BS 2A 122; 2A 123; 2A 124:1981

This standard BS 2A 122; 2A 123; 2A 124:1981 Specification for clinch nuts (Unified threads) for aircraft is classified in these ICS categories:

• 49.030.30 Nuts

These British Standards cover the dimensions, material, finish, testing and identification of aircraft clinch nuts with Unified threads. According to the materials used in their construction the clinch nuts are classified as satisfactory for use at sustained temperatures within the following ranges:

1. −75°C to +200°C - Cadmium plated steel nuts;
2. −75°C to +125°C - Aluminium alloy, brass or bronze nuts.

NOTE. All nuts are capable of remaining effective for servicing operations at −40°C.