BOZONLI M18 Lengthen Hex Bolt - Fully Threaded Setscrew Stainless Steel Mechanical Bolts M18×30mm,1 pcs

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Bulgarian, Croatia, Cyprus, Estonia, Hungary, Latvia, Lithuania, Malta, Romania, Slovakia, Slovenia

Here’s a short list of standard spanner and allen key sizes that apply to the most commonly used metric nuts and bolts. Standard metric spanner and allen key sizes. Size Metric Threads are measured in Millimetres (mm) units and were developed to simplify the imperial systems. Europe moved to this system but the Americans choose Imperial as their default. A coarse thread has less helical coils per mm and a fine one has more. Coarse is used for heavier loads and fine is used for lighter loads prone to vibrations. Metric nuts and bolts are commonly referenced using ‘M’ sizes, for example: M3, M8, M12. But the size of a metric fastener is more accurately specified using diameter, pitch and length dimensions, in millimeters. For nuts the size dimensions used are simply diameter and pitch. 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.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. Austria, Azores, Czech Republic, Denmark, Finland, Greece, Italy, Madeira, Poland, Portugal, Spain, Sweden 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. 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'. Minimum and maximum spacing p 1, p 2 and edge distances e 1, e 2 for bolts are given in EN1993-1-8 Table 3.3. The minimum values are: e 1≥ 1.2 d 0, e 2≥ 1.2 d 0, p 1≥ 2.2 d 0, p 2≥ 2.4 d 0, where d 0 is the diameter of the hole, e 1, p 1 are measured parallel to the load transfer direction and e 2, p 2 are measured perpendicular to the load transfer direction.

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. Albania, Andorra, Belarus, Bosnia and Herzegonia, Ceuta, Faroe Island, Gibraltar, Greenland, Guernsey. Iceland, Jersey, Kosovo, Liechenstein, Macedonia, Moldova, Montenegro, Norway, Russia, San Marino, Serbia, Switzerland, Turkey, Ukraine The yield strength f yb and the ultimate tensile strength f ub for bolt classes 4.6, 4.8, 5.6, 5.8, 6.8, 8.8, and 10.9 are given in EN1993-1-8 Table 3.1. 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.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.

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: When it’s necessary to cut a thread then the hole size needs to be a smaller diameter to allow for the thread to be tapped. The necessary tapping hole size can be easily calculated by deducting the thread pitch from the metric bolt diameter. For example, an M8 bolt with a standard coarse thread pitch of 1.25mm would require a hole of 6.75mm diameter to be tapped. But if the M8 bolt had a fine pitch thread of 1mm then the diameter of the hole required for tapping would be 7mm.

As noted, the specification of metric bolts includes the definition of thread pitch, but if this is omitted then a coarse pitch is assumed. Metric fasteners are available with either coarse or fine thread pitches with some metric bolt sizes offering extra fine thread pitch options. It is worth noting that metric bolts with a coarse thread pitch have more threads per inch (they are more closely spaced) than comparable imperial bolts. List of common metric bolt sizes. Metric Coarse M2 is the partial safety factor for the resistance of bolts in accordance with EN1993-1-8 §2.2(2) Table 2.1 and the National Annex. The recommended value in EN1993-1-8 is γ M2 = 1.25. For full table with more Property Classes - rotate the screen! Metric Bolts - Coarse Threads - Proof Loads Thread 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'.