Classification of thread

1 thread since the beginning and external threads two kinds ;
2 Press tooth shape can be divided into : 1 ) Triangle thread 2 ) trapezoidal thread 3 ) Rectangular thread 4 ) Buttress ;
3 Press the number of lines of  Hydraulic adapters single thread and multiple thread ;
4 Press screwed into the direction of the left-hand thread and right-hand thread of two kinds, dextral not marked , L plus LH, such as M24 × 1.5LH;
5 Press to different purposes are: Metric common thread with thread sealing pipe thread , non- thread sealing pipe thread , 60 ° taper pipe thread, Metric taper thread , etc.