JSA - JIS B 0254
Limit gauges for parallel pipe threads
|Publication Date:||22 March 2011|
|ICS Code (Measuring instruments):||17.040.30|
|ICS Code (Special screw threads):||21.040.30|
This Standard specifies the limit gauges to be used for dimensional inspection of parallel pipe threads (G) specified in JIS B 0202 and gauges to be used in their checkIng.
The limit gauges for screw threads and checking gauges are generically referred to as "gauges"
The gauges applicable to the parallel pipe threads (PF) specified in Annex of JIS B 0202 are specified in Annex JB.
Depending on the applications of the machined pieces, additional checks may be carried out using measuring instruments other than these gauges:
a) the threaded GO gauges shall ensure that the profile of the machined piece does not exceed the maximum of material provided for by the tolerances applied to the dimensions of the profile defined by JIS B 0202;
b) the threaded NOT GO gauges for the threads of the pieces fix the minimum material limit on the flanks of the thread.
NOTE: The International Standard corresponding to this Standard and the symbol of degree of correspondence are as follows:
ISO 228-2 : 1987 Pipe threads where pressure-tight joints are not made on threads - Part 2 : Verification by means of limit gauges (MOD)
The symbols which denote the degree of correspondence in the contents in the corresponding International Standard and JIS are IDT (identical), MOD (modified) and NEQ (not equivalent) according to ISO/lEC Guide 21-1.