1) The use classification is divided into:
Fastening screw thread, sealing screw thread, pipe screw thread, transmission screw thread, ordinary screw (or general purpose) thread, special screw thread, etc
2) Tooth type classification is divided into:
Trapezoidal screw thread, serrated screw thread, rectangular screw thread, triangular screw thread, short screw (or low) screw thread, 60 screw thread? And 55 lead screw? Thread, etc
3) The coordination nature or type method is divided into:
Transition fit screw thread, interference fit screw thread, clearance fit screw thread, "cone / cone" fit screw thread, "column / cone" fit screw thread, "column / column" fit screw thread, etc
4) Pitch or diameter classification: coarse screw thread, fine screw thread, ultra-fine screw thread, small screw thread, etc
5) Unit classification is divided into: British screw thread and metric screw thread
6) The inventor's surname or country of invention classification is divided into Wyeth screw thread, American screw thread, British screw thread, unified screw thread, etc
Among the above six classifications, the use classification is the more basic one
