This Standard specifies the limit gauges used for the dimensional inspection of metric
screw threads specified in JIS B 0205-2 (hereafter referred to as "limit gauges for screw
threads"), and gauges used for checking and setting of them (hereafter referred to as
"check gauges and setting gauges") (The limit gauges for screw threads, the check gauges
and the setting gauges are collectively referred to as "gauges" simply).
Other inspection methods, for example, the measurement by the indicating instru-
ment may be used; however, the inspection using gauges specified in this Standard
always takes precedence.
This Standard aims to specify the means to discriminate the workpiece threads
within the permissible limit sizes from others.
The following principles shall apply to ensure the interchangeability of the workpiece
threads and to avoid disputes between the manufacturer and the purchaser.
a) The manufacturer shall not deliver any workpiece thread whose thread sizes (for
example, the single pitch diameter and the virtual pitch diameter) are outside the
permissible limit sizes.
b) The purchaser shall not reject any workpiece thread whose thread sizes (for ex-
ample, the single pitch diameter and the virtual pitch diameter) are within the
permissible limit sizes.
To satisfy these two principles, this Standard specifies classes and sizes of gauges
required for the inspection of screw threads, conditions for using these gauges, and the
inspection for the workpiece threads.
NOTE : The International Standard corresponding to this Standard is as follows.
ISO 1502"1996 ISO general-purpose metric screw threads-Gauges and
gauging (MOD)
In addition, symbols which denote the degree of correspondence in the
contents between the relevant International Standard and JIS are IDT
(identical), MOD (modified), and NEQ (not equivalent) according to ISO/
IEC Guide 21.