SS Lock Nut

Stainless steel lock nuts (jam nuts) are thin hex nuts per ISO 4035 / DIN 439, tightened flat against a mating surface to create thread back-pressure that resists loosening under vibration. All-metal A2 and A4 construction with no nylon insert.

Specification #

Dimension #

• All dimensions in mm, tolerance +/- 0.01 mm. Additional dimensions available on request.

Benefits #

Lock nuts solve fastener self-loosening in bolted joints exposed to vibration and dynamic loads. Unlike nylock nuts, they rely on all-metal thread distortion, serrations, or a double-nut tightening action rather than a polymer insert. The thin profile allows the nut to be tightened flat against a mating surface or secondary nut, generating high back-pressure on the threads that prevents rotational movement. This all-metal construction withstands temperatures of several hundred degrees, making lock nuts suitable for exhaust systems, heat exchangers, and other high-thermal environments where nylon inserts would degrade. They are immune to oil, fuel, and industrial solvents, and maintain friction performance across repeated installation cycles without degradation. Stainless steel A2 and A4 grades provide corrosion resistance in atmospheric, marine, and chemical service.

Common Applications #

Stainless steel lock nuts are used in bolted connections where vibration resistance, heat tolerance, and reusability are required.

• Automotive and vehicle suspension components
• Machinery and equipment subject to vibration
• Marine and shipbuilding hardware
• Rail and transportation systems
• Electrical and electronic enclosures
• HVAC and mechanical systems
• Industrial equipment and manufacturing
• Agricultural and heavy equipment
• Structural connections subject to dynamic loads
• Robotics and automation equipment