What is the difference between API 623 and API 602?
API 623 and API 602 are two different American Petroleum Institute (API) standards that apply to different valve types and application scenarios.
API 623:
Scope of application: The standard is mainly used for needle valves used under high temperature and high pressure conditions.
Main content: including design, materials, manufacturing, inspection and performance requirements. Specifically addresses the safety performance of valves at high temperatures (over 1000°F or 538°C) and high pressures (over 2500 psi or 17.2 MPa). The standard also specifies requirements for valve dimensions, connections, operation, and related parts.
API 602:
Scope of application: The standard applies to steel pipe flanges and valves with flanged connections, including ball valves, gate valves, check valves and globe valves.
Main content: mainly related to the design, manufacture and quality certification of valves. The standard specifies the dimensions, connections, materials and test methods of the valves.
To summarise, API 623 focuses on the specific requirements for needle valves under high temperature and high pressure conditions, whereas API 602 covers flanged connections and manufacturing requirements for different types of valves more broadly.