The design resistance of a group of fasteners may be taken as the sum of the design bearing resistances F b,Rd of the individual fasteners provided that the shear resistance F v,Rd of each individual fastener is greater than or equal to the design bearing resistance F b,Rd. Generally used in timber to timber and timber to metal construction, these bolts incorporate a square neck to grip the hole in the timber when fitting, and therefore negates the need for any drive recess to be included on top of the head. Westfield Fasteners Limited is a company registered in England and Wales with company number 07215583.

For this case elastic linear distribution of internal forces should be used as specified in EN1993-1-8 §3.UNBRAKO® branded and manufactured to be stronger than the other size for size high tensile versions. Compare the bolts you have with the diagrams below, then refer to the appropriate chart to see the ideal tightening torque.

the bearing resistance F b,Rd for bolts in holes other than normal should be multiplied by the following reduction factors: Oversized holes = 0. In addition for countersunk bolts the bearing resistance F b,Rd should be based on a plate thickness t equal to the depth of the connected plate minus half the depth of the countersinking. When the shear plane passes through the threaded part of the bolt A is equal to the tensile stress area of the bolt A s.that due to the nature of the surface finish on Unbrako products, some surface corrosion may be evident. M14 bzp hexagon head bolts are manufactured from steel and have a diameter of 14 mm, conform to DIN 931 spec, and have a partial thread.

where bolts transmitting load in shear and bearing pass through packing plates of total thickness t p greater than d / 3 the design shear resistance F v,Rd should be multiplied by the reduction factor β p specified in EN1993-1-8 equation 3. Otherwise the design resistance of a group of fasteners should be taken as the number of fasteners multiplied by the smallest design resistance of any of the individual fasteners as specified in EN1993-1-8 § 3.They are made of quenched and tempered medium carbon steel and can be plated with a variety of materials, most commonly zinc. If you might need to look up the ideal tightening torque for metric class bolts again, why not bookmark this page so that you can refer to it more easily in the future? Download the Metric Clearance Hole Chart to save the chart as a PDF – useful to print out to have next to your tools.