AS 4617:2018 pdf free
AS 4617:2018 pdf free.Manually operated gas valves
All castings and hot pressings shall be clean and sound, free from laps, blow holes and pitting. All surfaces not machine finished shall be clean, smooth and free from sand.
Porous castings or cracks in gas-carrying parts shall not be sealed other than by an accepted method for the impregnation of castings, e.g. vacuum impregnation.
The assembled valve shall not contain dirt, casting sand, swarf or other foreign matter.There shall be no excess diaphragm dressing, lubrication or jointing compound in the valve.
Every part shall be secure against accidental displacement. Every part shall be constructed to maintain a fixed relationship between essential parts under normal and reasonable conditions of handling and usage so as to ensure continued conformance with this Standard.Holes intended for the assembly of parts or for mounting shall not open into gasways. Holes shall provide a minimum wall thickness of 1 mm from gasways.
Non- functional holes used for manufacture and which form a passage between gasways and the atmosphere shall be permanently sealed by mechanical means.
Self-tapping screws, other than those that form a fully swaged machine type thread, shall not be used to secure together the external joint of a gas-carrying component that may be removed in servicing. The application of thread-forming screws shall be limited to malleable materials. The application shall not result in deformation or cracking of the component.
Valves with a rated working pressure exceeding 14 kPa, which require the addition of lubricant or sealant to maintain gas tightness, shall be capable of having this added without dismantling the valve.
The tightening of a gland or any other adjustment shall not permanently affect the ability of the valve to meet the performance requirements of this Standard.
The valve operation shall travel through 90° and be gas tight from 85°. The operating lever or handle shall be attached to the valve so that it cannot be incorrectly assembled.AS 4617 pdf free download.
