Data Sheet

Bulletin 71.4:LR128
2
Specications
Main Valve Body Sizes, End Connection Styles
and Structural Design Ratings
(1)(2)
See Table 1
Maximum Inlet Pressure
(1)
Type LR128 Main Valve: See Table 1
Type MR98H Pilot: See Table 2
Type 112 Restrictor: 1500 psig / 103 bar
Maximum Outlet Pressure
Type LR128 Main Valve: See Table 1
Type MR98H Pilot: 450 psig / 31.0 bar
Relief Set Pressure/Backpressure Control Ranges
See Table 3
Main Valve Plug Travel
1 in. / DN 25: 0.37 in. / 9.4 mm
2 in. / DN 50: 0.68 in. / 17 mm
3 in. / DN 80: 0.98 in. / 25 mm
4 in. / DN 100: 1.19 in. / 30 mm
Main Valve Minimum Differential Pressure
(1)
See Table 5
Main Valve Maximum Differential Pressure
(1)
See Table 6
Temperature Capabilities
(1)
See Table 10
Main Valve Flow Direction
Up through the center of the cage and down
through the cage slots
Main Valve Internal Inlet Strainer Sizes
1 in. / DN 25: 12 Mesh (0.0661 in. / 1.68 mm)
(3)
2, 3 and 4 in. / DN 50, 80 and 100:
10 Mesh (0.0787 in. / 2.00 mm)
(3)
Flow and IEC Sizing Coefcients
Type LR128 Main Valve: See Table 7
Type MR98H Pilot: See Table 8
Type 112 Restrictor: See Table 9
Flow Capacities
See Table 13
Pressure Registration
External: 1/8 NPT
Spring Case Vent
Type Y602-12
Approximate Weights
See Table 11
Options
 • Pre-pipedPilotSupply
• TravelIndicator
Construction Materials
Type LR128 Main Valve
Body: WCC Steel, CF8M or CF3M Stainless steel
Bonnet: LF2 Steel or 316/316L Stainless steel
Bonnet Bushing: 416 Hardened Stainless steel
Cage: 15-5 Stainless steel
Spring: 302 Stainless steel or 17-7 Stainless steel
Top Plug: 17-4 Stainless steel
Bottom Plug: 416 Stainless steel
Inlet Strainer: Stainless steel
Diaphragm: Nitrile (NBR) or Fluorocarbon (FKM)
O-Rings: Nitrile (NBR) or Fluorocarbon (FKM)
Flanged Locknut: 17-4 Stainless steel
Backup Rings:Polytetrauoroethylene(PTFE)
Upper Spring Seat: 416 Stainless steel
Indicator Protector and Cover: Plastic
Indicator Stem: 303 Stainless steel
Indicator Fitting: 416 Stainless steel
Travel Indicator Plug: 416 Stainless steel
Type MR98H Pilot
Body: WCC Steel or 316 Stainless steel
Spring Case: WCC Steel or 316 Stainless steel
Orice: 416 Stainless steel
Valve Plug: 416 Stainless Steel
Guide and Pusher Post: 416 Stainless steel
Gasket: Nitrile (NBR) or Fluorocarbon (FKM)
O-rings: Nitrile (NBR) or Fluorocarbon (FKM)
Diaphragm: Neoprene (CR) or
Fluorocarbon (FKM)
Mounting Parts
Pilot Mounting Pipe Nipple: Plated steel or
Stainless steel
Pipe Fittings: Plated steel or Stainless steel
Tubing: Stainless steel
Type 112 Restrictor
Body: 15-5 Stainless steel
Groove Valve: 416 Stainless steel
Retainer: 416 Stainless steel
Pipe Plug: 316 Stainless steel
O-rings: Nitrile (NBR) or Fluorocarbon (FKM)
1.Thepressure/temperaturelimitsinthisBulletinandanyapplicablestandardorcodelimitationshouldnotbeexceeded.
2.RatingsandendconnectionsotherthanASMEstandardscanusuallybeprovided;contactyourlocalSalesOfce.
3. Nominal sieve opening.