PartsTable TECHNICAL DATA SHEET
JULY 2026Technical Data Sheet

146D525-1Valve,safety Relief

Telephonics Corp · NSN 4820-00-277-3853 · FSC 4820 · No Item Name Available
Verified by PartsTable
NSN 4820-00-277-3853 — this item is cataloged by the U.S. Government under National Stock Number 4820-00-277-3853. Primary manufacturer part number: 146D525-1.
Features
  • Valve,safety Relief — FSC 4820
  • Thread Direction: RIGHT-HAND FIRST END
  • Thread Class: 2B FIRST END
  • Thread Quantity Per Inch: 16 FIRST END
  • Features Provided: PRESSURE TIGHT OUTLET SIDE
  • Valve Discharge Flow Rate: 10.0 GALLONS PER MINUTE
  • Adjustable Pressure Range: +500.0 TO 4500.0 POUNDS PER SQUARE INCH LBS
  • Connection Style: GASKET SEAL(BOSS) FIRST END
Applications
  • Flow control in piping systems
  • Pressure regulation
  • Steam and fluid isolation
General Description

The Valve,safety Relief, cataloged under National Stock Number 4820-00-277-3853, is classified within Federal Supply Class 4820 (No Item Name Available) of the Valves group. The primary manufacturer of record is Telephonics Corp. Government technical data includes 15 verified specifications, sourced from the Federal Logistics Information System (FLIS). This item has 2 commercial cross-references from 2 manufacturers, enabling identification through both NSN and commercial part number lookups. 5 verified substitutes exist in the FLIS interchangeability database. Current acquisition status: Active.

Technical Specifications
ParameterValue
NSN4820-00-277-3853
Primary Part Number146D525-1
Item NameValve,safety Relief
FSC / FSG4820 / 48 — No Item Name Available
ManufacturerTelephonics Corp
StatusACTIVE
Thread DirectionRIGHT-HAND FIRST END
Thread Class2B FIRST END
Thread Quantity Per Inch16 FIRST END
Features ProvidedPRESSURE TIGHT OUTLET SIDE
Valve Discharge Flow Rate10.0 GALLONS PER MINUTE
Adjustable Pressure Range+500.0 TO 4500.0 POUNDS PER SQUARE INCH LBS
Connection StyleGASKET SEAL(BOSS) FIRST END
Renewable Seat Ring TypeTHREADED
Flow Control DevicePLUG
Nominal Thread Size0.750 INCHES FIRST END IN
Thread Series DesignatorUNF FIRST END
Operating Pressure3000.0 POUNDS PER SQUARE INCH (PSI) MAXIMUM SINGLE RESPONSE LBS
Valve Operation MethodAUTOMATIC
Connection TypeTHREADED INTERNAL BOSS FIRST END
Disk Loading MethodSPRING
Lifecycle & Compliance
Acquisition StatusACTIVE
HAZMATNo
Verified Substitutes 5
5133-00-262-2178 INTERCHANGEABLE
Drill,twist
5950-00-627-12321681818 INTERCHANGEABLE
Reactor
Navair and Navsea Managed Original Design Activity Dwg Not Material/parts Supplier
3110-01-030-7545 INTERCHANGEABLE
Ball,bearing
6515-01-580-352225-145 INTERCHANGEABLE
Power Supply,ventilator
Combat Medical Systems Llc
5935-01-612-780315067 INTERCHANGEABLE
Adapter,connector
Carrio Cabling Corporation
Cross-Reference Index
Part NumberManufacturer
1506-7 Droitcour Co (USA)
146D525-1 PRIMARY Telephonics Corp (USA)
Related Parts
5133-00-262-2178INTERCHANGEABLE
DRILL,TWIST
5950-00-627-1232INTERCHANGEABLE
REACTOR
1681818
3110-01-030-7545INTERCHANGEABLE
BALL,BEARING
6515-01-580-3522INTERCHANGEABLE
POWER SUPPLY,VENTILATOR
25-145
5935-01-612-7803INTERCHANGEABLE
ADAPTER,CONNECTOR
15067

Frequently Asked Questions

What is NSN 4820-00-277-3853?

NSN 4820-00-277-3853 is a Valve,safety Relief, manufactured by Telephonics Corp, classified under FSC 4820 (No Item Name Available). Status: active.

What are the part numbers for NSN 4820-00-277-3853?

NSN 4820-00-277-3853 has 2 cross-referenced part numbers: 1506-7 (Droitcour Co), 146D525-1 (Telephonics Corp).

What NSN replaces 4820-00-277-3853?

There are 5 known substitutes for 4820-00-277-3853: 5133-00-262-2178, 5950-00-627-1232, 3110-01-030-7545 and 2 more. Verify interchangeability with system specifications before substitution.

What are the specifications of 146D525-1?

Key specifications for 146D525-1: Thread Direction: RIGHT-HAND FIRST END; Thread Class: 2B FIRST END; Thread Quantity Per Inch: 16 FIRST END; Features Provided: PRESSURE TIGHT OUTLET SIDE. 15 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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