Description
125# Bronze Threaded Lock Nut
ASC / SCI FIG 36LN1 125# Bronze Threaded Lock Nuts provide a compact threaded locking component for compatible piping and mechanical connections.
Manufactured as part of the SCI Class 125 bronze fitting line, FIG 36LN1 features NPSL straight threads and bronze construction for securing compatible threaded components in position.
Product Highlights
- ASC / SCI FIG 36LN1
- Class 125 bronze fitting
- NPSL straight threads
- Threaded lock nut design
- 100% air tested
- Independent lab verified
Technical Specifications
| Product Type | Threaded Lock Nut |
|---|---|
| Brand | ASC / SCI |
| Figure | 36LN1 |
| Fitting Class | Class 125 |
| Material | Cast Bronze |
| Bronze Alloy | UNS C83600 |
| Material Standard | ASTM B62 |
| Configuration | Threaded Lock Nut |
| Thread Type | NPSL Straight Pipe Thread |
| Fitting Standard | AWWA C800 |
| Dimensional Standard | ASME B16.15 |
| Testing | 100% Air Tested |
| Quality Verification | Independent Lab Verification of Applicable Chemical & Physical Properties |
Construction Details
FIG 36LN1 is manufactured as a Class 125 cast bronze threaded lock nut for use with compatible threaded piping and mechanical connections.
Unlike tapered NPT fittings, FIG 36LN1 uses NPSL straight pipe threads. The straight-thread configuration allows the lock nut to advance along a compatible male-threaded component for positioning and mechanical locking.
SCI identifies FIG 36LN1 as 100% air tested with independent laboratory verification of applicable chemical and physical properties.
Design & Typical Applications
Lock Nut Design
- NPSL straight threads
- Compact nut configuration
- Bronze construction
- Threaded locking function
- Class 125 fitting family
Typical Applications
- Threaded piping assemblies
- Mechanical connections
- Equipment connections
- Industrial piping
- Compatible utility systems
Installation & Selection Considerations
- Confirm the required thread size.
- Verify NPSL thread compatibility.
- Confirm the mating component.
- Tighten against the locking surface.
- Verify system requirements.

Use the supplied SCI Bronze Fittings document to review FIG 36LN1 item numbers, NPSL thread information, and product details when selecting the correct 125# bronze threaded lock nut.
Need Help Selecting a 125# Bronze Threaded Lock Nut?
Need help confirming thread size, NPSL compatibility, bronze material requirements, or the correct lock nut for your application? The GetPipe.com Team can help.
Frequently Asked Questions
What is the figure number for this bronze threaded lock nut?
The ASC / SCI 125# Bronze Threaded Lock Nut is FIG 36LN1.
What type of threads does FIG 36LN1 use?
FIG 36LN1 uses NPSL straight pipe threads.
What is a threaded lock nut used for?
It threads onto a compatible male-threaded component and can be tightened against a mating surface to help secure the assembly in position.
Are NPSL threads the same as NPT threads?
No. NPSL threads are straight or parallel pipe threads, while NPT threads are tapered.
What material is FIG 36LN1 made from?
FIG 36LN1 is manufactured from bronze as part of the SCI Class 125 bronze fitting family.
Is FIG 36LN1 air tested?
Yes. SCI identifies FIG 36LN1 as 100% air tested.
Is the bronze lock nut lead-free?
The standard C83600 bronze construction is not identified as lead-free. Confirm applicable material requirements when selecting components for regulated potable-water service.
What should I confirm before ordering?
Confirm nominal size, NPSL thread compatibility, mating component requirements, and the intended application.
Important Ordering & Installation Notes
- Confirm the required thread size.
- Verify NPSL thread compatibility.
- Confirm the mating component.
- Do not assume lead-free compliance.
- Verify intended system service.