Jordan Valve Mark 75 Series – Wafer Style Control Valve - Manual (Page 4)

Changing Valve Action
The action of a Sliding-Gate Valve may be changed from
DIRECT ACTING to REVERSE ACTING, or vice versa, by
rotating the Disc (27) on the Plate (28) 180°. Check the
valve stroke and orifice alignment and adjust, if required,
as outlined in the Valve Stroke Adjustment section.
Ordering Spare Parts
Use only genuine Jordan Valve parts to keep your valve
in good working order. So that we can supply the parts,
which were designed for your valve, we must know ex-
actly which product you are using. The only guarantee to
getting the correct replacement parts is to provide your
Jordan Representative with the valve serial number. This
number is located on the valve identification tag. If the
serial number is not available, the parts needed for your
valve might be determined using the following informa-
tion: Model Number, Valve Body Size, Seat Material and
Cv Rating, Spring Range and Set Point, Trim Material, Part
Name - Number and Quantity.
NOTE: Any parts ordered without a valve serial number
that are found to be incorrect are subject to up to a mini-
mum 25% restock charge when returned.
-4-
2. For Direct Acting (Air to Close) Valves; Turn the
Actuator Stem (14) counterclockwise until the
Range Springs (10) are slightly compressed. This
insures that the Actuator Stem is in its fully upward
position. To confirm that the Actuator Stem is fully
stroked up, check that it cannot be easily rotated
without a wrench.
3. For Reverse Acting (Air to Open) Valves; Apply an
air pressure of approximately 5 psi above the maxi-
mum range pressure (ex. 20 psi for 3-15 psi range)
to the actuator. This insures that the Actuator Stem
(14) is in its full downward position. To confirm that
the Actuator Stem (14) is fully stroked down, check
that it cannot be easily rotated without a wrench.
4. Check the alignment of the orifices in the Disc (27)
and Plate (28). The orifices must be in the open
position and in perfect alignment. If the orifices are
not in proper alignment, loosen the Stem Locknut
(31) and thread the Stem Adapter (22) into, or out
of, the Actuator Stem (14), which will move the Disc
(27) up, or down, on the Plate (28).
5. After the proper alignment has been obtained,
tighten the Stem Locknut (31) against the end of
the Actuator Stem (14). Recheck the seat adjust-
ment. Repeat Step 4 if necessary.
6. Adjust the spring preload if necessary. See the
Spring Adjustment section.
Spring Adjustment
The signal range is preset by Jordan Valve; however,
when the valve is installed this range may shift slightly
due to pressure drops across the valve. Additionally,
preload adjustment may be required after one of the
previous maintenance procedures. Note: ATO 3 – 15
psig rated valves are bench set at the factory at 5 – 17
psig. Please insure that any I/P utilized with this control
valve is capable of 17-psig output to ensure full valve
travel. If desired, the range may be changed to suit your
needs by following the instructions bellow.
1. Remove the air signal line from the actuator and
replace with a pressure gauge and an air regulator.
2. Loosen, but do not remove the Stem Connector
Bolt and Nut (30,31).
3. Adjust the actuator air pressure to just below the
starting point of the range and rotate the Actuator
Stem (14) until the stem just starts to move. Contin-
ue to rotate the Actuator Stem about one-half turn.
4. Remove the air pressure. Gradually increase the
air pressure and check at what pressure the valve
stem starts to move. Repeat Actuator Stem Adjust-
ment (step 3) if necessary and again check to see
if the stem starts to move at the desired pressure.
5. After the preload has been properly adjusted,
tighten the Stem Connector Bolt and Nut (30,31)
and reattach the control air signal line.