PartsTable TECHNICAL DATA SHEET
JULY 2026Technical Data Sheet

MILU18250Union,pipe

Military Specifications Promulgated by Military Departments/agencies Under Authority of Defense Standardization Manual 4120 3-M · NSN 4730-00-189-2630 · FSC 4730 · No Item Name Available
Verified by PartsTable
NSN 4730-00-189-2630 — this item is cataloged by the U.S. Government under National Stock Number 4730-00-189-2630. Primary manufacturer part number: MILU18250.
Features
  • Union,pipe — FSC 4730
  • Surface Treatment: ZINC OVERALL
  • Nominal Thread Size: 0.500 INCHES FIRST END IN
  • Thread Series Designator: NPT ALL ENDS
  • Material: STEEL OVERALL
  • Operating Pressure: 300.0 POUNDS PER SQUARE INCH (PSI) MAXIMUM SINGLE RESPONSE LBS
  • Specification/standard Data: 81349-MIL-U-18250 GOVERNMENT SPECIFICATION
  • Surface Treatment: ZINC OVERALL
Applications
  • Fluid conveyance
  • Hydraulic system plumbing
  • Pneumatic line routing
  • Applications requiring Steel Overall construction
General Description

The Union,pipe, cataloged under National Stock Number 4730-00-189-2630, is classified within Federal Supply Class 4730 (No Item Name Available) of the Pipe, Tubing, Hose, and Fittings group. The primary manufacturer of record is Military Specifications Promulgated by Military Departments/agencies Under Authority of Defense Standardization Manual 4120 3-M. Government technical data includes 24 verified specifications, sourced from the Federal Logistics Information System (FLIS). This item has 3 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: Active.

Technical Specifications
ParameterValue
NSN4730-00-189-2630
Primary Part NumberMILU18250
Item NameUnion,pipe
FSC / FSG4730 / 47 — No Item Name Available
ManufacturerMilitary Specifications Promulgated by Military Departments/agencies Under Authority of Defense Standardization Manual 4120 3-M
StatusACTIVE
Surface TreatmentZINC OVERALL
Nominal Thread Size0.500 INCHES FIRST END IN
Thread Series DesignatorNPT ALL ENDS
MaterialSTEEL OVERALL
Operating Pressure300.0 POUNDS PER SQUARE INCH (PSI) MAXIMUM SINGLE RESPONSE LBS
Specification/standard Data81349-MIL-U-18250 GOVERNMENT SPECIFICATION
Surface TreatmentZINC OVERALL
Seat TypeGROUND-JOINT
Nondefinitive Spec/std DataXB TYPE
Specification/standard Data81349-MIL-U-18250 GOVERNMENT SPECIFICATION
Nominal Overall Length1.930 INCHES IN
Nominal Thread Size0.500 INCHES FIRST END IN
Style DesignatorTHREADED
Connection StylePLAIN (PIPE) ALL ENDS
Style DesignatorTHREADED
Connection TypeTHREADED INTERNAL PIPE ALL ENDS
MaterialSTEEL OVERALL
Thread Series DesignatorNPT ALL ENDS
Media for Which DesignedSTEAM SINGLE RESPONSE
Seat TypeGROUND-JOINT
Nondefinitive Spec/std DataXB TYPE
Nominal Overall Length1.930 INCHES IN
Operating Pressure300.0 POUNDS PER SQUARE INCH (PSI) MAXIMUM SINGLE RESPONSE LBS
Media for Which DesignedSTEAM SINGLE RESPONSE
Lifecycle & Compliance
Acquisition StatusACTIVE
HAZMATNo
Verified Substitutes 12
4730-00-189-2598 INTERCHANGEABLE
Union,pipe
4730-00-189-2599 INTERCHANGEABLE
Union,pipe
4730-00-189-2600 INTERCHANGEABLE
Union,pipe
4730-00-189-26021631-400 INTERCHANGEABLE
Union,pipe
Flaton Machine Works Inc.
4730-00-189-2605 INTERCHANGEABLE
Union,pipe
4730-00-189-2606 INTERCHANGEABLE
Union,pipe
4730-00-189-2629 INTERCHANGEABLE
Union,pipe
4730-00-189-2635 INTERCHANGEABLE
Union,pipe
4730-00-189-2638 INTERCHANGEABLE
Union,pipe
4730-00-189-2639 INTERCHANGEABLE
Union,pipe
Cross-Reference Index
Part NumberManufacturer
MILU18250 Military Specifications Promulgated by Military Departments/agencies Under Authority of Defense Standardization Manual 4120 3-M
ASME B16.39 The American Society of Mechanical Engineers (USA)
ASME B16.39 CLASS 300 NPS 1/2 The American Society of Mechanical Engineers (USA)
Related Parts
4730-00-189-2598INTERCHANGEABLE
UNION,PIPE
4730-00-189-2599INTERCHANGEABLE
UNION,PIPE
4730-00-189-2600INTERCHANGEABLE
UNION,PIPE
4730-00-189-2602INTERCHANGEABLE
UNION,PIPE
1631-400
4730-00-189-2605INTERCHANGEABLE
UNION,PIPE
4730-00-189-2606INTERCHANGEABLE
UNION,PIPE
4730-00-189-2629INTERCHANGEABLE
UNION,PIPE
4730-00-189-2635INTERCHANGEABLE
UNION,PIPE
4730-00-189-2638INTERCHANGEABLE
UNION,PIPE
4730-00-189-2639INTERCHANGEABLE
UNION,PIPE
4730-00-189-2645INTERCHANGEABLE
UNION,PIPE
4730-00-189-2646INTERCHANGEABLE
UNION,PIPE

Frequently Asked Questions

What is NSN 4730-00-189-2630?

NSN 4730-00-189-2630 is a Union,pipe, manufactured by Military Specifications Promulgated by Military Departments/agencies Under Authority of Defense Standardization Manual 4120 3-M, classified under FSC 4730 (No Item Name Available). Status: active.

What are the part numbers for NSN 4730-00-189-2630?

NSN 4730-00-189-2630 has 3 cross-referenced part numbers: MILU18250 (Military Specifications Promulgated by Military Departments/agencies Under Authority of Defense Standardization Manual 4120 3-M), ASME B16.39 (The American Society of Mechanical Engineers), ASME B16.39 CLASS 300 NPS 1/2 (The American Society of Mechanical Engineers).

What NSN replaces 4730-00-189-2630?

There are 12 known substitutes for 4730-00-189-2630: 4730-00-189-2598, 4730-00-189-2599, 4730-00-189-2600 and 9 more. Verify interchangeability with system specifications before substitution.

What are the specifications of MILU18250?

Key specifications for MILU18250: Surface Treatment: ZINC OVERALL; Nominal Thread Size: 0.500 INCHES FIRST END IN; Thread Series Designator: NPT ALL ENDS; Material: STEEL OVERALL. 24 total characteristics are documented in the Federal Logistics Information System.

Validated with multiple authoritative sources, including Government, OEM, and Certified sources.
PartsTable Design LLC · partstable.com