Surface Pressure Data

Surface pressure underneath head of hex cap screws DIN 931 / 933 (ISO 4014 / 4017) Hexagon nuts DIN 934 (ISO 4032)
Nominal DimensionWidth across flats (mm)Washer Face Diameter (mm)Clearance Hole (ISO 273)Bearing Surface (mm)   Stress Area (mm2)Surface  pressure underneath head N/mm2
8.810.912.9
M35.54.63.47.455.03307434520
M475.94.511.48.78352496596
M586.95.513.614.2484680799
M6108.96.62820.1332466559
M81311.694236.6406571686
M101614.61172.358375528633
M101715.61196.158282398477
M121816.613.573.284.3541760913
M121917.413.594.684.3419588706
M142119.615.5113115481676812
M142220.515.5141115385529650
M162422.517.5157157476669803
M182725.320188192484681816
M203028.222244245480672807
M22323024254303575807969
M223431.724337303433608730
M243633.626356353472663798
M27413830427459518728876
M304642.733576561467656788

 

Surface pressure underneath head of socket hex cap screws DIN 912 (ISO 4762)
Nominal DimensionWidth across flats (mm)Washer Face Diameter (mm)Clearance Hole (ISO 273)Bearing Surface (mm)Stress Area (mm)Surface  pressure underneath head N/mm2
8.810.912.9
M35.55.073.411.15.03209295353
M476.354.517.68.78228322386
M58.58.035.526.914.2245344413
M6109.386.634.920.1266374449
M81312.33955.836.6306430516
M101615.331189.558303427512
M121817.2313.59084.3440618742
M142120.1715.5131115415583700
M162423.1717.5181157476580696
M182725.8720211192431607727
M203028.8722274245427599719
M223331.8124342303427599719
M243634.8126421353399561675
M274038.6130464459476670608
M304543.6133638561422592712

The values for surface pressure are obtained with 90% utilisation of the screw yield point

Note: Due to the fact that fastening applications differ greatly, the above information is for guidance only and is correct to the best of our knowledge. The customer must satisfy themselves with the performance of the fastener and validity of the data. TR Fastenings will not be held responsible for any failure that may occur from the use of this information.