ISO 4759 standard consists of the following parts, under the general title Tolerances forfasteners:
ISO 4759-1 Part 1: Bolts, screws, studs andnuts — Productgrades A, B andC
ISO 4759-3 Part 3: Plain washers forbolts, screws ans nuts — Productgrades A andC
ISO 4759-3 Part 2: Bolts, screws and nuts with thread diameters from 1 up to 3 mm and product grade F, for fine mechanics
ISO 4759-1 specifies a selection of tolerances for bolts, screws, studs and nuts with ISO metric threads and with product grades A, B and C and for tapping screws with product grade A.
The tolerances, except tolerances for threads, are selected from the system of limits and fits specified in ISO 286-1 and ISO 286-2. The tolerances for metric threads are taken from the series of tolerance classes specified in ISO 965-3. The tolerances for tapping screw threads are covered in ISO 1 478.
The tolerances of form and position are specified and indicated in accordance with ISO 1 1 01 , ISO 801 5 and ISO 2692.
The tolerances specified in this part of ISO 4759 apply to fasteners prior to coating unless otherwise specified. See also ISO 4042.
Deviations from the tolerances specified in this part of ISO 4759 are only permitted in product standards where there are valid technical reasons. In cases where there is a difference between the tolerance requirements in this part of ISO 4759 and the product standard, the product standard takes precedence.
Dimensions and tolerances given in this part of ISO 4759 are in millimetres.
ISO_4759_2_tolerance_fastener_standard
ISO_4759_3_tolerance_fastener_standard
