APPLICATION
The 627 Series direct-operated pressure reducing regulators are for high and low pressure systems. These regulators can be used with natural gas, air, or a variety of other gases.
Direct-operated pressure reducing regulator equipped with a pilot tube for greater regulated capacities.
Materials
Body............................................................................... Aluminum
Bonnet ............................................................................Aluminum
Springs ............................................................................Steel
Valve Seat Discs ...........................................High Temperature Resilient Composition
Diaphragms ....................... ............................................Synthetic Rubber
Model
Model | Inch. | Max.inlet pressure (bar) | Normal use inlet Pressure (bar) | Outlet pressure (bar) |
WF627-15 | RP 1/2 " | 16 | 3-8 | 0.5-3 |
WF627-20 | RP 3/4 " | 16 | 3-8 | 0.5-3 |
WF627-25 | RP 1" | 16 | 3-8 | 0.5-3 |
WF627-50 | RP 2" | 16 | 3-8 | 0.5-3 |
Operational Schematic
Principle of Operation
When downstream demand decreases, the pressure under the diaphragm increases. This pressure overcomes the regulator setting (which is set by a spring). Through the action of the pusher post assembly, lever, and valve stem the valve disk moves closer to the orifice and reduces gas flow. If demand downstream increases, pressure under the diaphragm decreases. Spring force pushes the pusher post assembly downward and the valve disk moves away from the orifice.
Regulator Assembly
L1 = Multi-purpose lithium polymer type grease
L2 = extreme low-temperature bearing grease
Parts List
Part No. | Description | Part No. | Description | Part No. | Description |
1 | Body | 12 | Stem Back-up Ring | 31 | Lower Spring Seat |
2 | Orifice | 13 | Hair Pin Clip | 32 | Control Spring |
4 | Diaphragm Case O-ring | 14 | Drive Pin | 33 | Upper Spring Seat, |
5 | Diaphragm Case | 15 | Lever | 34 | Lock nut |
6 | Boost Body | 16 | Lever Retainer | 35 | Adjusting Screw |
7 | Stabilizer | 17 | Lever Pin | 36 | Adjusting Screw Cap |
8 | Stem Guide | 18 | Lever Cap Screw | 37 | Spring case cap screw |
9 | Disk Assembly | 19 | Pusher Post | 46 | Diaphragm head cap screw |
10 | Stem | 23 | Diaphragm |
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11 | Stem O-ring | 24 | Diaphragm Head |
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Installation notice
Regulator operation within ratings does not preclude the possibility of damage from debris in the lines or from external sources. A regulator should be inspected for damage periodically and after any over-pressure condition. Key numbers referenced in this section are shown in above .
Ensure that the operating temperature capabilities listed in Specifications section are not exceeded.
1. Only personnel qualified through training and experience should install, operate, or maintain this regulator.
2. For a regulator that is shipped separately, make sure that there is no damage to or foreign material in the regulator.
3. Ensure that all tubing and piping have been blown free of foreign debris.
4. The regulator may be installed in any position as long as the flow through the body is in the direction indicated by the arrow cast on the body.
5. If continuous operation is required during inspection or maintenance, install a three-valve bypass around the regulator.
Adjustment
The range of allowable pressure settings is marked on the nameplate. If a pressure setting beyond this range is necessary, substitute the appropriate regulator control spring. Change the nameplate to indicate the new pressure range.
Refer to above for key number locations.
1. Remove the adjusting screw cap (part.36).
2. Loosen the lock nut (part.34).
3. Increase the outlet pressure setting by turning the adjusting screw (part.35) clockwise. Decrease the outlet pressure setting by turning the adjusting screw counterclockwise.
4. When the desired pressure is obtained, hold the adjusting screw (part.35) in place and tighten the lock nut (part.34).
WARNING
A regulator may vent some gas to the atmosphere. In hazardous or flammable gas service, vented gas may accumulate and cause personal injury, death, or property damage due to fire or explosion. Vent a regulator in hazardous gas service to a remote, safe location away from air intakes or any hazardous area. The vent line or stack opening must be protected against condensation or clogging.
Start up
To avoid personal injury or property damage due to explosion or damage to regulator or downstream components during start-up, release downstream-pressure to prevent an over-pressure condition on the diaphragm of the regulator.In order to avoid an over-pressure condition and possible equipment damage, pressure gauges should always be used to monitor pressures during start up.
1. Slowly open the upstream shut-off valve.
2. Slowly open the downstream shut-off valve.
3. Check all connections for leaks.
4. Make final control spring adjustments according to the adjustment procedures.
Shutdown
To avoid personal injury or property damage due to explosion or damage to regulator or downstream components during shutdown, release downstream pressure to prevent an over-pressure condition on the diaphragm of the regulator.
1. Close the nearest upstream shut-off valve.
2. Close the nearest downstream shut-off valve.
3. Open the vent valve between the regulator and the downstream shut-off valve nearest to it.
4. For a Type 627 regulator, the regulator will open to release pressure between the upstream shut-off valve and the regulator.
