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Mechanical Properties of Steel Fasteners – Bolts, Screws and Studs

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Mechanical Properties of Steel Fasteners – Bolts, Screws and Studs TECHNICAL INFORMATION Contents Page Contents................................................................................................................................................15-0-1 & 2 Foreword..............................................................................................................................................15-1-1 Mechanical properties of steel fasteners – bolts, screws and studs ....................................................................................................................... 15- 5- 1 – bolts and screws M 1 to M 10 (breaking torques) .............................................................................. 15- 5- 2 – nuts - general explanation .......................................................................................................................... 15- 5- 3 - “DIN” nuts ......................................................................................................................................... 15- 5- 4 - “ISO” nuts with metric (ISO) screw thread with coarse pitch ............................................................ 15- 5- 5 - “ISO” nuts with metric (ISO) screw thread with fine pitch ................................................................. 15- 5- 6 & 7 - nuts classified according to hardness ............................................................................................... 15- 5- 8 Material properties of steel fasteners – steels ................................................................................................................................................... 15-10- 1 & 2 – heat treatments ................................................................................................................................... 15-10- 3 & 4 – chemical composition of bolts, screws and studs ............................................................................... 15-10- 5 – chemical composition of nuts .............................................................................................................. 15-10- 6 Screw threads – metric (ISO) screw thread with coarse pitch - M ................................................................................ 15-15- 1 – metric (ISO) screw thread with fine pitch - MF .................................................................................... 15-15- 2 – screw thread: fine versus coarse thread ............................................................................................. 15-15- 3 – metric screw thread with tolerance Sk6 for studs DIN 939 ................................................................ 15-15- 4 – metric screw thread with enlarged clearance for double end studs with reduced shank DIN 2510 .... 15-15- 4 – metric (ISO) trapezoidal thread - Tr for threaded rods and nuts ......................................................... 15-15- 5 – unified (ISO) thread - UNC, UNF and 8 UN ........................................................................................ 15-15- 6 – unified number threads - UNC and UNF ............................................................................................. 15-15- 7 – BA - (British Association) thread ......................................................................................................... 15-15- 7 – whitworth thread - BSW and BSF ....................................................................................................... 15-15- 8 – tapping screw thread - ST for tapping screws and drilling screws ...................................................... 15-15- 9 – wood screw thread for wood screws ................................................................................................... 15-15- 9 – metric-fine tapered external screw thread for pipe plugs DIN 906 ...................................................... 15-15-10 – whitworth tapered external screw thread for pipe plugs DIN 906 ....................................................... 15-15-10 – pipe threads - G, parallel, non pressure – tight ................................................................................... 15-15-11 Basic standards – core holes for tapping screws ............................................................................................................. 15-20- 1 to 4 – core holes for thread rolling screws in metals (Taptite) ...................................................................... 15-20- 5 – core holes for thread rolling screws in plastics (Plastite) ..................................................................... 15-20- 6 – clearance holes for bolts and screws .................................................................................................. 15-20- 7 – thread ends and length of projection of bolt ends ............................................................................... 15-20- 8 – run-out and undercut of screw thread ................................................................................................. 15-20- 9 – tolerance grades and tolerance fields (ISO) ....................................................................................... 15-20-10 – drill sizes for tapping of screw thread .................................................................................................. 15-20-11 – new widths across flats according to ISO ........................................................................................... 15-20-12 Surface coatings – electroplated coatings .......................................................................................................................... 15-25- 1 & 2 – hot dip galvanizing ............................................................................................................................... 15-25- 3 to 5 All technical specifications and data have been prepared most carefully and accurately using our best knowledge of state-of-the-art technics; however we shall not be held responsible for any legal problems or any other problems arising from the use of this information. 15 © COPYRIGHT FABORY 15-0-1 15 TECHNICAL INFORMATION Contents Page Inspection specifications – inspection documents 15-31- 1 to 4 Stainless steel – material properties of the steel grades A 1, A 2 and A 4 15-40- 1 & 2 – mechanical properties of the property classes 50, 70 and 80 15-40- 3 – guidelines for assembling - general 15-40- 4 - pre-loads and tightening torques 15-40- 5 Brass, Copper and Kuprodur 15-45- 1 & 2 Aluminium 15-50- 1 & 2 Plastics 15-55- 1 & 2 Tables – SI-units and conversion factors 15-60- 1 – conversion from inch to decimal inch to millimeter 15-60- 2 – conversion of tensile strength, Vickers-, Brinell- en Rockwell hardnesses 15-60- 3 – contact and chemical corrosion 15-60- 4 – surface roughness 15-60- 5 Standardization – introduction 15-65- 1 – index DIN-ISO standards 15-65- 2 to 8 – index ISO-DIN-ANSI standards 15-65- 9 & 10 Professional literature on fasteners technology 15-70- 1 & 2 All technical specifications and data have been prepared most carefully and accurately using our best knowledge of state-of-the-art technics; however we shall not be held responsible for any legal problems or any other problems arising from the use of this information. 15 © COPYRIGHT FABORY 15-0-2 FOREWORD Mechanical fasteners - bolts, screws, nuts etc. - are important technical construction parts. There is a clear trend towards: higher mechanical properties, stainless steel materials, corrosion-resistant surface coatings, special fastening systems with adequate assembling tools, fully automatic and robotized feeding and screwing equipment, increasing demand for higher quality and certification. Mechanical fastening is becoming a more and more advanced field of professional skill and knowledge. FABORY - a guarantee for quality It is not suprising that there is an increasing need for the advice of a technical expert and that in some companies, even in the early stages of development and design, the professional fastener engineer becomes involved in a new project so as to realize optimal construction. FABORY - a guarantee for quality We feel it as our task to compile the most relevant technical information on fasteners and screw threads in this practical reference guide for design, development, maintenance, purchasing, quality control, technical institutes etc. All technical information is of a general nature, is mainly based on the German DIN-, the European EN- and the international ISO- standards and is of importance for the construction, calculation and testing of bolted joints. For specific product information and non-standardized fasteners we refer to the various brochures of our documentation service. This reference handbook will regularly be kept up-to-date and will be extended to include new topics of general interest, as shown by the queries our Technological Department receives. FABORY - a guarantee for quality – the continuous increase of new fasteners and fastening systems – the regular adaptation of existing standards to the modern level of technics – the transition from national standards to the international ISO-standards and the European EN-standards do not make it simple for the user of fasteners to get the most recent and relevant information at the right time and to make (the right) use of it. With this new issue of “Fasteners Technology” we aim to meet the urgent need for professional information. FABORY - a guarantee for quality We appreciate any constructive criticism and comments you may wish to contribute. 15 ©
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