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Reg. 261, Reg. 262,
Reg. 263
Bend Test Pieces |
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a)
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One for direct and
one for reverse bending shall be taken transversely to
the weld and where the thickness of the plate permits,
one should be above the other. The specimens shall be
rectangular in section so as to have width equal to one
and half times the thickness of the specimen but not less
than 30 mm. The surface of the specimens shall be machined
just to remove the surface irregularities of the plate
and the weld. The corners of the specimens shall be rounded
to a radius not exceeding 10% of the thickness of the
specimen. |
| b) |
Where plate thicknesses do not exceed, 1¼ in.
the thickness of the specimen shall be equal to the
full thickness of the test plate. Where the plate thickness
exceeds 1¼ in. the specimen shall in all cases
have a thickness of at least 1¼ in. The specimen
to be tested with the outer surface of the weld in tension
shall be prepared by cutting to waste the metal local
to the inner surface of the weld so that the desired
specimen thickness is obtained (see
Fig.20, Specimen
A). the specimen to be tested with the inner surface
in tension shall be prepared by cutting to waste the
metal local to the outer surface of the weld so that
the desired specimen thickness is obtained (see Fig.20,
Specimen B). Where the thickness of the plate permits,
both specimens may be cut from the same piece of plate,
the specimen being located in the plate one above the
other (see Fig.
20, Specimen C).
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Reg. 262
Bend Tests
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The specimen shall be mounted in such a way that the
axis of the former is in the middle of the weld, and
on roller supports the faces of which are separated
by a distance determined by the thickness of the specimen.
The test specimen shall be pushed through the supports
by a former having a diameter also determined by the
thickness of the specimen. The requirements of the Table
below, relating to the thickness of the test specimen
shall apply.
Table: Bend Test Requirements
| Specified minimum
tensile strength of plate |
Diameter
of former |
Free space between
supports at the end of test |
| Below 44 kgf/mm² |
2t |
4.2t |
| From 44 to 54 kgf/mm² |
3t |
5.2t |
| Above 54 kgf/mm² |
4t |
6.2t |
On completion of the test, no crack or
defect on the outer surface of the specimen shall be
greater than 1.5 mm measured across the specimen, or
3 mm measured along the specimen. Premature failure
at the corner of the specimen shall not be considered
as a cause for rejection.
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Reg. 263
Notched-Bar Impact Tests
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The notched bar impact test specimens are to be one
of the two types and dimension shown in figure
21A and 21B. The notch shall be contained in the weld-metal
at approximately the axis of the weld and the axis of
the notch is to be perpendicular to the surface of the
plate.
| The test shall
be carried out as follows:- |
| For the U-Notch
specimen at a temperature of 20 ± 2°C. |
| For the V-Notch
specimen at a temperature of 50 ± 2°C. |
In the case of V-Notch specimen,
the machining of the bottom of the notch shall be
done very carefully.
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The choice between U-notch and V-notch specimen shall
be at the discretion of the Inspecting Authority. The
minimum result to be obtained from the Impact test pieces
shall be:
| a) |
U-notch specimen |
5.50 kgfm/cm² |
| b) |
V-notch specimen |
3.46 kgfm/cm² |
Note: Above values are equivalent to 2.76 kgfm
divided by sectional area below the notch.
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