ISO/TC 2/SC 12 - Fasteners with metric internal thread

ISO 2320:2015 specifies the functional properties for prevailing torque steel nuts when tested at an ambient temperature range of +10 °C to +35 °C. It includes a combined test method to determine the prevailing torque properties and the torque/clamp force properties at the same time. It applies to prevailing torque all metal type nuts and prevailing torque non-metallic insert type nuts: - with triangular ISO thread in accordance with ISO 68‑1; - with diameter/pitch combination in accordance with ISO 261 and ISO 262; - with coarse pitch thread M5 to M39 or with fine pitch thread M8 × 1 to M39 × 3; - with thread tolerances in accordance with ISO 965-2; - with mechanical properties in accordance with ISO 898‑2; Prevailing torque values specified in this standard are based on laboratory test conditions. NOTE 1 Actual prevailing torques in practical application can vary. NOTE 2 All metal type nuts conforming to the requirements of this International Standard are used in applications ranging from −50 °C to +150 °C. NOTE 3 Non-metallic insert type nuts conforming to the requirements of this International Standard are used in applications ranging from −50 °C to +120 °C. WARNING ? Temperatures outside the ambient temperature range can influence the functional properties (torque/clamp force and prevailing torque properties), see Annex A.

ISO 21670:2014 specifies characteristics for hexagon weld nuts with flange, with sizes M5 to M16 (coarse thread) or d = 8 mm to 16 mm (fine pitch thread), of product grade A. Weld nuts conforming to ISO 21670:2014 are suitable for use with bolts of property classes up to 10.9 according to ISO 898‑1.

ISO 4035:2012 specifies the characteristics of chamfered hexagon thin nuts (style 0), with threads from M1,6 up to and including M64, with product grade A for threads of diameter less than or equal to M16 and product grade B for threads of diameter greater than M16.

ISO 8675:2012 specifies the characteristics of chamfered hexagon thin nuts (style 0), with metric fine pitch thread, with nominal thread diameters from 8 mm up to and including 64 mm, with product grade A for sizes D ≤ 16 mm and product grade B for sizes D > 16 mm.

ISO 7719:2012 specifies the characteristics of prevailing torque type all-metal hexagon regular nuts with threads from M5 up to and including M36, in product grade A for threads up to and including M16 and product grade B for threads above M16, and with property classes 5, 8 and 10.

ISO 10511:2012 specifies the characteristics of prevailing torque type hexagon thin nuts (with non-metallic insert) with thread from M3 up to and including M36, in product grade A for threads up to and including M16 and product grade B for threads above M16, and with property classes 04 and 05.

ISO 10512:2012 specifies the characteristics of prevailing torque type hexagon regular nuts (with non-metallic insert) with metric fine pitch thread with nominal thread diameters, D, from 8 mm up to and including 36 mm, in product grade A for diamter sizes up to and including 16 mm and product grade B for diameter sizes above 16 mm, and with property classes 6, 8 and 10.

ISO 7040:2012 specifies the characteristics of prevailing torque type hexagon regular nuts (with non-metallic insert) with threads from M3 up to and including M36, in product grade A for threads up to and including M16 and product grade B for threads above M16, and with property classes 5, 8 and 10.

ISO 8674:2012 specifies the characteristics of hexagon high nuts (style 2) with metric fine pitch thread, with nominal thread diameters from 8 mm up to and including 36 mm, with product grade A for sizes D ≤ 16 mm and product grade B for sizes D > 16 mm. Coarse thread hexagon nuts, style 2, according to ISO 4033 are intended to be the first choice.

ISO 8673:2012 specifies the geometry of hexagon nuts with nominal thread diameter from 8 mm up to and including 64 mm and the mechanical properties of hexagon regular nuts (style 1) with metric fine pitch thread in product grade A for nominal thread diameters 8 mm less than or equal to D less than or equal to 16 mm and in product grade B for nominal diameters 16 mm less than D less than or equal to 39 mm.

ISO 7042:2012 specifies the characteristics of prevailing torque type all-metal hexagon high nuts with threads from M5 up to and including M36, in product grade A for threads up to and including M16 and product grade B for threads above M16, and with property classes 5, 8, 10 and 12.

ISO 10513:2012 specifies the characteristics of prevailing torque type all-metal hexagon high nuts with metric fine pitch thread with nominal thread diameters, D, from 8 mm up to and including 36 mm, in product grade A for diameter sizes up to and including 16 mm and product grade B for diameter sizes above 16 mm, and with property classes 8, 10 and 12.

ISO 4033:2012 specifies the characteristics of hexagon high nuts (style 2), with threads from M5 up to and including M36, with product grade A for threads of diameter less than or equal to M16 and product grade B for threads of diameter greater than M16.

ISO 4032:2012 specifies the characteristics of hexagon regular nuts (style 1), with threads from M1,6 up to and including M64, with product grade A for threads of diameter less than or equal to M16 and product grade B for threads of diameter greater than M16.

ISO 10663:2012 specifies the characteristics of hexagon nuts with flange (style 2), and metric fine pitch thread with nominal thread diameters, D, from 8 mm to 20 mm, in product grade A for D less than or equal to 16 mm and product grade B for D greater than 16 mm.

ISO 7043:2012 specifies the characteristics of prevailing torque type hexagon nuts with flange (with non-metallic insert), of style 2, with threads from M5 to M20 inclusive, in product grade A for threads up to and including M16 and product grade B for threads above M16, and with property classes 8, 9 and 10.

ISO 12126:2012 specifies the characteristics of prevailing torque type all metal hexagon nuts with flange (style 2), and metric fine pitch thread with nominal thread diameters from 8 mm up to and including 20 mm, in product grade A for diameter sizes less than or equal to 16 mm and product grade B for diameter sizes greater than 16 mm, and with property classes 6, 8 and 10.

ISO 4161:2012 specifies the characteristics of hexagon nuts with flange (style 2), with metric coarse threads from M5 to M20 inclusive, of product grade A for threads up to and including M16 and product grade B for threads above M16.

ISO 12125:2012 specifies the characteristics of prevailing torque type all metal hexagon nuts with flange (with non-metallic insert) of style 2, with metric fine pitch thread with nominal thread diameters from 8 mm up to and including 20 mm, in product grade A for diameter sizes less than or equal to 16 mm and product grade B for diameter sizes greater than 16 mm, and with property classes 6, 8 and 10.

ISO 7044:2012 specifies the characteristics of prevailing torque type all-metal hexagon nuts with flange (style 2) and threads M5 to M20 inclusive, in product grade A for threads up to and including M16 and product grade B for threads above M16, and with property classes 8, 9, 10 and 12.

ISO 7720:2012 specifies the characteristics of prevailing torque type all-metal hexagon nuts, of style 2, with threads from M5 up to and including M36, in product grade A for threads up to and including M16, and product grade B for threads over M16, and with property class 9.

ISO 7041:2012 specifies the characteristics of prevailing torque type hexagon nuts (with non-metallic insert), style 2, with threads from M5 up to and including M36, in product grade A for threads up to and including M16, and product grade B for threads above M16, and with property classes 9 and 12.

This Technical Report gives information concerning the design criteria for nuts specified in ISO 898-2 so that, under static tensile overload, the stripping fracture mode is prevented. The design criteria are also applicable to non-standardized nuts or internally threaded elements with ISO metric screw threads (in accordance with ISO 68-1) mating with bolts. However, dimensional factors such as the width across flats or other features related to rigidity of nuts, and thread tolerances can affect the load ability of the individual bolt and nut assemblies. Therefore, it is intended that verification tests be carried out. NOTE The terms "bolt" and "nut" are used as the general terms for externally and internally threaded fasteners, respectively.

This part of ISO 898 specifies mechanical and physical properties of nuts with coarse thread and fine pitch thread made of carbon steel and alloy steel when tested at an ambient temperature range of 10 °C to 35 °C. Nuts conforming to the requirements of this part of ISO 898 are evaluated at that ambient temperature range. It is possible that they do not retain the specified mechanical and physical properties at elevated and/or lower temperatures. NOTE 1 Nuts conforming to the requirements of this part of ISO 898 have been used in applications ranging from ?50 °C to +150 °C. It is the responsibility of users to consult an experienced fastener materials expert for temperatures outside the range of ?50 °C to +150 °C and up to a maximum temperature of +300°C to determine appropriate choices for a given application. NOTE 2 Information for the selection and application of steels for use at lower and elevated temperatures is given for instance in EN 10269, ASTM F2281 and in ASTM A320/A320M. This part of ISO 898 is applicable to nuts: a) made of carbon steel or alloy steel; b) with coarse thread M5 ≤ D ≤ M39, and fine pitch thread M8×1 ≤ D ≤ M39×3; c) with triangular ISO metric thread according to ISO 68-1; d) with diameter/pitch combinations according to ISO 261 and ISO 262; e) with specified property classes, including proof load; f) with different nut styles: thin nuts, regular nuts and high nuts; g) with minimum height m ≥ 0,45D; h) with a minimum outside diameter or width across flats s ≥ 1,45D (see Annex A); i) able to mate with bolts, screws and studs with property classes according to ISO 898-1. For hot dip galvanized nuts, see ISO 10684. This part of ISO 898 does not specify requirements for properties such as: — prevailing torque properties (see ISO 2320); — torque/clamp force properties (see ISO 16047 for test method); — weldability; — corrosion resistance.

ISO 4036:2012 specifies the characteristics of unchamfered hexagon thin nuts (style 0), with threads from M1,6 up to and including M10 and product grade B.

ISO 4034:2012 specifies the characteristics of hexagon regular nuts (style 1) with threads from M5 up to and including M64 and product grade C.

ISO 2320:2008 specifies the mechanical and performance properties for prevailing torque type steel nuts when tested at an ambient temperature range of +10 °C to +35 °C. It includes a single test to determine the prevailing torque properties (performance properties) and/or the torque/clamp force properties. ISO 2320:2008 applies to prevailing torque all metal type nuts and prevailing torque non-metallic insert type nuts: a) with triangular ISO thread according to ISO 68-1; b) with diameter/pitch combination according to ISO 261 and ISO 262; c) with coarse pitch thread M3 to M39 and mechanical properties according to ISO 898-2; d) with fine pitch thread M8×1 to M39×3 and mechanical properties according to ISO 898-6; e) within the temperature range of -50 °C to +150 °C for prevailing torque all metal type nuts; f) within the temperature range of -50 °C to +120 °C for prevailing torque non-metallic insert type nuts. ISO 2320:2008 does not apply: 1) to nuts of type e), outside the range -50 °C to +150 °C for prevailing torque all metal type nuts, when it is necessary to consult an experienced fastener materials expert to determine appropriate choices for a given application; 2) to nuts of type f), when use at or near the temperature limits can reduce the prevailing torque capability of prevailing torque non-metallic insert type nuts and can require the use of an adequate non-metallic material — it is necessary to consult an experienced fastener materials expert for temperatures outside the range -50 °C to +120 °C for prevailing torque non-metallic insert type nuts to determine appropriate choices for a given application.

ISO 21670:2003 specifies characteristics for hexagon weld nuts with flange, with sizes M5 to M16 (coarse thread) and M12 to M16 (fine thread), of product grade A. Weld nuts conforming to this International Standard are suitable for use with bolts of property classes up to 10.9 in accordance with ISO 898-1.

ISO 7041:2002 specifies the characteristics of prevailing torque type hexagon nuts (with non-metallic insert), style 2, with threads from M5 up to and including M36, in product grade A for threads up to and including M16 and product grade B for threads above M16, and with property classes 9 and 12.