Swagelok LBS4 User manual

LBS4 Back-Pressure Regulator User Manual
Read the complete manual before installing and using the regulator.

2
Safe Product Selection
When selecting a product, the total system design must be considered to ensure safe, trouble-free
performance. Function, material compatibility, adequate ratings, proper installation, operation, and
maintenance are the responsibilities of the system designer and user.
WARNING
•Users must be trained and equipped for the handling, use, and servicing of pressure
products and systems.
•Users must contact their gas or liquid supplier for specific safety precautions and
instructions.
•Gaseous media should be free of excessive moisture to prevent icing at high flow.
•Always wear the appropriate protective clothing, including safety glasses, gloves, etc., if
required.
•Follow the applicable safety and maintenance procedures.
•Obey specific local regulations.
•Do not exceed the maximum inlet and outlet pressure rating of the product or its
accessories.
•Operate within the temperature limits and any other conditions specified for the product.
•Do not drop or damage the product in any other way. This may negatively affect the
performance of the product which can cause the product to malfunction.
•Venting fluids and gases can be dangerous. Vent to a safe environment away from people.
Ensure adequate ventilation.

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Contents
Introduction........................................................................................................................................................ 4
Overview.......................................................................................................................................................... 4
Standard Features........................................................................................................................................... 4
Additional Options ........................................................................................................................................... 4
Oxygen Service ............................................................................................................................................... 4
Installation.......................................................................................................................................................... 5
Points of Attention Before Installation ............................................................................................................. 5
Installation ....................................................................................................................................................... 5
Operation............................................................................................................................................................ 6
Required Tools for Operation.......................................................................................................................... 6
Points of Attention Before Operation............................................................................................................... 6
Adjusting the Set Pressure.............................................................................................................................. 6
Maintenance ....................................................................................................................................................... 7
Required Tools for Maintenance ..................................................................................................................... 7
Points of Attention Before Removal from the System..................................................................................... 8
Removal from the System ............................................................................................................................... 8
Assembly Reference Data............................................................................................................................... 9
Disassembly .................................................................................................................................................. 13
Points of Attention Before Reassembly......................................................................................................... 13
Reassembly................................................................................................................................................... 13
Testing .............................................................................................................................................................. 14
Seat Leak Test .............................................................................................................................................. 14
Shell Leak Test.............................................................................................................................................. 14
Troubleshooting .............................................................................................................................................. 15

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Introduction
Overview
- The LBS4 series are spring loaded back pressure regulators designed for high sensitivity regulation of
gases and liquids.
- For pressure and temperature rating information refer to the Pressure Regulators, RHPS Series catalog,
MS-02-430.
WARNING
Check that system pressures and temperatures do not exceed those stated on the regulator as
this could result in product failure.
Standard Features
- Bolted construction
- Stainless steel as standard
- Fully serviceable
- Diaphragm sensing
- Bottom mounting
- Panel mounting
Additional Options
The regulator is available with the following options:
Anti-tamper
Oxygen Service
- For more information about hazards and risks of oxygen enriched systems see the Swagelok Oxygen
System Safety technical report (MS-06-13).
- Cleaning and packaging to ensure compliance with product cleanliness requirements stated in ASTM G93
Level C is available. Refer to the Pressure Regulators, RHPS Series catalog, MS-02-430, for additional
information.

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Installation
CAUTION
Do not use the regulator as a shutoff device. A level of leakage across the regulator seat can
occur during normal operation.
Points of Attention Before Installation
This regulator can be equipped with a variety of different options and connections. Before installing the
regulator you should fully understand the functions of the supplied options and the suitability of your particular
regulator for the intended application.
- The preferred mounting position of the regulator is horizontal with the spring housing facing upwards per
Fig 2. Alternative mounting positions may increase the risk of component wear.
- It may be necessary to remove the regulator from the system during maintenance or service. Ensure that
this is possible.
- The regulator is suitable for gases and liquids. Ensure compatibility between the regulator’s materials of
construction and the system media.
Installation
- Verify that the regulator, its connections, and any accessories are undamaged.
- Verify that the regulator and any accessories are suitable for the system operating pressure and
temperature and have suitable connections.
- At the time of delivery any gauge ports may be plugged with blind fittings. Remove these and connect
gauges if desired.
- If inlet/outlet fittings are being used, assemble them to the regulator, per the manufacturer’s instructions,
prior to installing the regulator in the system.
CAUTION
Ensure all upstream tubing/pipework is clean and free from debris. Any swarf, lint, wire, etc. may
damage the regulator, resulting in a seat leak.
- Verify the flow direction of the system and mount the regulator accordingly.
- Securely make the appropriate connections to the regulator in accordance with the procedures
recommended by the connection manufacturer.
- Ensure that the tubing/pipework and the regulator are adequately supported and that there is no stress
on the connections.
- Upstream and downstream shutoff valves should be installed in the system to facilitate servicing,
maintenance, and troubleshooting of the regulator.

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Operation
Required Tools for Operation
- No tools are required for changing the set pressure on a standard regulator.
- A 20 mm open-ended wrench and a 13 mm open-ended wrench or socket are required for anti-tamper
regulators.
Points of Attention Before Operation
CAUTION
The product can be hot or cold, depending on the environmental temperature and the process
media temperature. Take the necessary precautions before operating or touching the product.
- Once the regulator closes, after being open to flow, the inlet pressure may fall a little under the set
pressure. This is usually referred to as “reseat pressure”. This phenomenon does not indicate a
problem with the regulator.
- An increase in the flow may result in a rise of the set pressure. A decrease in the flow may result in a fall
of the set pressure. This is usually referred to as “accumulation”.This phenomenon does not indicate a
problem with the regulator.
- An increase of the outlet pressure may result in a fall of the set pressure. A decrease of the outlet
pressure may result in a rise of the set pressure. This is usually referred to as “dependency”. This
phenomenon does not indicate a problem with the regulator.
Adjusting the Set Pressure
- The set pressure is the desired upstream pressure of the regulator.
- To set the regulator, ensure that the supply pressure is greater than the required set pressure but does
not exceed the maximum rating of the regulator.
- The regulator must be able to flow in order to adjust the set pressure.
1. Open any downstream valve.
2. To operate the regulator, turn the adjustment knob clockwise to increase the set pressure. Turn the knob
counterclockwise to reduce the set pressure.
3. Partially open the supply valve to allow the regulator to sense the inlet pressure with minimal flow.
4. Close the supply valve and verify the set pressure by measuring the regulator inlet pressure.
5. Make adjustments to the set pressure as required and repeat steps 3 and 4.
6. To obtain the most accurate set pressure, final adjustment must be made while increasing the set
pressure. If the desired set pressure is exceeded, reduce the pressure below this value then increase up
to it.
7. Once the regulator is set, the supply pressure can be adjusted to its normal working value.
8. Open the supply valve fully to allow full flow during operation.
9. When in operation make any final set pressure adjustments if required.
NOTICE
The LBS4 series knob assembly is retained by a C-ring. When backing off the knob do not
attempt to continue to unwind the knob once it has stopped. Doing so may damage the C-ring.

7
Maintenance
WARNING
Incorrect or improper repair or servicing of this product can cause serious personal injury and
property damage.
- All repairs, servicing, and testing of this product must be performed by competent personnel.
- Following any maintenance of the regulator, it is recommended that the product be tested for operation
and leakage.
- The product should be checked periodically for proper and safe operation. It is the user’s sole
responsibility to determine the frequency of maintenance based on the application.
- To reduce maintenance related system downtime to a minimum, either during commissioning or normal
operation, Swagelok recommends having maintenance kits readily available on site. The need for
maintenance kits is particularly important during the commissioning phase of a system installation due to
residual assembly debris remaining in the system. Such debris can cause a seat leak in the regulator,
resulting in components needing to be replaced.
Required Tools for Maintenance
Smooth-jawed vise
Seat retainer insertion tool:
RHPS-4-SEAT-TOOL
13 mm open-ended
wrench
Calibrated torque wrench up to
22 lbf·ft (30 N·m)
C-ring pliers
Lubricant (included in kit):
WL-8①
Krytox® 240 AC②
Adhesive (not included in kit):
Loctite® 5045, 4052 or 243
5 mm hex drive
Liquid leak detector
①Standard cleaned assemblies
②ASTM G93 or SC11 cleaned assemblies
Table 1

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Points of Attention Before Removal from the System
- Swagelok recommends removing the regulator from the system for servicing and maintenance.
- Follow all local system safety and maintenance procedures when removing the regulator.
WARNING
Before removing a regulator from the system, to avoid personal injury, you must:
•Depressurize the system.
•Purge the system to remove any residual system media left in the regulator.
•Always vent to a safe environment away from people and ensure there is adequate
ventilation.
CAUTION
Check if the process media is hazardous or toxic. If required, take the necessary safety
precautions to ensure a safe workspace and your personal safety.
CAUTION
The product can be hot or cold, depending on the environmental temperature and the process
media temperature. Take the necessary precautions before operating or touching the product.
Removal from the System
1. Isolate the regulator from all pressure sources by closing all appropriate upstream valves in the system.
2. With the regulator set to the open position (i.e. handle backed off fully counterclockwise) , open all
appropriate downstream valves to allow pressure to vent from the regulator.
WARNING
Ensure all pressure on the inlet and outlet has been fully vented. The accidental release of
residual trapped pressure can cause serious personal injury.
3. Disconnect and remove the regulator from the system.

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Assembly Reference Data
Item
Component Name
Kit Type(s)
Torque
lbf·ft (N·m)
Recommended Lubrication
(included in kit per Table 1)
1
Body
N/A
2
Seat
A1, B1, C1
3
Seat O-Ring
A1, B1, B2, C1
4
Seat retainer
C1
11 (15)
Lubricate threads
5
Poppet
A1, A2, B1, C1
7 (10)
Lubricate threads
6
Diaphragm
B1, B2, C1, C3
7
Bottom spring guide
C1
8
Stroke limiting ring①
C1
9
Clamp ring
C1
10
Set spring
C1, C4
11
Spring guide
C1
Lubricate central recess
12
Spring housing
N/A
13
Washer
E1
14
Cap screw
E1
9 (12)
Lubricate threads
15
C-ring
D1
16
Spring housing cover
N/A
22 (30)
Adhesive on external threads
17
Knob assembly
D1
Lubricate threads
18
Anti-tamper set
screw
D1
Lubricate threads
19
Lock nut
D1
20
Anti-tamper cover
D1
Lubricate threads
21
Blind plugs
N/A
15 (20)
Wrap threads in 2 layers of PTFE tape.
Lubricate tape.
①Metal diaphragm option only
Table 2
For more information on RHPS series maintenance kits, refer to the Pressure Regulators, RHPS Series
catalog, MS-02-430.

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LBS4 Series, Exploded View
Fig 1