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Reg. 264, Reg. 265 A,
Reg. 265 B
Additional tests before rejection |
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a)
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Should any of the
test specimens taken in accordance with Regs. 257 to 263
fail to meet the specified requirements one retest shall
be allowed for each specimen that fails, provided the
following minimum figures have been obtained:
| i) |
Reduction in area 30
per cent. |
| ii) |
Any other test except
the bend and impact tests, 90 per cent of the specified
requirements |
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| b) |
If a cold bend specimen should fail to meet the specified
requirements, two re-tests shall be taken from the same
test plate and these shall comply with the requirements
of Regulations 261
and 262.
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| c) |
If an Izod impact
test fails to meet the specified requirements, two re-tests
shall be taken from the test plate, one each side of the
original specimen and separated from it by not more than
5mm. Both re-tests shall show a minimum Izod impact test
value of 20 ft. lb. |
| d) |
If it be found there
is insufficient metal to permit the preparation of specimens
for re-test from the remainder of the test plate from
which the original specimen was taken the specimen for
re-test may be cut from the test plate relating to the
opposite end of the same longitudinal seam. |
Reg. 265
Non-Destructive Tests
(a) Micro and Macro Examination
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Micro
and macro examination – A specimen, the full thickness
of the plate and not less than 13mm wide may be taken
from each set of test plates by the Inspecting Authority
for the purpose of micro and macro
examination.
Macro-etching
of a complete cross-section of the weld including the
heat effected zone, should show satisfactory
penetration, fusion and absence of significant
inclusions or other defects.
In case of a doubt as to the condition of the
weld as shown by micro-etching, the area concerned is to
be microscopically examined for defect investigation.
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Reg. 265
(b) Radiographical Examination
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Every portion of the longitudinal and circumferential
welded joints of the drums shall be subjected to radiographical
examination or ultrasonic examination. Where ultrasonic
examination is used, it shall be demonstrated to the
satisfaction of the Inspecting Authority that the equipment
and the technique used are satisfactory. The manufacturer
shall ensure that the operator employed is competent
to use the equipment, apply the technique and interpret
the results of the examination.
The method employed in obtaining the radiographs shall
be such as to show clearly defects having a magnitude
equal to 2 per cent of the thickness of the welded joint.
To determine whether this result is being obtained and
indicator of approved form which includes a portion
equivalent to not more than 2 per cent of the joint
thickness, shall be placed in the vicinity of the weld
so as to make a record on each radiograph.
Each section of every weld shall be marked so that the
radiographs can be easily correlated to the particular
part of the joint represented.
The examination shall be made from the original films
and the acceptability of the welds shall be decided
by the Inspecting Authority. The welds deemed unsatisfactory
shall be rejected or dealt with under Regulation
266 and be radiographed again.
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