Swagelok RHPS Series User manual

RHPS Series
RD(H)F40
User Manual
Read the complete manual before installing and using the regulator.

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Contents
Introduction ............................................................................................................................................ 3
Installation .............................................................................................................................................. 4
Operation ................................................................................................................................................ 7
Maintenance ........................................................................................................................................... 8
Testing .................................................................................................................................................... 9
Troubleshooting ..................................................................................................................................... 9
WARNING
Before removing a regulator from the system for service, you must
▪depressurize system
▪purge the system to remove any residual system media left in the regulator.

Introduction
Representative drawing of the standard RD(H)F40
1 body 11 valve spring 22 ring 34 dynamic regulation tube
2 dome 13 guide ring 23 socket head cap screw 35 male connector
3 bottomplate 14 retaining ring 24 ring 36 tube 3/8”
4 valve case 15 ring 25 socket head cap screw 37 pilot regulator
5 valve case ring 16 socket head cap screw 27 tube 38 o-ring
6 valve stem 17 valve insert 28 flange 39 blindplug 1/4" bsp
7 bodyplate 18 diaphragm 30 bonded seal
8 domeplate 19 o-ring 31 male connector
9 diaphragmplate 20 o-ring 32 tube 3/8”
10 seat 21 o-ring 33 bleedplug 1/4" bsp

Installation
WARNING
When installing a Swagelok®self-venting regulator, position the vent connection or
line away from operating personnel. Operating personnel must protect themselves
from exposure to system fluids.
CAUTION
Do not use the regulators as a shutoff device.
CAUTION
When using the RDHF40 with an inlet pressure higher than 200 bar (2 902 psig), a
safety valve must be installed in the outlet line, because the outlet pressure may not
exceed 200 bar (2 902 psig).
Connections to System
The preferred mounting position of the regulator is horizontal with the dome facing upwards.
If grounding is required, connect a ground wire under a spring housing bolt.
Filling the dome
The dome can be filled using manual or electronic loading.
Manual loading:
1. This can be done by taking the gas pressure from the system and feeding this through a spring
loaded pilot regulator into the dome. This is shown in sketch A.
2. In liquid systems the gas pressure for manual dome loading can be taken from a cylinder or
mains. This is shown in sketch B.
Substituting the spring loaded pilot regulator for a proportional control valve and a pressure sensor,
allows you to control the pressure electronically.
Electronic loading:
1. This can be done by taking the gas pressure from the system and feeding this through a
proportional control valve into the dome. This is shown in sketch C.
This method can be used for low and medium pressure systems.
2. This can be done by taking the gas pressure from the system and feeding this through a
proportional controlled ratio regulator into the dome. This is shown in sketch D.
This method can be used for high pressure systems.

The best results will be achieved by allowing a small flow to continuously pass through the pilot
regulator.
This flow can either be vented or, in gas systems, fed back through an orifice into the downstream
piping.
This is usually referred to as “dynamic regulation”.
CAUTION
It is not recommended to place a gauge on the dome to set or check the outlet
pressure. Because of forces in the regulator, the dome pressure will always be higher
than the outlet pressure. Place a gauge in the outlet line to set or check the outlet
pressure.

External feedback
CAUTION
When using the regulator with external feedback, option –EF, make sure that the
outlet pressure can be fed back to the external feedback connection before applying
pressure to the regulator. Failing to do so may lead to damage and non-functioning of
the regulator as the inlet pressure will be put straight through to the outlet.
The purpose of the external feedback on a pressure regulator is to get a more accurate regulation of
the outlet pressure. This can be achieved by sensing the outlet pressure downstream of the regulator
and feeding it back to the regulator. For this purpose Swagelok has provided a special connection,
marked on the regulator itself as "P2 feedback".
Connecting the external feedback
The external feedback must be installed as follows:
▪The external feedback is to be connected in a turbulence-free zone in the downstream piping, at
a maximum distance of 5x the outside diameter of the down stream piping.
▪The external feedback must be connected on top of the downstream piping.
▪The tube-size of the external feedback should be ⅜in. or ½ in..
CAUTION
Never connect the external feedback line downstream of a shut-off valve.
Principle sketch of external feedback:

Operation
Note: All handle directions are when viewed from above.
▪Inlet and set pressure settings are obtained by adjusting pressure in the dome.
▪Increase the pressure in the dome to increase the inlet pressure.
▪Decrease the pressure in the dome to decrease the inlet pressure.
▪Icing of the regulator at high flow rates or high pressure drops may occur if the gaseous media or
atmosphere contains moisture.
▪An auxiliary upstream filter is recommended for use in all but the cleanest of media.
▪Installation of a downstream pressure relief is recommended for regulator and system protection.
▪If the shut-off valve at the outlet side is closed after changing the set pressure, the outlet pressure
will rise a little because of the closing force required for bubble-tight closing of the regulator.
▪This phenomenon is usually referred to as the “lock-up” and does not indicate a problem
with the regulator.
▪A decrease in the flow will result in a rise of the outlet pressure.
▪An increase in the flow will result in a fall of the outlet pressure and is usually referred to as
the “droop”.
▪This phenomenon does not indicate a problem with the regulator.
▪A decrease of the inlet pressure will result in a rise of the outlet pressure.
▪An increase of the inlet pressure will result in a fall of the outlet pressure.
▪This phenomenon is usually referred to as the “dependency” or “supply pressure effect” and
does not indicate a problem with the regulator.
CAUTION
If the pilot regulator also has changing inlet pressures, this will make the pressure
difference in the outlet line of the dome regulator even bigger. This is because the
pilot regulator will also increase it’s outlet pressure, which is the dome pressure.
Any rise to the dome pressure will result in a rise of the outlet pressure.
CAUTION
When using the RD(H)F40 with an inlet pressure higher than 200 bar (2 902 psig), a
safety valve must be installed in the outlet line, because the outlet pressure may not
exceed 200 bar (2 902 psig).

Maintenance
Required tools for maintenance
▪a vice to fasten the regulator
▪pincers to take out the o-rings
▪a pair of tongs for a retaining ring 140 mm
▪a torque wrench
▪a torque wrench hexagon head key 10 and 14
▪media and temperature compatible lubricant for reassembling threaded parts
▪media and temperature compatible lubricant for o-rings
▪Snoop®liquid leak detector
Disassembly
▪Loosen the hexagon socket head screws and remove the dome, dome plate, diaphragm and
diaphragm plate.
▪Loosen the hexagon socket head screws and remove the bottom plate, valve, valve spring and
seat.
Inspection of disassembled parts
▪Check all parts for abnormal wear. Replace parts in case of doubt.
Points of attention before assembly
- All parts must be clean and undamaged before starting assembly.
- Swagelok recommends replacing all o-rings and the diaphragm before assembly.
- All threaded parts must be lightly lubricated before assembly to avoid galling of threads.
- All o-rings need to be lightly lubricated to improve the lifetime of the o-ring and the
performance of the regulator.
Assembly
Follow the points for disassembly in reverse order to assemble the regulator.
Recommended torques
CAUTION
Only tighten the bolts or parts if the regulator is completely depressurized.
▪Hexagon socket head screws M12 50 N·m (442 in.·lb)
▪Hexagon socket head screws M16 90 N·m (796 in.·lb)

Testing
Check the regulator for leakage across the seat, with low- and high inlet pressure.
Check the regulator for leakage across the diaphragm, with low- and high outlet pressure.
A well performing RD(H)F40 is 100 % bubble tight.
If there is a leakage across the seat or the diaphragm, the damaged parts must be replaced.
Troubleshooting
Problem: The outlet pressure creeps up, without increasing the dome pressure.
Cause: A damaged valve and/or seat.
Solution: Replace the valve and/or the seat.
Problem: Leakage around the bottom plate.
Cause: A damaged o-ring or insufficient torque on the body plug.
Solution: Replace the o-ring or tighten the bolts according to the torque specifications.
Problem: Leakage between the body and the dome.
Cause: A damaged diaphragm or insufficient torque on the bolts.
Solution: Replace the diaphragm or tighten the bolts according to the torque specifications.
Problem: Controlled pressure drops off sharply even when the flow is within regulator capabilities.
Cause: The systems filter element is clogged.
Solution: Replace the system filter element.
Problem: The required set pressure can not be reached.
Cause: The inlet pressure to the dome regulator or to the pilot regulator is not high enough.
Solution: Make sure that the inlet pressure to the dome regulator and to the pilot regulator is sufficient.
Problem: The outlet pressure rises too much when going from a dynamic to a static situation.
Cause: There is too much flow in the dynamic situation.
Solution: A larger regulator is required.
Check the specific application data with the flow curves in our product literature, if available.
Problem: The outlet pressure does not drop if the pressure in the dome is lowered.
Cause: The valve is sticking.
Solution: Replace the valve assembly.
Problem: The outlet pressure has changed without adjusting the dome pressure.
Cause: Changes to the inlet pressure will result in changes to the outlet pressure.
Solution: Maintain a constant inlet pressure to the regulator. See section “operation” about dependency.

Warranty Information
Swagelok products are backed by The Swagelok Limited Lifetime Warranty.
For a copy, visit swagelok.com or contact your authorized Swagelok representative.
For additional information, see www.swagelok.com.
Swagelok, Snoop – Swagelok Company
© 2010 Swagelok Company
December 2010, R0
MS-CRD-0184
Caution: Do not mix or interchange parts
with those of other manufacturers.