his Standard specifies the pipe fittings having longitudinal seams to be fitted by
butt-welding, mainly to pressure service pipings , high temperature service pipings ,
alloy steel pipings , stainless steel pipingsand low temperature service pipings (here-
after referred to as "pipe fittings").
The special quality specification, a part of or all of which may be designated by the
agreement between the purchaser and the manufacturer, is given in .Annex JA and the
requirements of special pttinge are specified in Aneex JB: The shapes and
dimensions of special bevel ends are described in Annex JC for informative reference.
NOTE 1 The pipe fittings covered by this Standard include those manufactured
from welded steel pipes.
NOTE 2 The efficiency of pipe fittings shall be taken into consideration, depending
upon the designing conditions.
NOTE 3 The International Standards corresponding to this Standard and the
symbol of degree of correspondence are as follows.
ISO 3419 : 1981 Non-alloy and alloy steel butt-welding fittings
ISO 5251 : 1981 Stainless steel butt-welding fittings (Overall evaluation:
MOD)
The symbols which denote the degree of correspondence in the con-
tents between JIS and the corresponding International Standards are
IDT (identical), MOD (modified), and NEQ (not equivalent) according
to ISO/IEC Guide 21.
Notes 1) Pipings using the carbon steel pipes for pressure service specified in JIS G 3454.
2) Pipings using the carbon steel pipes for high temperature service specified in JIS G 3456.
3) Pipings using alloy steel pipes specified in JIS G 3458.
4) Pipings using the stainless steel pipes specified in JIS G 3459 (excluding HTP) and stainless steel pipes specified in JIS G 3468.
5) Pipings using the steel pipes for low temperature service specified in JIS G 3460.