ASTM E4-09 pdf free download.Standard Practices for Force Verification of Testing Machines.
1.1 These practices cover procedures for the force verification, by means of standard calibration devices, of tension or compression, or both, static or quasi-static testing machines (which may. or may not, have force-indicating systems). These practices are not intended to be complete purchase specificalions for testing machines. Testing machines may he verified by one of the three following methods or combination thereof’:
1.1.1 Use of standard weights,
1.1.2 Usc of equal-arm balances and standard weights, or
1.1.3 Usc of elastic calibration devices.
NOTE 1—These practices do not cover the verification of all types of testing machines designed to measure forces, for example, the constant- rate-of-loading type which operates on the inclined-plane principle. This type of machine may be verified as directed in the applicable appendix of Specification D 76.
1.2 The procedures of 1.1.1-1 .1.3 apply to the verification of the force-indicating systems associated with the testing machine, such as a scale, dial, marked or unmarked recorder chart, digital display. etc. hi all cases the buyer/owner/user must designate the fo rc e- indicating system(s) to he verified and included in the report.
1.3 The values stated in inch-pound units are to he regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard.
1.3.1 Since conversion factors are not required in this practice, either inch-pound units. SI units, or metric values can be used as the standard.
1 .4 Forces indicated on displays/printouts of testing machine data systems—bc they instantaneous, delayed, stored, or retransmitted—which are verified with provisions of 1.1.1, 1.1.2, or 1.1.3, and are within the ± 1 % accuracy requirement, comply with Practices E 4.
3. lerminology
3. 1 Definitions:
3. 1 . 1 testing machine (force—measuring tvpe)—a mechanical device for applying a force to a specimen.
3. 1. 1 . 1 portable testing machine (force-measuring type)—a device specifically designed to he moved from place to place and for applying a force (load) to a specimen.
3.1.2 force—in the case of testing machines, a force measured in units such as pound-force, newton, or kilogram-force.
3. 1 .3. 1 Discussion—A testing machine is said to be accurate if the indicated force is within the specified permissible variation from the actual force. In these methods the word “accurate” applied to a testing machine is used without numerical values, for example, “An accurate testing machine was used for the investigation.” The accuracy of a testing machine should not be confused with sensitivity. For example, a testing machine might be very sensitive; that is, it might indicate quickly and definitely small changes in force, but nevertheless, be very inaccurate. On the other hand, the accuracy of the results is in general limited by the sensitivity.ASTM E4 pdf download.