PartsTable TECHNICAL DATA SHEET
JULY 2026Technical Data Sheet

20285R51MValve,safety Relief

Emerson Automation Solutions Final Control Us Lp Div Navy Product Team · NSN 4820-01-134-2803 · FSC 4820 · No Item Name Available
Verified by PartsTable
NSN 4820-01-134-2803 — this item is cataloged by the U.S. Government under National Stock Number 4820-01-134-2803. Primary manufacturer part number: 20285R51M.
Features
  • Valve,safety Relief — FSC 4820
  • Operating Pressure: 150.0 POUNDS PER SQUARE INCH (PSI) MAXIMUM SINGLE RESPONSE LBS
  • Material Document and Classification: QQ-C-390,ALLOY D4/D/ FED SPEC SINGLE MATERIAL RESPONSE BODY
  • Flange Face Design: PLAIN FIRST END
  • Nominal Outside Diameter: 3.875 INCHES FIRST END IN
  • Style Designator: ANGLE
  • Material Document and Classification: QQ-N-281 FED SPEC SINGLE MATERIAL RESPONSE SEAT
  • Material: COPPER ALLOY BODY
Applications
  • Flow control in piping systems
  • Pressure regulation
  • Steam and fluid isolation
  • Applications requiring Copper Alloy Body construction
General Description

The Valve,safety Relief, cataloged under National Stock Number 4820-01-134-2803, is classified within Federal Supply Class 4820 (No Item Name Available) of the Valves group. The primary manufacturer of record is Emerson Automation Solutions Final Control Us Lp Div Navy Product Team. Government technical data includes 26 verified specifications, sourced from the Federal Logistics Information System (FLIS). This item has 5 commercial cross-references from 3 manufacturers, enabling identification through both NSN and commercial part number lookups. 12 verified substitutes exist in the FLIS interchangeability database. Current acquisition status: Active.

Technical Specifications
ParameterValue
NSN4820-01-134-2803
Primary Part Number20285R51M
Item NameValve,safety Relief
FSC / FSG4820 / 48 — No Item Name Available
ManufacturerEmerson Automation Solutions Final Control Us Lp Div Navy Product Team
StatusACTIVE
Operating Pressure150.0 POUNDS PER SQUARE INCH (PSI) MAXIMUM SINGLE RESPONSE LBS
Material Document and ClassificationQQ-C-390,ALLOY D4/D/ FED SPEC SINGLE MATERIAL RESPONSE BODY
Flange Face DesignPLAIN FIRST END
Nominal Outside Diameter3.875 INCHES FIRST END IN
Style DesignatorANGLE
Material Document and ClassificationQQ-N-281 FED SPEC SINGLE MATERIAL RESPONSE SEAT
MaterialCOPPER ALLOY BODY
Connection TypeFLANGE FIRST END
Bonnet Attachment MethodBOLTED
MaterialNICKEL ALLOY SEAT
Flange ShapeROUND FIRST END
Media for Which DesignedAIR FIRST RESPONSE
Connection TypeUNTHREADED INTERNAL TUBE SECOND END
Connection StyleSTREAMLINED WITH ONE BRAZING RING (TUBE) SECOND END
MaterialNICKEL ALLOY FLOW CONTROL DEVICE
Valve Operation MethodAUTOMATIC
Adjustable Pressure Range+151.0 TO 180.0 POUNDS PER SQUARE INCH LBS
Maximum Operating Temp150.0 FAHRENHEIT SINGLE RESPONSE DEGF
Bonnet TypeINSIDE SPRING
MaterialNICKEL ALLOY STEM
Nominal Outside Diameter Tube Accommodated0.750 INCHES SECOND END IN
Media for Which DesignedGAS, INERT SECOND RESPONSE
Material Document and ClassificationQQ-N-281 FED SPEC SINGLE MATERIAL RESPONSE STEM
Material Document and ClassificationQQ-N-281 FED SPEC SINGLE MATERIAL RESPONSE FLOW CONTROL DEVICE
Flow Control DeviceDISK
Nominal Thickness0.344 INCHES FIRST END IN
Lifecycle & Compliance
Acquisition StatusACTIVE
HAZMATNo
Verified Substitutes 12
5841-00-338-1763359D133 INTERCHANGEABLE
Magnet Assy,focusin
General Dynamics Mission Systems, Inc. Dba Gdms
5950-00-647-5260 INTERCHANGEABLE
Transformer,power
4820-01-150-382107521004132 INTERCHANGEABLE
Pressure Screw,valve
Emerson Automation Solutions Final Control Us Lp Div Navy Product Team
5331-01-273-153820285 INTERCHANGEABLE
O-Ring
Bourns Inc
1650-01-395-73811-1327-1-6338 INTERCHANGEABLE
Disk,valve
Fluid Mechanics Valve Company
4820-01-396-193438202-3112S19 INTERCHANGEABLE
Valve,safety Relief
Fluid Mechanics Valve Company
6545-01-416-6000 INTERCHANGEABLE
Kit,ventilator,volu
6240-01-419-7793 INTERCHANGEABLE
Lamp,fluorescent
8145-01-580-751112573801 INTERCHANGEABLE
Shipping and Storage Container,e
U S Army Tank Automotive Command Amsta-Im-Mm
6680-01-651-780220285-0501 INTERCHANGEABLE
Transmitter,liquid Quantity
Simmonds Precision Products Inc
Cross-Reference Index
Part NumberManufacturer
20285R51M PRIMARY Emerson Automation Solutions Final Control Us Lp Div Navy Product Team (USA)
20285 PRIMARY Emerson Automation Solutions Final Control Us Lp Div Navy Product Team (USA)
20285 Anderson Greenwood Lp Dba Anderson Greenwood Crosby (USA)
10347159 Nimikkeistokeskus Ncb Finland (FIN)
20285R51M Anderson Greenwood Lp Dba Anderson Greenwood Crosby (USA)
Related Parts
5841-00-338-1763INTERCHANGEABLE
MAGNET ASSY,FOCUSIN
359D133
5950-00-647-5260INTERCHANGEABLE
TRANSFORMER,POWER
4820-01-150-3821INTERCHANGEABLE
PRESSURE SCREW,VALVE
07521004132
5331-01-273-1538INTERCHANGEABLE
O-RING
20285
1650-01-395-7381INTERCHANGEABLE
DISK,VALVE
1-1327-1-6338
4820-01-396-1934INTERCHANGEABLE
VALVE,SAFETY RELIEF
38202-3112S19
6545-01-416-6000INTERCHANGEABLE
KIT,VENTILATOR,VOLU
6240-01-419-7793INTERCHANGEABLE
LAMP,FLUORESCENT
8145-01-580-7511INTERCHANGEABLE
SHIPPING AND STORAGE CONTAINER,E
12573801
6680-01-651-7802INTERCHANGEABLE
TRANSMITTER,LIQUID QUANTITY
20285-0501
6680-01-652-1612INTERCHANGEABLE
TRANSMITTER,LIQUID QUANTITY
20285-0301
4320-01-657-8174INTERCHANGEABLE
SLEEVE,SHAFT,PUMP
20-285

Frequently Asked Questions

What is NSN 4820-01-134-2803?

NSN 4820-01-134-2803 is a Valve,safety Relief, manufactured by Emerson Automation Solutions Final Control Us Lp Div Navy Product Team, classified under FSC 4820 (No Item Name Available). Status: active.

What are the part numbers for NSN 4820-01-134-2803?

NSN 4820-01-134-2803 has 5 cross-referenced part numbers: 20285R51M (Emerson Automation Solutions Final Control Us Lp Div Navy Product Team), 20285 (Emerson Automation Solutions Final Control Us Lp Div Navy Product Team), 20285 (Anderson Greenwood Lp Dba Anderson Greenwood Crosby), 10347159 (Nimikkeistokeskus Ncb Finland), 20285R51M (Anderson Greenwood Lp Dba Anderson Greenwood Crosby).

What NSN replaces 4820-01-134-2803?

There are 12 known substitutes for 4820-01-134-2803: 5841-00-338-1763, 5950-00-647-5260, 4820-01-150-3821 and 9 more. Verify interchangeability with system specifications before substitution.

What are the specifications of 20285R51M?

Key specifications for 20285R51M: Operating Pressure: 150.0 POUNDS PER SQUARE INCH (PSI) MAXIMUM SINGLE RESPONSE LBS; Material Document and Classification: QQ-C-390,ALLOY D4/D/ FED SPEC SINGLE MATERIAL RESPONSE BODY; Flange Face Design: PLAIN FIRST END; Nominal Outside Diameter: 3.875 INCHES FIRST END IN. 27 total characteristics are documented in the Federal Logistics Information System.

Validated with multiple authoritative sources, including Government, OEM, and Certified sources.
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