn the pinion shaft anti-clockwise through 90° to bring it in line with the center line of the actuator bore, the actuator is now in the open position.

11. Insert Open travel stop bolt (item 19/20) (together with sealing nut or lock nut (2) (3), flat washer (2)(3) and sealing washer (2) (3)) until the bolt hits the travel stop cam. Tighten the lock nut.

12.

Fit ‘O’-ring seals (item 14) to endcaps (item 3) using a light smear of grease.

13. Fit endcaps to body and alternately tighten the endcap screws (item 15) until secure (see recommended torque table).

14. Fit position indicator to top of actuator.

15. Operate the actuator to OPEN & CLOSE positions using compressed air and note the actual positions. If the required travel is not achieved refer to page 12.

NOTES

1 Backing pads are not required on 002/003 models

which have nylon pistons.

2 Lock nuts, flat washers and sealing washers are

only fitted to models 065-180.

3 On models 003/036 the lock nut & sealing nut are

one item.

4 Gear shim is required on models 006 and 012 only. 5 Backing rings and pads are only fitted to models

065/090/180.

Note: Backing pads and rings need only a smear of grease on the undersides before fitting to pistons.

FIGURE 3

Camshaft

Locking nut (Models 065 to 180)

Open position

Actuator body

Open adjustment bolt

Camshaft

Flat washer (Models 065 to 180)

Sealing washer (Models 065 to 180)

Viewed from top of actuator

Close position

Actuator body

Close adjustment bolt

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