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1-1/4″ FNPT Stainless Steel Locknut — 304 SS, Class 150
Description
1-1/4″ FNPT SS Locknut is a corrosion-resistant stainless steel locknut designed for securing threaded fittings on pipe systems. Constructed from 304 stainless steel, it meets Class 150 specifications and is suited for a variety of pressurized and industrial piping applications.
Key Features & Specifications
- Nominal Pipe Size: 1-1/4″ (FNPT)
- Material: 304 stainless steel — offers good corrosion resistance and strength
- Connection Type: Female NPT (threaded internally)
- Class / Pressure Rating: Class 150 — up to 300 psi for typical liquid/air service
- Maximum Steam Pressure: 150 psi at rated temperature
- Standards / Conformance: Threads conform to ANSI B1.20.1, material meets ASTM A-351 standards
- Dimensions: Outside Diameter ~2-3/64″, overall length ~7/16″, hex across flats ~2-1/16″
- Applicable Media: Air, natural gas, non-potable water, oil, steam (within rating limits)
- Country of Origin: Vietnam
Applications & Benefits
- Used to lock or secure threaded mechanical joints in piping systems
- Adds stability and helps prevent loosening due to vibration or thermal cycling
- Suitable for industrial, plumbing, HVAC, and process systems requiring stainless steel components
- Compatible with various media (water, gas, oil, steam) when used within its pressure & temperature limits
