Stainless steel full-threaded threaded rod is a kind of uniform spiral convex shape on the cross-section of the solid outer or inner surface, and the fit of threaded fasteners refers to the degree of tightness between the threads that are screwed together, and the grade is Refers to the combination of deviations and tolerances on internal and external threads.
For inch threads, there are three levels of external threads: 1A, 2A, and 3A. There are three levels of internal threads: 1B, 2B, and 3B, all of which belong to clearance fits. The higher the level, the tighter the fit. For inch threads, the deviation of 3A grade is 0, and the deviation of 1A and 2A is the same.
The 1A and 1B grades are very loose tolerance grades, which are suitable for the tolerance matching between external and internal threads; 2A and 2B are the most common tolerance grades for inch mechanical fasteners; 3A and 3B can be screwed into The tightest fit is generally used for fasteners with tight tolerances and a critical safety design.
There is a matching tolerance between the 1A and 2A grades of the stainless steel full-threaded rod, and the 3A grade does not. Under normal circumstances, the tolerance of the 1A grade is 50% larger than the 2A grade and 75% larger than the 3A grade. ; The tolerance of internal thread 2B class is 30% larger than 2A class, 1B class is 50% larger than 2B class, and 75% larger than 3B class.
