Investment Casting Check Nut
What are Investment Casting Check Nut?
A Check Nut, also known as a lock nut, is a hexagonal nut used to secure a threaded connection by preventing it from loosening due to vibration or torque. Commonly paired with fittings like bushings or adapters, it serves as a mechanical lock to reinforce threaded joints.
Made via the investment casting process, check nuts are dimensionally precise, corrosion-resistant, and provide reliable mechanical backup in instrumentation and piping systems.
Key Features
- Locks Threaded Connections – Prevents loosening under vibration or thermal expansion.
- Reinforces Fitting Stability – Used as a secondary nut to retain positioning.
- Compact Hex Design – Allows easy tightening in limited spaces.
- Corrosion-Resistant Materials – Suitable for harsh environments.
- Investment Cast Finish – Superior surface finish and dimensional accuracy.
Specifications
Mechanical Properties
Chemical Composition
Equivalent Grades
Weight Chart
Specifications
| Parameter | Details |
|---|---|
| Sizes | ¼" to 2" |
| Thread Standards | BSP / NPT / Metric |
| Material Options | SS 304, SS 316, CF8, CF8M |
| Standards | ISO 4144, ASME B16.11, MSS-SP-95 |
| Manufacturing | Investment Cast + CNC Machined |
| Property | Typical Value |
|---|---|
| Tensile Strength | 485 – 700 MPa |
| Yield Strength | 205 – 450 MPa |
| Hardness | 125 – 250 HB |
| Temperature Range | -46°C to +600°C |
| Element | Composition (%) |
|---|---|
| Carbon (C) | ≤ 0.08 |
| Manganese (Mn) | ≤ 2.00 |
| Silicon (Si) | ≤ 1.00 |
| Chromium (Cr) | 18.0 – 20.0 |
| Nickel (Ni) | 8.0 – 14.0 |
| Molybdenum (Mo) | 2.0 – 3.0 (in 316/CF8M) |
| Phosphorus (P) | ≤ 0.040 |
| Sulfur (S) | ≤ 0.030 |
| Iron (Fe) | Balance |
| Standard | Equivalent Grades |
|---|---|
| ASTM | A351 CF8 / CF8M, A182 F304 / F316 |
| ASME | B16.11 |
| MSS-SP | SP-95 |
| DIN | 2950 |
| ISO | ISO 4144 |
| Check Nut Type | Size (inches) | Weight per 100 pcs (kg) |
|---|---|---|
| Check Nut | ½" | 5.50 |
| Check Nut | 1" | 7.80 |
| Check Nut | 2" | 11.20 |
Applications of Investment Casting Check Nut
Construction &
Infrastructure
Automotive & Heavy
Equipment
Manufacturing &
Fabrication
Medical & Laboratory
Equipment
Electrical &
Electronics Assembly
Oil, Gas & Petrochemical
Installations
Do you have questions?
What’s the difference between a check nut and a standard nut?
A check nut is used in conjunction with another nut or fitting to lock the connection and prevent loosening.
Can check nuts be reused?
Yes, provided threads are intact and free of wear or corrosion.
Are check nuts suitable for high vibration environments?
Yes, they are specifically used for vibration-prone systems to maintain connection integrity.
Do you offer metric sizes or special threads?
Yes. Metric, NPT, BSP, and custom threading options are available on request.
