BS ISO 1711-2:2019 pdf free.Assembly tools for screws and nuts一Technical specifications.
4.3 Materials Sockets, driving squares, and all accessories shall be manufactured from steel.  The chemical composition and heat treatment shall be to produce tools conforming to requirements specified hereinafter. 4.4 Hardness testing The hardness test shall be carried out in accordance with ISO 6508-1.  Sockets and attachments shall be hardened and tempered to Rockwell hardness values given in Table 2. 5 Torque testing 5.1 Method The minimum test torsion torque values to be applied are given in Table 3. The socket shall be fully engaged in a hexagon test mandrel as shown in Figure 1. The height, h, and the width across corners, emma of the mandrel are specified in Table 3. The angle of the chamfer a shall be between 15° and 300. Smoothly apply the load until the minimum testing torque as given in Table 3 is reached. The nominal across-flats dimension of the test mandrel shall be equal to the nominal dimension, s, with a tolerance of h8. The mandrel shall be hardened to not less than hardness 55 HRC. A device in which the mandrel can be rotated at a certain torque determined with an accuracy of ±2,5 % can also be used for this test. Following the application of the minimum test torsion torque, any possible damage or deformation shall not affect the usability of the tool.5.2 Test of machine-operated square drive sockets A square mandrel of hardness not less than 55 HRC shall be used for driving the socket for nominal width across flats 22 mm and smaller. A square mandrel of hardness not less than 50 HRC shall be used for driving the socket for nominal width across flats 24 mm and larger. The nominal width across-flats dimension of this mandrel shall be equal to the maximum dimension, with a tolerance of h8, of the corresponding square drive. The axis of the two mandrels and the axis of the socket shall remain coaxial during the test.BS ISO 1711-2 pdf download.