BS 131-4:1972

Co-operating organizations
Foreword
Methods
1 Scope
2 Inspection of machine and its installation
3 Level
4 Bearings
5 Location of pendulum
6 Initial potential energy
7 Impact velocity
8 Centre of percussion
9 Test piece supports
10 Striker
11 Indicating equipment
12 Friction losses
13 Certificates of calibration and verification
Appendix
A Accuracy of gauges
Figures
1 Details of Izod machine
2 Details of Charpy machine
3 Dimensions for calculations

Inspection, calibration and verification of the machines in Parts 1, 2 and 3. Accuracy of gauges used in checking components, in an appendix.

1.1 This Part of this British Standard gives methods for the inspection, calibration and verification of Izod pendulum impact testing machines, and includes instructions for certificates of calibration and verification. The methods cover the following elements of the machine, which are illustrated in Figure 1:

1. machine framework (i.e. the structure supporting the pendulum, excluding only the foundation);
2. pendulum and striker;
3. test piece supports;
4. indicating equipment (e.g. scale and friction pointer).

1.2 In applying the methods all the absorbed energy indicated by the machine is attributed to the fracturing of the test piece.

NOTE It is known that energy is absorbed other than by fracturing the test piece. It is assumed that this energy is absorbed by items such as the test piece supports, the machine foundation and framework, the pendulum and striker, translation of the broken part of the test piece and drag of a partially broken test piece. This energy is not determined as suitable methods and apparatus have not yet been developed for measuring either its total or constituent parts.