BS 7371-9:1996

Coatings on metal fasteners. Specification for phosphate or phosphate and oil coatings | Status: Confirmed, Current

1 Scope This Part of BS 7371 specifies requirements for phosphate or phosphate and oil coatings on metal fasteners and accessories, applied by immersion or spraying.

NOTE 1 Phosphate coatings are primarily intended for application to ferrous, zinc or zinc alloy fasteners.

NOTE 2 Phosphate coatings can be used as an undercoat to improve the corrosion resistance and adhesion of a subsequently applied top coat (e.g. organic coating).

NOTE 3 Phosphate coatings can be used to impart a controlled torque/clamping force relationship to a threaded fastener (see BS 7371: Part 2: 1993).

This Part of BS 7371 should be read in conjuction with the requirements for phosphate and phosphate and oil coatings of BS 7371: Part 1General requirements and selection guidelines. This Part of BS 7371 also specifies requirements for the following:

1. a) athe minimum coating mass per unit area;
2. b) assessment of the corrosion resistance of unused coated parts when subjected to neutral salt spray testing (see for example BS 7479:1991).