NF ISO 965-5, E03-057 (03/2025)

This part of ISO 965 specifies the deviations and limit dimensions of the flank and crown diameters of general purpose ISO metric internal threads, in accordance with ISO 262, of basic profile in accordance with ISO 68- 1. Internal threads conforming to this part of ISO 965 are intended to mate with external threads of maximum tolerance position h before hot-dip galvanizing. The limit dimensions, specified for the quality class adopted, are derived from the tolerances specified in ISO 965-1. The fundamental deviations of internal threads from tolerance position AZ were calculated according to the following formula: EIAZ = + (300 + 20P) Where EI is expressed in micrometers; P is expressed in millimeters. The fundamental deviations of internal threads from tolerance position AX were calculated according to the following formula: EIAX = + (220P - 20) Where EI is expressed in micrometers; P is expressed in millimeters. Products made with thread tolerances conforming to this part of ISO 965 may fail at proof loads when tested in accordance with ISO 898-2 without adaptation of other mechanical properties . Internal threads made with thread tolerances conforming to this part of ISO 965 should not be assembled with external threads having thread tolerances conforming to ISO 965-4, because such a combination creates significant risks of thread tearing. NOTE Internal threads of tolerance class 6AZ are mainly intended to be assembled with external threads spun after hot-dip galvanizing. Tolerance class 6AX internal threads are primarily intended to mate with non-centrifuged and coated hot-dip galvanized external threads.
(Automatic translation from French)