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. The second number corresponds to the ratio of yield strength to ultimate strength e.g. 60% for class 4.6 leading to a yield strength of 0.60 × 400 MPa = 240 MPa. The tensile stress area A s corresponds to the reduced cross-sectional area inside the threaded part of the bolt. Identify the class by the embossed number on the head, then find the size of your bolt in the chart. The ideal tightening torque can be found listed in two columns to the right.

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". Minimum end distance, edge distance, and spacing for bolt fasteners according to EN1993-1-8 Table 3.3 (rounded up to nearest mm) 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.

Refer to the charts below, which show the ideal tightening torque for each bolt grade for a variety of sizes.

For full table with more Property Classes - rotate the screen! Metric Bolts - Fine Threads - Minimum Ultimate Tensile Loads ThreadPitch is the distance from the crest of one thread to the next or the distance from one thread groove to the next, measured from crest to crest. Pitch is also described as the number of threads per inch. The diameter equal to the external diameter of the threads or the overall diameter of the part. (Nominal diameter is more of a label than a size. For example, a bolt and nut may be described as being ½” diameter. But neither the external threads of the bolt nor the internal threads of the nut are exactly .500 in diameter. In fact, the bolt diameter is a little smaller and the nut diameter a little larger. But it is easier to specify the components by a single size designation since the bolt and nut are mating components.) For full table with more Property Classes - rotate the screen! Metric Bolts - Fine Threads -Proof Loads Thread where e 2 is the distance between the center of the edge bolt and the end of the plate measured perpendicular to the load transfer direction, p 2 is the distance between the centers of neighboring bolts measured perpendicular to the load transfer direction, and d 0 is the diameter of the bolt hole. According to EN1993-1-8 Table 3.4 the bearing resistance F b,Rd of the bolt is not affected by the spacing p 1, p 2 and edge distances e 1, e 2 provided that the following limits are observed: e 1≥ 3.0 d 0, e 2≥ 1.5 d 0, p 1≥ 3.75 d 0, p 2≥ 3.0 d 0.