Ball valves are the most commonly used valves for shut-off and diversion in industrial piping systems. Different industries and projects worldwide adopt different technical standards. Many procurement and process engineers get confused during the selection phase: which specifications should ball valves comply with, and what are the differences between various standards.
What is the ISO standard for ball valves? Among the many ball valve standards, a frequently asked question is: “What is the ISO standard for ball valves?” A key ISO standard for metal ball valves used in the petroleum, petrochemical and related industries is ISO 17292:2015, Metal ball valves for petroleum, petrochemical and related industries.
However, it is not the only ISO standard for ball valves; the applicable standard depends on the application.
This standard applies to metal ball valves with flanged, threaded, socket weld and butt weld ends, covering sizes from DN8 to DN600. It specifies all technical requirements including design construction, materials, pressure-temperature ratings, shell strength, seat sealing, marking and factory pressure testing. Serving as a global international benchmark widely adopted in chemical and oil & gas projects, it distinguishes full port and reduced bore ball valves, and sets clear constraints for anti-static construction, low-temperature service and hydrogen sulfide service.
Trunnion mounted ball valve and floating ball valve are the two mainstream structures of ball valves, and ISO 17292 covers both types of products.
Floating ball designs are mostly used for small-to-medium bore and medium-low pressure service; trunnion mounted ball valve designs are applied to large bore and high-pressure pipelines. Apart from ISO17292, long-distance oil & gas pipeline projects often additionally reference API 6D, the standard for pipeline valves, to strengthen testing and safety requirements for pipeline service.
Key standard points for full port ball valve is clearly defined in ISO 17292. The bore through the ball is approximately equal to the pipe internal diameter, offering minimum flow resistance, suitable for pigging and medium purging service.
During selection, note that the standard allows suppliers to also provide reduced bore ball valves, but the bore type must be clearly marked on nameplates and documentation to prevent procurement mismatch for projects.
Standard scope boundary for 2 piece ball valve features a split body construction, mostly used for small-to-medium bore threaded and flanged ball valves. ISO17292 includes 2 piece construction, but attention should be paid: some light-duty civil 2 piece ball valves do not fully meet all stringent industrial test requirements of ISO17292. For petrochemical and high-pressure projects, it is necessary to verify whether the manufacturer’s products fully perform shell and seat pressure tests as required by ISO17292.
Brief introduction to other mainstream international ball valve standards Besides the ISO system, commonly used American standards include API 6D (pipeline ball valves) and ASME B16.34 (valve pressure-temperature base).
Procurement documents should not simply state “ball valve standard”. The specific standard number, edition, as well as valve construction: floating ball / trunnion mounted ball, full port, body construction such as 2 piece ball valve, shall be clearly specified to avoid discrepancies between delivered products and project technical requirements.
