Use characteristics: The main use performance and use range of the valve are determined.

The use characteristics of the valve are: valve category (closed-circuit valve, regulating valve, safety valve, etc.); product type (such as gate valve, globe valve, butterfly valve, ball valve, etc.) ; Material of the main parts of the valve (valve body, bonnet, valve stem, disc and sealing surface); valve transmission mode, etc.

Structural characteristics: It determines some structural characteristics of valve installation, repair and maintenance methods, which belong to structural characteristics: structural length and overall height of valve, connection form with pipeline (flange connection, threaded connection, clamp connection, external thread connection, welding end connection, etc.); The form of sealing surface (insert ring, thread ring, surfacing welding, spray welding, valve body); Structure of valve stem (rotating rod, lifting rod), etc.