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Reg. 261
, Reg. 262, Reg. 263

Bend Test Pieces

a)

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).



Reg. 262

Bend Tests

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.




Reg. 263

Notched-Bar Impact Tests

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.

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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