PartsTable TECHNICAL DATA SHEET
JULY 2026Technical Data Sheet

4255605Valve,safety Relief

The Boeing Company · NSN 4820-00-697-0994 · FSC 4820 · No Item Name Available
Verified by PartsTable
NSN 4820-00-697-0994 — this item is cataloged by the U.S. Government under National Stock Number 4820-00-697-0994. Primary manufacturer part number: 4255605.
Features
  • Valve,safety Relief — FSC 4820
  • Thread Quantity Per Inch: 18 FIRST END
  • Adjustable Pressure Range: +3000.0 TO 4500.0 POUNDS PER SQUARE INCH LBS
  • Disk Loading Method: SPRING
  • Material: STEEL CORROSION RESISTING SEAT
  • Connection Style: GASKET SEAL(BOSS) FIRST END
  • Thread Direction: RIGHT-HAND FIRST END
  • Material: STEEL CORROSION RESISTING STEM
Applications
  • Flow control in piping systems
  • Pressure regulation
  • Steam and fluid isolation
  • Applications requiring Steel Corrosion Resisting Seat construction
General Description

The Valve,safety Relief, cataloged under National Stock Number 4820-00-697-0994, is classified within Federal Supply Class 4820 (No Item Name Available) of the Valves group. The primary manufacturer of record is The Boeing Company. Government technical data includes 18 verified specifications, sourced from the Federal Logistics Information System (FLIS). This item has 6 commercial cross-references from 2 manufacturers, enabling identification through both NSN and commercial part number lookups. 12 verified substitutes exist in the FLIS interchangeability database. Current acquisition status: Cancelled.

Technical Specifications
ParameterValue
NSN4820-00-697-0994
Primary Part Number4255605
Item NameValve,safety Relief
FSC / FSG4820 / 48 — No Item Name Available
ManufacturerThe Boeing Company
StatusCANCELLED
Thread Quantity Per Inch18 FIRST END
Adjustable Pressure Range+3000.0 TO 4500.0 POUNDS PER SQUARE INCH LBS
Disk Loading MethodSPRING
MaterialSTEEL CORROSION RESISTING SEAT
Connection StyleGASKET SEAL(BOSS) FIRST END
Thread DirectionRIGHT-HAND FIRST END
MaterialSTEEL CORROSION RESISTING STEM
Nominal Outside Diameter Tube Accommodated0.375 INCHES FIRST END IN
Style DesignatorCROSS W/OFFSET
Nominal Thread Size0.562 INCHES FIRST END IN
Thread Series DesignatorUNF FIRST END
Operating Pressure3250.0 POUNDS PER SQUARE INCH (PSI) NOMINAL POWER DRIVE LBS
Thread Class3B FIRST END
MaterialALUMINUM ALLOY BODY
Valve Discharge Flow Rate0.7 GALLONS PER MINUTE
Connection TypeTHREADED INTERNAL BOSS FIRST END
Flow Control DevicePISTON
Valve Operation MethodAUTOMATIC
Lifecycle & Compliance
Acquisition StatusCANCELLED
HAZMATNo
Verified Substitutes 12
5330-00-161-968115048 INTERCHANGEABLE
Packing,preformed
Eaton Corporation Div Eaton Fluid Power
5133-00-189-9293 INTERCHANGEABLE
Drill,twist
5310-00-786-249715048 INTERCHANGEABLE
Washer,key
Williams International Co., L.l.c.
4010-00-840-38861504-8 INTERCHANGEABLE
Chain Assembly,single Leg
Avibank Mfg., Inc. Dba Avibank Manufacturing Inc
1660-00-942-877826089 INTERCHANGEABLE
Pin,locking,adapter
Avox Systems Inc Dba Avox Systems Inc
6520-01-003-212115048 INTERCHANGEABLE
Bur,dental,excavating
Ss White Burs Llc
5330-01-270-8334150-48-010 INTERCHANGEABLE
Gasket
Cone Drive Operations Inc
3040-01-289-359001-702-24 INTERCHANGEABLE
Clamp,hub
Secs Inc
5360-01-313-296415048 INTERCHANGEABLE
Spring,helical,compression
Forenta Lp
5110-01-335-15818MA INTERCHANGEABLE
File,hand
Idsc Holdings Llc Div Snap-on Industrial, a Div. of Idsc Holdings , Llc
Cross-Reference Index
Part NumberManufacturer
4255605 PRIMARY The Boeing Company (USA)
4263879-500 PRIMARY The Boeing Company (USA)
26089 PRIMARY Hydro-Aire Aerospace Corp (USA)
4255605 The Boeing Company (USA)
15048 Hydro-Aire Aerospace Corp (USA)
4263879-502 PRIMARY The Boeing Company (USA)
Related Parts
5330-00-161-9681INTERCHANGEABLE
PACKING,PREFORMED
15048
5133-00-189-9293INTERCHANGEABLE
DRILL,TWIST
5310-00-786-2497INTERCHANGEABLE
WASHER,KEY
15048
4010-00-840-3886INTERCHANGEABLE
CHAIN ASSEMBLY,SINGLE LEG
1504-8
1660-00-942-8778INTERCHANGEABLE
PIN,LOCKING,ADAPTER
26089
6520-01-003-2121INTERCHANGEABLE
BUR,DENTAL,EXCAVATING
15048
5330-01-270-8334INTERCHANGEABLE
GASKET
150-48-010
3040-01-289-3590INTERCHANGEABLE
CLAMP,HUB
01-702-24
5360-01-313-2964INTERCHANGEABLE
SPRING,HELICAL,COMPRESSION
15048
5110-01-335-1581INTERCHANGEABLE
FILE,HAND
8MA
6240-01-344-5055INTERCHANGEABLE
LAMP,INCANDESCENT
150/120R/FL/SS/120V
5331-01-387-0181INTERCHANGEABLE
O-RING
26089

Frequently Asked Questions

What is NSN 4820-00-697-0994?

NSN 4820-00-697-0994 is a Valve,safety Relief, manufactured by The Boeing Company, classified under FSC 4820 (No Item Name Available). Status: cancelled.

What are the part numbers for NSN 4820-00-697-0994?

NSN 4820-00-697-0994 has 6 cross-referenced part numbers: 4255605 (The Boeing Company), 4263879-500 (The Boeing Company), 26089 (Hydro-Aire Aerospace Corp), 4255605 (The Boeing Company), 15048 (Hydro-Aire Aerospace Corp) and 1 more.

What NSN replaces 4820-00-697-0994?

There are 12 known substitutes for 4820-00-697-0994: 5330-00-161-9681, 5133-00-189-9293, 5310-00-786-2497 and 9 more. Verify interchangeability with system specifications before substitution.

What are the specifications of 4255605?

Key specifications for 4255605: Thread Quantity Per Inch: 18 FIRST END; Adjustable Pressure Range: +3000.0 TO 4500.0 POUNDS PER SQUARE INCH LBS; Disk Loading Method: SPRING; Material: STEEL CORROSION RESISTING SEAT. 18 total characteristics are documented in the Federal Logistics Information System.

Is NSN 4820-00-697-0994 still in active supply?

NSN 4820-00-697-0994 is currently cancelled. Check with the Defense Logistics Agency for current availability and authorized substitutes.

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