ISO/TC 58/SC 2/WG 4 - Valve stem and cylinder neck threads

This document specifies definitions, dimensions and tolerances of parallel screw threads of M30 x 2, M25 x 2 and M18 x 1,5, for the connection of valves to medical and industrial gas cylinders. This document does not contain the connection requirements for: —   mechanical strength; —   gas tightness; —   capability of repeated assembly and dismounting operations (this aspect is covered in ISO 13341).

ISO 11363-1:2018 specifies dimensions and tolerances for taper screw threads of nominal diameter 17,4 mm (designated as 17E) and 25,8 mm (designated as 25E) used for the connection of valves to gas cylinders. ISO 11363-1:2018 does not cover the connection requirements for - mechanical strength, - gas tightness, and - capability of repeated assembly and dismounting operations. Gauge inspection is covered by ISO 11363‑2.

ISO 11363-2:2017 specifies types, dimensions and principles of use of gauges, to be used in conjunction with the taper threads specified in ISO 11363-1 (i.e. 17E and 25E threads). It provides examples of calculations for thread gauge dimensions on the large end diameter (Annex A) and draws attention to the limitations of the gauging system specified (Annex B).

ISO 11363-2:2010 specifies types, dimensions and principles of use of gauges, to be used in conjunction with the taper threads specified in ISO 11363-1 (i.e. 17E and 25E threads). It provides examples of calculations for thread gauge dimensions on the large end diameter and draws attention to the limitations of the gauging system specified.

ISO 11363-1:2010 specifies dimensions and tolerances for taper screw threads of nominal diameter 17,4 mm (designated 17E) and 25,8 mm (designated 25E) used for the connection of valves to gas cylinders. It does not cover the connection requirements for: mechanical strength; gas tightness; capability of repeated assembly and dismounting operations. Gauge inspection is covered by ISO 11363-2.