ISO 8521-2020 pdf download.Glass-reinforced thermosetting plastic (GRP) pipes一Test methods for the determination of the initial circumferential tensile wall strength.
9.3.1 Measure the width, b, of the test piece.
9.3.2 Fix the test piece in the grips so that the load will be applied through the centreline of the test piece (see Figure 5). The sample shall be clamped at the inner and outer surface, onto the added thermosetting resin.
9.3.3 Apply a constant separating speed to the grips so that failure occurs between 1 mm and 3 mm. Record the maximum force and the time to failure. When using test pieces in accordance with case 2, failures not occurring in the notched area shall be disregarded.
9.4 For method D
9.4.1 Measure the width, b, of the test piece.
9.4.2 Fix the test piece in the grips (see Eigure6) so that the force is applied through the centreline of the test piece. The sample shall be clamped at the cut sides. When fixing the test piece in the grips, take care to ensure that the midpoint of the test piece is located at approximately the midpoint of I,,.
9.4.3 Apply a constant separating speed to the grips so that failure occurs between 1 mm and 3 mm. Record the maximum force and the time to failure. When using notched test pieces, failures occurring outside the notched area shall be disregarded.
9.5 For method E
9.5.1 Measure the width, b, of the test piece.
9.5.2 Fix the test piece in the grips and align the restraining fixture so that no bending occurs in the test piece. Position the test piece so that its centreline is coincident with the loading axis of the machine.
9.5.3 Apply a constant separating speed to the grips so that failure occurs between 1 mm and 3 mm. Record the maximum force and the time to failure. When using test pieces in accordance with case 2, failures not occurring in the notched area shall be disregarded.
9.6 For method F
9.6.1 Measure the width, b, of the test piece and the winding angle. 0. Determine by measurement and/ or calculation of the radius, r.
9.6.2 Position the test piece so that its centreline is coincident with the loading axis of the machine.
9.6.3 Apply a constant separating speed to the grips so that failure occurs between 1 mm and 3 mm. Record the maximum force and the time to failure.
Disregard the result of any test piece that does not break across the neck.ISO 8521 pdf download.