1. Profiles after production and before carrying out acceptance tests shall be maintained at temperature (21±3)°C not less than 1 hour (control of marking and availability of a protective film is allowed to carry out in the course of production).
during periodic tests, and if the profiles have been stored (transported) at a temperature other than that specified before the test, they are conditioned at a temperature of (21±3)°C during the day.
tests shall be Carried out at a temperature of (21±3)°C.
2, unless otherwise specified. Marking and the presence of a protective film is checked visually.
3. When performing measurements of linear dimensions, as well as deviations from the shape of products are guided by the requirements of GOST 26433.0, GOST 26433.1.
4. The length of the profiles is measured on the five-dimensional segments of metal tape measure of the 2nd class of accuracy according to GOST 7502. The test result is considered satisfactory if four out of five (with repeated testing, nine out of ten) measurements meet the established requirements, and the result of the fifth (tenth) measurement differs from the established requirements for permissible deviations by no more than 50%.
5. The procedure for determining the quality of the cut length profiles set in the technological regulations.
6. The form deviation profile is determined at three metre intervals (samples). For the result of measurement of each parameter take the arithmetic mean value of the results of measurements of three samples. In this case, the value of each result should be within the limits of the tolerances set in 5.2.5.
7. Deviations from the straightness of the front walls of the profile along the cross section and from the perpendicular of the outer walls of the profiles of the boxes are measured by a probe, determining the largest gap between the profile surface and the side of the angle according to GOST 3749. To determine deviations from the parallelism of the front walls of the profile along the cross section, two metal rulers according to GOST 427 are used, which are pressed with edges one above the other perpendicular to the longitudinal axis of the sample. Measure the distance between the edges of the rulers of the caliper 100 mm in length. The magnitude of the deviation from the parallelism of the front walls is determined as the difference between the largest and smallest dimensions. Measurements are carried out at three points along the length of the sample. For the result of measurement for each sample take the value of the greatest deviation.
8. To determine deviations from the straightness of the profile sides along the length of the sample is applied alternately to all outer surfaces of the calibration plate and with a probe measure the distance between the profile and the surface of the calibration plate. The maximum value of this distance is taken for the magnitude of the deviation from the straightness. Note-for tests it is allowed to use the surface of any measuring instrument (for example, the construction level according to GOST 9416) with a flatness tolerance of not less than the ninth degree of accuracy according to GOST 24643.
9. The deviation of the nominal dimensions of the cross section is determined on five segments of the profile with a length of 50-100 mm. the Dimensions are measured at each end of the segment by a caliper according to GOST 166. It is allowed to carry out the control of deviations of nominal sizes of cross sections of profiles by means of optical and other devices, providing measurement accuracy of 0,1 mm.in this case, the length of the segments is set in accordance with the technical characteristics of the test equipment.
for the test result for each measurement parameter take the arithmetic mean of the measurement results, with each measurement result should not exceed the permissible maximum deviations.