Hex Jam Nuts
What is a Hex Jam Nut?

A Hex Jam Nut is a thin, six-sided internally threaded fastener used as a locking nut when paired with a standard hex nut. It is typically tightened against the primary nut to prevent loosening due to vibration or dynamic loads. Hex jam nuts are widely used in assemblies where space is limited, or where secondary locking strength is required without the use of chemical adhesives or washers.
Ideal for automotive, industrial, and machinery applications, hex jam nuts provide a low-profile solution for secure, vibration-resistant fastening.
Key Features
- Low-Profile Design – Thinner than standard hex nuts, ideal for tight spaces.
- Locking Function – Used as a jam nut to lock a primary nut in place.
- Thread Compatibility – Available in coarse and fine thread options.
- Material Versatility – Manufactured in carbon steel, stainless steel, brass, and more.
- Reusable – Can be installed and removed without damage to threads.
Specifications
Mechanical Properties
Chemical Composition
Equivalent Grades
Weight Chart
Specifications
Parameter | Specification |
---|---|
Size Range | M3 to M64 |
Thread Types | Metric, UNC, UNF, BSW, BSF |
Manufacturing Methods | Cold Forged, Hot Forged, CNC Machined |
Material Options | Carbon Steel, Alloy Steel, Brass, Stainless Steel |
Standards | DIN 439, ISO 4035, ASTM A563, BS 1768 |
Finishes Available | Zinc Plated, Galvanized, Black Oxide, Phosphate |
Property | Value |
---|---|
Proof Load | 400 – 900 MPa (grade-specific) |
Hardness | 100 – 300 HB |
Elongation | 10% – 20% |
Temperature Range | -50°C to 300°C |
Element | Percentage (%) |
---|---|
Carbon (C) | 0.42 – 0.50 |
Manganese (Mn) | 0.60 – 0.90 |
Silicon (Si) | 0.10 – 0.35 |
Phosphorus (P) | ≤ 0.040 |
Sulfur (S) | ≤ 0.050 |
Iron (Fe) | Balance |
Standard | Equivalent Grade |
---|---|
ASTM | A563 |
DIN | 439 |
ISO | 4035 |
JIS | B1181 |
BS | 1768 |
Nut Size (mm) | Thread Pitch (mm) | Weight (kg) |
---|---|---|
M6 | 1.0 | 0.35 |
M8 | 1.25 | 0.65 |
M10 | 1.5 | 1.10 |
M12 | 1.75 | 1.80 |
M16 | 2.0 | 3.40 |
M20 | 2.5 | 5.30 |
Applications of Hex Jam Nuts
Construction &
Infrastructure
Automotive & Heavy
Equipment
Manufacturing &
Fabrication
Medical & Laboratory
Equipment
Electrical &
Electronics Assembly
Oil, Gas & Petrochemical
Installations
Do you have questions?
How does a hex jam nut work?
A hex jam nut is tightened against a standard nut to "jam" it in place, preventing it from loosening under vibration or motion.
Can hex jam nuts be used on their own?
While they can be used independently in low-load applications, their main purpose is to serve as a secondary locknut.
Are hex jam nuts available in stainless steel?
Yes, we offer jam nuts in various materials including stainless steel grades 304 and 316 for corrosion resistance.
Do you supply jam nuts in bulk for industrial use?
Absolutely. Bulk orders are available with full documentation, test certificates, and export packaging as required.
