Technical description

The nuts offered are threaded fasteners designed for mechanical assemblies subject to the specific stresses of the railway environment: vibrations, shocks, significant temperature variations and intensive maintenance cycles. They are made of treated steel, stainless steel or alloy depending on the application requirements, and cover the common strength classes (8, 10, 12) according to ISO 898-2.

The range includes the following types:

• Standard hexagon nuts (ISO 4032 / DIN 934) are the basic reference for general assemblies on structures, casings and mechanical equipment.
• Lock nuts (Nylstop, Écotop or all-metal types) incorporate an anti-loosening system, which is essential on equipment subject to the continuous vibrations characteristic of railway traction.
• Slotted nuts allow mechanical locking by means of a pin or lock washer and are used on shafts, bearings and assemblies requiring maximum security against loosening.
• Cap nuts protect the threaded end of the shaft or bolt against debris, corrosion and impact, particularly in exposed areas under the body.
• Wheel and axle nuts meet the specific requirements of wheel and bogie assemblies, with high tightening torques and strict tolerances.

Variations

Nuts are available in common metric sizes (M8 to M64) as well as in fine pitch threads according to manufacturer specifications. Available materials include heat-treated steel, A2 and A4 stainless steel, and alloy steel for high strength grades. Surface treatments include electrolytic zinc plating, Geomet and raw finishes, depending on the corrosion requirements of the specifications.

Applications

The nuts in this range are used in all railway motorisation equipment: fastening gearbox and transmission casings, assembling engine mounts on bogies, clamping underframe equipment, mounting axle bearings and fastening suspension components. They are also used in periodic maintenance operations as systematic replacement parts during servicing.