(a) For testing, either the parts themselves shall be used
or additional material of sufficient size for test pieces
shall be available. In the case of headers for example, surplus
lengths for test rings may be used. In the case of flanges
swaged in dies, the punching left may be used as test pieces
in which case the identity of the material of the punching
with that of the flange shall be evidenced in an adequate
manner. The test may be performed also on the semi-finished
material for example a bar or a billet, provided it is given
approximately the same reduction and heat-treatment as the
finished forgings. For headers with closed ends, the test
rings shall be cut off before dishing or reducing and shall
be subjected to the same heat treatment as the headers themselves.
In the case of headers which are closed by special covers,
the test ring shall be cut off after heat-treatment. Similar
procedures shall be followed for test pieces of other forgings.
(b) For testing, piece of one and the same cast of the same
heat treatment batch as well as of similar dimensions may
be gathered into one group. At least one test piece shall
be made from each group.
(c) A proportional test piece with Lo = 5 do shall be used
as a test specimen.
(d) Tangential test piece shall be used for headers where
practicable. For headers with outside diameter less than 200
mm longitudinal test pieces may be allowed.
(e) Hydraulic Test.- A hydraulic test shall be carried out
at the Makers works in accordance with the requirements
of regulation 268,
if required by the Inspecting Authority.
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