ISO 7500-1:2015 pdf free
ISO 7500-1:2015 pdf free.Metallic materials一Calibration and verification of static uniaxial testing machines
Mount tension force-proving instruments in the machine in such a way as to minimize any effects of bending (see ISO 376). For the alignment of a force-proving instrument in the compression mode, mount a platen with a ball nut on the instrument if the machine does not have an incorporated ball cup.
For calibration of tension and compression modes on testing systems that do not use compression platens for testing, the force proving device may be attached to the testing machine with threaded studs. In this case, the force proving instrument shall have been calibrated in a similar fashion (i.e.with threaded studs) and rotation of the force-proving instrument through an angle of 120° is required between each series of measurements during the calibration of the testing machine.
If the machine has two work areas with a common force application and indicating device, one calibration could be performed, so that e.g. compression in the upper work area equals tension in the lower work area, and vice versa. The certificate should carry an appropriate comment.
The calibration shall be carried out at an ambient temperature of between 10 °C and 35 °C. The temperature at which the calibration is carried out shall be noted in the verification report.
A sufficient period of time shall be provided to allow the force-proving instrument to reach a stable temperature. The temperature of the force-proving instrument shall not change by more than 2°C from the beginning to the end of each calibration run. If necessary, temperature corrections shall be applied
to the readings (see ISO 376).
Immediately prior to the calibration procedure, the force-proving instrument, in position in the machine, shall be preloaded at least three times between zero and the maximum force to be measured.
For testing machines with auto-ranging indicators, at least two force steps shall be applied on each part of the range where the resolution does not change.ISO 7500-1 pdf download.
