Replacing The Seal Ring Assembly - Fisher 8580 Instruction Manual

Rotary valve

Hide thumbs Also See for 8580:

Instruction manual (24 pages)

Table of Contents

8580 Valve

April 2020

D Install the anti‐blowout ring (key 40) in the groove on the drive shaft (key 10).

D Install the packing follower and, if used, the packing flange.

D Install the packing flange nuts, and tighten them only far enough to stop leakage under normal operating

conditions.

D For oxygen service applications, attach the bonding strap assembly (key 131, figure 4) to the shaft with the clamp

(key 130, figure 4), and connect the other end of the bonding strap assembly to the valve body with a cap screw

(key 35). Secure each cap screw with a hex nut (key 36).

7. Mount the actuator and adjust the closed position of the valve, per the Actuator Mounting section on page 17 of

this manual, before returning the valve to service.

8. When placing the control valve into operation, check around the packing follower for leakage; retighten the

packing flange nuts as required according to accepted bolting procedures.

For valves with ENVIRO‐SEAL packing systems:

1. Isolate the control valve from the line pressure, release pressure from both sides of the valve body, and drain the

process media from both sides of the valve. If using a power actuator, also shutoff all pressure lines to the power

actuator, release all pressure from the actuator. Use lock‐out procedures to be sure that the above measures stay in

effect while you work on the equipment.

CAUTION

When removing the actuator, use a wheel puller to separate the actuator parts from the valve shaft. Do not drive the

actuator parts off the valve shaft because this could damage valve trim components.

2. Remove the actuator per instructions in separate actuator instruction manuals, then remove the cap screws and

nuts (keys 35 and 36). Remove the clamp (key 130, figure 4) if the strap (key 131, figure 4) is used.

3. Loosen the two packing hex nuts evenly to remove spring tension, then remove the nuts.

4. Remove the packing flange and spring pack assembly. The spring pack assembly consists of the spring stack and

packing follower. The spring stack is retained on the packing follower by an O‐ring. Remove the anti‐blowout ring

(key 40) from the driveshaft (key 10). Remove the anti‐extrusion washer, the packing set, and the packing ring.

CAUTION

The valve shaft surface condition is critical in making and maintaining a good seal. If the valve shaft surface is scratched,

nicked, dented, or worn, replace the valve shaft before replacing the packing system.

5. Inspect the existing valve shaft. If necessary, replace the valve shaft as described in the Replacing the Disk, Shafts, or

Bearings section.

6. Install the new packing system components as described in the ENVIRO‐SEAL Packing System for Rotary Valves

Instruction Manual (D101643X012).

7. Install the anti‐blowout ring (key 40) onto the drive shaft (key 10) before installing the packing follower.

8. Mount the actuator and adjust the closed position of the valve, per the Actuator Mounting section on page 17 of

this manual, before returning the valve to service.