PartsTable TECHNICAL DATA SHEET
JULY 2026Technical Data Sheet

1851Valve,safety Relief

Ashcroft Inc Dba Heise · NSN 4820-00-800-6156 · FSC 4820 · No Item Name Available
Verified by PartsTable
NSN 4820-00-800-6156 — this item is cataloged by the U.S. Government under National Stock Number 4820-00-800-6156. Primary manufacturer part number: 1851.
Features
  • Valve,safety Relief — FSC 4820
  • Material: COPPER ALLOY BODY
  • Nominal Pipe Size Accommodated: 0.500 INCHES SECOND END IN
  • Material: COPPER ALLOY SEAT
  • Thread Quantity Per Inch: 14 FIRST END
  • Thread Direction: RIGHT-HAND FIRST END
  • Connection Type: THREADED INTERNAL PIPE FIRST END
  • Thread Series Designator: NPT FIRST END
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 4820-00-800-6156, is classified within Federal Supply Class 4820 (No Item Name Available) of the Valves group. The primary manufacturer of record is Ashcroft Inc Dba Heise. Government technical data includes 30 verified specifications, sourced from the Federal Logistics Information System (FLIS). This item has 1 commercial cross-reference from 1 manufacturer, 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
NSN4820-00-800-6156
Primary Part Number1851
Item NameValve,safety Relief
FSC / FSG4820 / 48 — No Item Name Available
ManufacturerAshcroft Inc Dba Heise
StatusACTIVE
MaterialCOPPER ALLOY BODY
Nominal Pipe Size Accommodated0.500 INCHES SECOND END IN
MaterialCOPPER ALLOY SEAT
Thread Quantity Per Inch14 FIRST END
Thread DirectionRIGHT-HAND FIRST END
Connection TypeTHREADED INTERNAL PIPE FIRST END
Thread Series DesignatorNPT FIRST END
Nominal Pipe Size Accommodated0.750 INCHES FIRST END IN
Opening Pressure Setting10.0 POUNDS PER SQUARE INCH LBS
Features ProvidedVALVE STEM LOCK SHIELD AND BONNET PACKING AND PRESSURE TIGHT OUTLET SIDE
Bonnet Attachment MethodTHREADED
Operating Pressure300.0 POUNDS PER SQUARE INCH (PSI) MAXIMUM FIRST RESPONSE LBS
Operating Pressure300.0 POUNDS PER SQUARE INCH (PSI) MAXIMUM SECOND RESPONSE LBS
Valve Discharge Flow Rate15.0 CUBIC FEET PER MINUTE
Thread Quantity Per Inch14 SECOND END
Thread Series DesignatorNPT SECOND END
Nominal Thread Size0.500 INCHES SECOND END IN
Thread DirectionRIGHT-HAND SECOND END
Nominal Thread Size0.750 INCHES FIRST END IN
Maximum Operating Temp170.0 FAHRENHEIT SECOND RESPONSE DEGF
Connection TypeTHREADED EXTERNAL PIPE SECOND END
MaterialSTEEL STEM
Valve Operation MethodAUTOMATIC OR MANUAL
Bonnet TypeINSIDE SPRING
Flow Control DevicePOPPET
Maximum Operating Temp170.0 FAHRENHEIT FIRST RESPONSE DEGF
Reference Number Differentiating CharacteristicsAS DIFFERENTIATED BY VALVE SIZE ANDSET PRESSURE
Connection StylePLAIN (PIPE) SECOND END
Disk Loading MethodSPRING
Style DesignatorANGLE
Lifecycle & Compliance
Acquisition StatusACTIVE
HAZMATNo
Verified Substitutes 12
4820-00-036-1730005-500-0001 INTERCHANGEABLE
Disk,valve
Emerson Automation Solutions Final Control Us Lp Div Navy Product Team
3110-00-117-05711851 INTERCHANGEABLE
Bearing,ball,annular
Pierce Co Inc the Sub of Avis Industrial Corp
5325-00-148-55091851 INTERCHANGEABLE
Stud,lock Pin Fastener
Quincy Compressor Division of Coltec Industries Inc Dba Quincy Compressor Div Quincy Compressor
5960-00-188-3921 INTERCHANGEABLE
Electron Tube
3455-00-241-303817531 INTERCHANGEABLE
Cutter,milling,angle
Brown & Sharpe, Inc. Div Precision Measuring Instruments, Tesa Usa
1630-00-394-1598G185-1 INTERCHANGEABLE
Ring,wheel Flinger
Goodrich Corporation Div Collins Aerospace, Landing Systems (wheels & Brakes)
6150-00-424-60851851 INTERCHANGEABLE
Cable Assembly,special Purpose,e
Mission Systems Davenport Inc.
2520-00-495-709818-5-1 INTERCHANGEABLE
Gear
Dana Commercial Vehicle Manufacturing, Llc Dba Dana Commercial Vehicle Products
3020-00-540-44491851 INTERCHANGEABLE
Gear,spur
L3harris Technologies, Inc. Div Space and Airborne Systems
5120-00-640-6725185-1X INTERCHANGEABLE
Bit,screwdriver
Apex Tool Group, Llc
Cross-Reference Index
Part NumberManufacturer
1851 Ashcroft Inc Dba Heise (USA)
Related Parts
4820-00-036-1730INTERCHANGEABLE
DISK,VALVE
005-500-0001
3110-00-117-0571INTERCHANGEABLE
BEARING,BALL,ANNULAR
1851
5325-00-148-5509INTERCHANGEABLE
STUD,LOCK PIN FASTENER
1851
5960-00-188-3921INTERCHANGEABLE
ELECTRON TUBE
3455-00-241-3038INTERCHANGEABLE
CUTTER,MILLING,ANGLE
17531
1630-00-394-1598INTERCHANGEABLE
RING,WHEEL FLINGER
G185-1
6150-00-424-6085INTERCHANGEABLE
CABLE ASSEMBLY,SPECIAL PURPOSE,E
1851
2520-00-495-7098INTERCHANGEABLE
GEAR
18-5-1
3020-00-540-4449INTERCHANGEABLE
GEAR,SPUR
1851
5120-00-640-6725INTERCHANGEABLE
BIT,SCREWDRIVER
185-1X
4730-00-814-4581INTERCHANGEABLE
FITTING,LUBRICATION
1851
5999-00-986-7372INTERCHANGEABLE
DELAY LINE
712810-16REVA

Frequently Asked Questions

What is NSN 4820-00-800-6156?

NSN 4820-00-800-6156 is a Valve,safety Relief, manufactured by Ashcroft Inc Dba Heise, classified under FSC 4820 (No Item Name Available). Status: active.

What are the part numbers for NSN 4820-00-800-6156?

NSN 4820-00-800-6156 has 1 cross-referenced part number: 1851 (Ashcroft Inc Dba Heise).

What NSN replaces 4820-00-800-6156?

There are 12 known substitutes for 4820-00-800-6156: 4820-00-036-1730, 3110-00-117-0571, 5325-00-148-5509 and 9 more. Verify interchangeability with system specifications before substitution.

What are the specifications of 1851?

Key specifications for 1851: Material: COPPER ALLOY BODY; Nominal Pipe Size Accommodated: 0.500 INCHES SECOND END IN; Material: COPPER ALLOY SEAT; Thread Quantity Per Inch: 14 FIRST END. 30 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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