The tensile stress area A s corresponds to the reduced cross-sectional area inside the threaded part of the bolt. The interaction between shear and tension is expressed in EN1993-1-8 Table 3.4 according to the following linear relation:

v is a coefficient that takes values α v = 0.6 for bolt classes 4.6, 5.6, 8.8 or α v = 0.5 for bolt classes 4.8, 5.8, 6.8 and 10.9. When the shear plane passes through the unthreaded part of the bolt α v = 0.6. Depending on size, they have a proof load of 580-600 MPa, minimum yield strength of 640-660 MPa, and a minimum tensile strength of 800-830 MPa. Class 8.8 bolts come in all sizes ranging up to 72 mm. For full table with more Property Classes - rotate the screen! Metric Bolts - Fine Threads -Proof Loads Thread where e 1 is the distance between the center of the end bolt and the end of the plate measured parallel to the load direction, p 1 is the distance between the centers of neighboring bolts measured parallel to the load direction, and d 0 is the diameter of the bolt hole. For typical coarse pitch thread bolts the standard sizes are: M3, M3.5, M4, M5, M6, M7, M8, M10, M12, M14, M16, M18, M20, M22, M24, M27, M30, M33, M36, M39.

They are often used to secure engines and drives, alongside a host of other demanding applications. The first number of the bolt class corresponds to the ultimate strength e.g. 400 MPa for classes 4.x, 500 MPa for classes 5.x, 600 MPa for classes 6.x, 800 MPa for classes 8.x, and 1000 MPa for classes 10.x. In general the stress area of fine pitch thread bolts passing through the threaded part is larger as compared to the coarse pitch thread bolts. The standarized properties of metric bolts are specified in the international standard ISO 898-1:2009 'Mechanical properties of fasteners made of carbon steel and alloy steel - Part 1: Bolts, screws and studs with specified property classes - Coarse thread and fine pitch thread'. Ultimate Tensile and Proof loads for metric bolts according ISO 898-1 "Mechanical properties of fasteners made of carbon steel and alloy steel - Part 1: Bolts, screws and studs with specified property classes — Coarse thread and fine pitch thread".

Therefore, based on the equations above, the bearing resistance of the bolt F b,Rd is not affected by the distances e 1, p 1, e 2, p 2 when the following conditions are satisfied: For full table with more Property Classes - rotate the screen! Metric Bolts - Coarse Threads - Minimum Ultimate Tensile Loads Thread They are designated as above also including the pitch of thread in mm e.g. M8 × 1, M14 × 1.5, M27 × 2 etc. We hope these metric bolt torque charts have helped you discover the correct tightening torque for the bolts you use.According to EN1993-1-8 Table 3.4 the shear strength of the bolt may be based on the tensile stress area. The width of the hexagon nuts across flats s is specified in ISO 898-2 Table A.1 for bolt sizes M5 to M39. For full table with more Property Classes - rotate the screen! Metric Bolts - Coarse Threads - Proof Loads Thread By approximately ignoring the corner rounding for a perfect hexagon the relation of the distance across points s' and the distance across flats s is s' = s / cos(30°) = 1.1547⋅ s. For bolts with cut threads where the threads do not comply with EN 1090 the relevant resistances should be multiplied by a factor of 0.85 according to EN1993-1-8 § 3.6.1(3).

According to EN1993-1-8 § 3.6.1(4) the design shear resistance F v,Rd should only be used where the bolts are used in holes with nominal clearances not exceeding those for normal holes as specified in EN 1090-2 'Requirements for the execution of steel structures'. Proof load is defined as the maximum tensile force that can be applied to a bolt that will not result in plastic deformation. A material must remain in its elastic region when loaded up to its proof load typically between 85-95% of the yield strength. Acceptable clamp load is typically 75% of proof load.The nominal gross area A g corresponds to the cross-sectional area of the unthreaded part of the bolt: For preloaded bolted connections which are slip-resistant at the Serviceability Limit State or the Ultimate Limit State the corresponding shear load F v,Ed should not exceed the design slip resistance as specified in EN1993-1-8 §3.9 and Table 3.2. Only bolt assemblies of classes 8.8 and 10.9 may be used as preloaded bolts. The punching resistance of the bolt B p,Rd should be verified against the applied tensile load F t,Ed in accordance with EN1993-1-8 Table 3.4:

Refer to the charts below, which show the ideal tightening torque for each bolt grade for a variety of sizes. They have a proof load of 970 MPa, minimum yield strength of 1100 MPa, and a minimum tensile strength of 1220 MPa. Class 12.9 bolts come in sizes ranging from 1.6 mm to 100 mm. The resulting hole diameter d 0 for each type of hole (normal, oversize, short slotted, long slotted) is determined by adding the nominal clearance given in EN 1090-2 Table 11 to the nominal diameter d of the bolt. For full table with more Property Classes - rotate the screen! Metric Bolts - Fine Threads - Minimum Ultimate Tensile Loads Thread

The design shear resistance of bolts F v,Rd as given in EN1993-1-8 Table 3.4 is only valid when the bolt is used in holes with nominal clearance not exceeding the values given in the standard EN 1090-2 'Requirements for the execution of steel structures', as specified in EN1993-1-8 §3.6.1(4). They are made of quenched and tempered medium carbon steel and can be plated with a variety of materials, most commonly zinc.