Jordan Valve Mark 57 Series – Externally Piloted Regulator - Manual (Page 2)

following steps are recommended:
1.
Close the inlet shutoff valve.
2. Allow pressure to bleed off through the down-
stream piping. Do not attempt to reverse the flow
through the valve by bleeding pressure from the
upstream side of the valve.
3. When the pressure gauges indicate that all pres-
sure has been removed from the system, close the
outlet shutoff valve, and the valve may be serviced.
Note: refer to the drawing at the end of this docu-
ment for description and proper orientation of parts.
Pilot Valve
The pilot valve is a Jordan Mark 50 Back Pressure Regu-
lator. For maintenance, refer to the Mark 50 Installation
& Maintenance sheet.
Main Valve
It is necessary to remove the main valve from the line
only if the main valve seats must be replaced, inspected
or adjusted. All other operations can be performed with
the valve in the line and without disturbing the stroke
adjustment.
To Repair Main Valve
The sliding Gate Seats of Jordan Valves are lapped to
light band flatness. Maintaining such tolerances is of
paramount importance for your assurance of excellent
control and tight shutoff. DO NOT use metallic objects in
removing the seats. Care in handling is imperative.
To Remove Main Valve Seats
1. Remove the pilot tubing and the pilot valve with the
mounting nipple.
2. With the main valve out of the line, remove the
bolts securing the main valve cap to the main valve
body and lift the cap straight up.
3. Lift the disc from the plate and place on a clean
surface with the seating side up.
4. Place the valve body on a side. Hold one hand over
the plate to receive it and tap lightly on the back
of the plate with a soft, blunt object; push the pate
out evenly. Place the plate on a clean surface seat-
ing side up.
To Remove Main Valve Diaphragm
and Disc Pin
1. Remove the bottom cap. The spring and spring
guide will come out with it.
2. Disconnect the loading pressure tubing from the
upper case, remove the case bolts and upper case.
Trouble Shooting
The first step in trouble-shooting a piloted back pressure
regulator is to classify the action of the controlled pres-
sure into one of the following categories:
A. Over Pressure - Controlled pressure too high; not
enough flow or no flow through valve.
B. Under Pressure - Valve will not close or controlled
pressure decreases after valve closes.
C. Pressure Fluctuates - Controlled pressure rises and
falls, will not settle out under low relief loads.
The next step is to determine what could cause the trou-
ble. The third step is to locate and remedy the cause by
the process of elimination. Make no assumptions and
check the easy ones first. The guide below lists the con-
trolled pressure action, common causes and procedure
for checking each cause.
Controlled Pressure Action OVER PRESSURE

Valve undersized for application. Check capacity
required and valve capacity.
 Line strainer screen clogged. Blow down strainer or
visually check that it is clear.
 Incorrect setting on range spring. Vary the setting
and check response.
 Main valve diaphragm ruptured. See section on
Main Valve Maintenance.
Controlled Pressure Action UNDER PRESSURE

Incorrect setting on range spring. Vary the setting
and check response.
 Pilot Valve or main valve seats leaking. Close inlet
shut-off valve. Close outlet shut-off valve and re-
move loading pressure tubing. Both pilot valve and
main valve are closed. Barely open inlet shut-off
valve until fluid issues from pilot valve port, then
close inlet valve. Flow from pilot valve port should
cease. If it does not, the pilot seats are leaking. If
fluid issues from main valve port, the main valve
seats are leaking.
 By-pass shut-off valve leaking. During period of
leakage, close inlet shut-off valve, observe pressure
gauge.
 Bleed port in main valve clogged. Remove Upper
Bonnet to gain access bleed port and clean bleed
port. Follow instructions in section TO REMOVE
MAIN VALVE DIAPHRAGM.
Controlled PRESSURE FLUCTUATES

Valve oversized. Check capacity required and valve
capacity.
Maintenance
Caution: Make certain that there in no pressure in
the valve before loosening any fittings or joints. The
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