BS 4638:1970

This standard BS 4638:1970 Specification for carbon steel wire for zigzag and square-form springs is classified in these ICS categories:

• 77.140.25 Spring steels

1.1 This British Standard specifies the requirements for patented cold drawn plain carbon steel round wire, suitable for forming into zigzag and square-form springs used in the production of seat and back units for cars and certain types of domestic upholstery. Wire to this standard is not intended for use in the manufacture of mechanical springs.

The definition of patenting is given in BS 6562-1.

1.2 The standard includes preferred metric sizes of wire for the two types of spring and gives a choice of tensile strength ranges.

Requirements for patented cold drawn plain carbon steel round wire in three grades of tensile strength. Chemical composition, standard sizes and tolerances, methods of testing, mechanical properties and details of packing and identification.