The use of screw gauges is determined by JIS standards. Use the gauge of the thread type in the drawing instructions and inspect the screw in a determined manner. Tapered screws for pipes (PT, R, Rc, Rp) used for piping, etc., are screwed into the gauge until the screw stops, and if the pipe end of the screw to be inspected is within the range of the maximum and minimum notches, it is judged that the fit inspection has passed.



[How to use tapered screw plug gauge for pipes]

Gauge Symbols	TG	TG
kind	PT	R
standard	Former JIS	ISO
Screw to measure	PT & PS	RC/Rp
use	If the pipe end is within the notch range of the gauge, it will pass.
Passing range
Number of notches	1	2
other	Rc and Rp gauges are displayed as "R" No GO/NO GO setting No distinction between machinig and inspection No precision

In addition, both the tapered internal thread Rc and the parallel internal thread Rp gauge use R tapered plug gauges as gauges.


[How to use tapered thread ring gauge for pipes]

Gauge Symbols	TG	TG
kind	PT	R
standard	Former JIS	ISO
Screw to measure	PT	R
use	If the pipe end is within the notch range of the gauge, it will pass.
Reference Diameter Position
Passing range
other	There is no difference in the number of notches. There is a difference in the thickness of the gauge No distinction between machining and inspection No precision

Tapered screws for pipes do not have the same distinction as parallel screws due to thread accuracy. There is only one.

Since the shape and tolerance are different, both the plug gauge and the ring gauge cannot be shared.

Use the thread type gauge in the drawing instructions.