unified thread thread level , marking methods and limit size

unified thread thread level , marking methods and limit size
Rating: unified thread provides six different levels, namely 1A, 2A, 3A ( male ) and 1B, 2B, 3B level ( internal thread ) . Where the suffix A and B denote external and internal threads . 1A and 1B grade Hydraulic adapters thread is for weapons and some special requirements prescribed , which requires quick and easy assembly or threaded slight damage and stains can also be fitted occasions you can use this thread . 2A and 2B is a general purpose grade threaded bolts, screws , nuts and similar threaded fasteners of the most commonly used standard thread . Class 3A and 3B threaded for threaded fitting tightness and lead , half-width of the high precision of the occasion. 3A and 3B thread only with the accuracy level device , the effective measurement and detection means to get.