該產品是在導入ISO規格之后按照JIS標準所生產，用于檢查不要求密封性的機械連接為主要目的的螺紋。和遺忘的管用平行螺紋量規的相差點如下：使用方法為：界限螺紋量規的通規可依輕松的穿過止規的    螺紋擰進不到2圈的話，這樣測量等級則是合格的。

      Pipe with parallel thread coming under the ISO standard,where the main purpose is liquids but a tight mechanical.Connection is not requied,is inspected using a  parallel limit Gauge (G).This includes such items as pipe connections.Plumbingparts and equipment to handle liquids.

（1） 等級的有無

● 內螺紋用的螺紋量規等級是沒有的。

● 外螺紋用的螺紋量規區分為A級和B級，只要GR是A級B級共用的，

Tolerance class on thread plug gauges is unspecified.

However there are two classes (A and B) for thread ring gauges.The GR(GO) is commonly used for the A and B classes.

（2） 通端和止端沒有檢查用和加工用的區別

               Go and not go of the ISO gauge system is made with same dimentions for both inspection and working.

（3） 判定螺紋環規是否合格。

               GR、NR等，根據通規或止規兩端的插頭（GRGF,GRNF,NRGF,NRNF）來檢查。

               For the ISO class gauge system,the thread gauge for check fitting of the thread ring gauge is the GO and NOT GO limit type.

（4） 磨損點檢查的插頭。

       NR用的磨損點檢塞規(NW)是新導入的。

                New barjone wear check plug for NOT GO thread ring gauge.