NF EN ISO 8233, T54-083 (03/2024)

This document specifies a test method for determining the opening, closing and operating torque of valves made of thermoplastic materials. This document applies to all types of manually operated valves made of thermoplastic materials, with or without actuator, intended to be used for the transport of fluids. NOTE 1 Examples of types of valves tested with this method are in ISO 4437-4, ISO 16135, ISO 16136, ISO 16138, ISO 16139, ISO 16486-4, ISO 21787, EN 1555-4[13] and EN 12201-4[14]. This document does not specify the relationship between the operating torque and its possible increase after prolonged use of the valve under specific operating conditions or after wear/chemical attack on the materials. NOTE 2 Concerning the chemical attack on materials, a set of data is available in ISO/TR 10358 concerning the endurance test necessary to confirm the ability of valves made of thermoplastic materials operated by hand to withstand prolonged use , with repeated opening and closing maneuvers. Additional information is given in ISO 8659.
(Automatic translation from French)