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Reg. 610, Reg. 611 A, Reg. 611
B
QUALIFICATION
TESTS FOR WELDERS ENGAGED IN WELDING OF BOILERS AND STEAM-PIPES
UNDER CONSTRUCTION, ERECTION AND FABRICATION AT SITE IN INDIA
AND IN REPAIRING BOILERS AND STEAM-PIPES BY WELDING
Reg 610
Tests for Requalification
At a
requalification test a welder need not be examined in theoretical
subjects, but he shall be required to qualify in the following
practical tests:-
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| a) |
Plate
Welding.-
A groove welded joint of two pieces of plates not less
than 16 mm. (5/8 inch) thick over a length of 152 mm.
(6 inches) in a position 45 degree to vertical, size of
plates to be welded being 229 mm. x 152 mm. (9 inches
x 6 inches). The main welding is to be carried from the
underside only.
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| (b) |
Pipe
Welding.-
The material of plates, tubes, pipes
and electrodes used for these tests shall conform to the
requirements of appropriate Regulations as may be applicable
in each case.
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(i) |
A groove
welded joint with the axis of the pipe in a horizontal
position and without rotating the pipe. |
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(ii) |
One
weld of a branch to a pipe, as prescribed in Regulation
609. |
| (c)
(d)
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Tube
Welding.-
A butt welded joint of two pieces of boiler tubes with
the axis in a vertical position, and tubes of same size
fixed in adjoining positions. This test shall be in addition
to the test for pipe welding under clause (b).
When a welder is continuously engaged on production
weld, tests on the work in actual production to the
satisfaction of the Competent Authority may be accepted
as an alternative to the tests prescribed as above under
clauses (a), (b) and (c).
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Reg. 611
Examination of test specimens for initial
qualification tests:-
(a) Groove welded plate specimens
The Groove welded
plate specimens after welding may be lightly pressed cold
to remove any distortion due to welding. The test specimen
shall be similarly treated as required for the actual
production weld.
After visual examination, the welded specimen shall be
subjected to radiographic examination in the manner as
provided in
Regulation 265 (b), provided that this requirement
may be waived when the welder is to be engaged on production
work where radiographic examination is not required under
these Regulations.
Thereafter test pieces shall be marked and cut out in
order shown in Figure XIII/1.
The bend test specimens (B1 & B2) shall be prepared
and tested as per Regulations
261 & 262.
In the case of alloy steel specimen, the angle of the
bend is to be decided by the Competent Authority, provided
that the angle shall, in no case, be less than 120°.
Two each specimens (E1 & E2) shall be prepared, one
for micro and the other for macro examination as per Regulations
265(a).
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(b)
Fillet welded plate specimens.-
The dimensions and
preparation of the fillet-weld test specimen shall
conform
to Figure XIII/2. The test specimen shall not contain
any visible cracks. It shall be cut transversely to provide
a centre section (254 mm) (10 in.) long and two end sections
each approximately (25 mm) (1 in.) long.
The stem of the (254 mm) (10 in.) centre section shall
be loaded laterally in such a way that the root of the
weld is in tension. The laod shall be steadily increased
until the specimen fractures or bends flat upon itself.
In order to pass the test.-
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| (1) |
The specimen shall
not fracture, or |
| (2) |
If it fractures,
the fractured surface shall show no evidence of cracks
or incomplete root penetration, and the sum of the lengths
of inclusions and gas pockets visible on the fractured
surface shall not exceed (51 mm) (2 in.).
The cut end of one of the end sections shall be polished
and etched with a suitable reagent to give a clear definition
of the structure of the weld. |
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In order to pass
the test:- |
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(i) |
Visual examination
of the cross section of the weld shall show complete fusion
at the root and freedom from cracks. |
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(ii) |
The weld shall not
have a concavity or convexity greater than (1.6 mm.) (1/16
in.); and |
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(iii) |
There shall be not
more than (1.6 mm) (1/16 in.) difference in the lengths
of the legs of the fillet. |
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