Jordan Valve 657M Series Diaphragm Actuator User Manual

Page 2

657M S

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iaphragM

ctuator

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Operation and Adjustment Continued,

The Jordan Valve nameplate indicates a “bench set”

pressure range in addition to a standard diaphragm

pressure range. The “bench set” pressure range indi-

cates the range required to completely stroke the valve

with out any pressure in the valve body, for example

as if the valve were being tested on the work bench.

While In service, however, with the specified pressure

drop applied across the valve, it should stroke over the

standard diaphragm pressure range as indicated on the

nameplate.

Once the control valve has been installed and connect-

ed to the controller, it should be tested for correct travel,

lack of friction and correct action (air-to-open or air-to-

close) to match the controlling instrument. To ensure the

most effective operation, the actuator stem and the valve

plug stem must move freely when responding to the

loading pressure change on the diaphragm.

Disassembly Instructions

Although the following instructions describe how the

657M Diaphragm Actuator can be completely disas-

sembled, when inspection or repairs are required, only

disassemble those parts required to accomplish the job.

Consult Figure 3, and proceed as follows for

disassembly:

Bypass the control valve and exhaust any actua-

tor loading pressure to atmospheric. Discon-

nect the actuator supply line and any

leakoff piping.

Relieve all pressure from the spring by threading

the spring adjuster (key 2) out of the yoke.

To remove the valve body from the actuator,

separate the stem connector (key 21)

and remove the yoke locknut.

Loosen the stem locknuts (keys 13 and 14),

remove the two cap screws and separate the

stem connector.

Loosen the diaphragm case cap screws and

nuts (keys 19 and 20) and remove the

upper diaphragm case.

Remove the molded diaphragm (key 6).

Extract the diaphragm plate and actuator stem

(keys 5 and 3) as an assembly. These parts can

be further separated if required.

Remove the actuator spring (key 1) and spring

seat (key 4).

If necessary, remove the lower half of the dia-

phragm case (key 8) by loosening the

cap screws.

10.

Removing the spring adjuster will complete the

disassembly.

Assembly Instructions

The 657M Actuator can be assembled

in the reverse order of the disassembly

instructions. These additional steps below will

assist with proper assembly and continued

operation.

Apply lubricant to the threads and spring seat

bearing surface of the spring adjuster (See loca-

tion marked “LP” on Figure 3).

Ensure that the spring seats and the lower seat

align properly and rest against the diaphragm

plate.

Use a criss-cross pattern to evenly tighten the

nuts on the casing bolts.

If the stem locknuts were removed during disas-

sembly, install them onto the valve plug stem

and place the travel indicator (key 12) with the

cupped side downward.

Secure the actuator onto the valve body using

the yoke locknut.

Assemble the stem connection as follows

according to the required action:

Mounted on Body with “Push Down to

Close” Valve Plug

When the body is assembled

and the actuator is mounted,

ensure the valve plug is in the

closed

position.

ii.

Once the locknuts are secured

onto the stem, set the travel

indicator disc onto the locknuts

with the cupped portion

facing

downward.

iii.

Raise the valve plug off of the

seat, with the travel specified on

the nameplate, or, pressure the

actuator until the stem

moves down the specified valve

travel.

iv.

Install the stem connector by

clamping

the

actuator

stem to the valve stem.

Raise the indicator disc to the

stem

connector,

using

the locknuts to tighten in

position.