Torque Conversion FactorsThe below formulas and information provide guidance on different conversion factors e.g. the effect of torque wrench extensions. Units to be converted S.I. Units Imperial Units Metric Units cN·m N·m ozf·in lbf·in lbf·ft Kgf·cm Kgf·m 1 cN·m = 1 0.01 1.416 0.088 0.007 ...
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Recommended Maximum Torque Values The information supplied here is intended to be an acceptable guide for normal conditions. For critical applications, further information and research will be necessary. The following basic assumptions have been made: a. Bolts are new, standard finish, uncoated and not lubricated (other than the normal protective oil film)b. The load will be 90% of the bolt yield strengthc. The coefficient of friction is 0.14d. The final tightening sequence is achieved...
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Tightening to YieldBolts tightened to yield provide consistently higher preloads from smaller diameter bolts. The reduced fastener stiffness reduces the fatigue loading to which the bolt is subjected under repeated external load reversals, e.g. cylinder heads and connecting rods. In theory, a bolt tightened to its yield point will provide the strongest and most fatigue-resistant joint possible, within the physical limitations of the bolt material and manufacturing process. The downside...
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Well done Arron & Joe! Last Thursday we attended the Engineering Trust Annual Apprentice Awards Evening 2019. Well done to Arron Moore who was nominated and runner up in the 3rd year apprentice nominations. Arron was nominated because he set out to achieve the highest results both at college and his work evidencing his company training plan and NVQ3 qualification. His assessor said ‘he must be one of the very few apprentices whom I’ve told to produce less deta...
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Friction in the Bolted JointWhen a threaded fastener is tightened, the induced tension results in friction under the head of the bolt and in the threads. It is generally accepted that as much as 50% of the applied torque is expended in overcoming friction between the bolt head and the abutting surface and another 30% to 40% is lost to friction in the threads. As little as 10% of the applied torque results in useful work to tension the bolt. Given that up to 90% of the applied torque w...
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What is Torque?Torque is any force or system of forces that tends to cause rotation about an axis. Measurement of TorqueImagine someone tightening a bolt using a socket attached to a meter (m) long bar. If they apply 10 kg of force (kgf) perpendicular to the bar they will produce a torque of 10 kgf·m at the axis (the centre of the bolt).However, under the S.I. system of measurement, force is expressed in Newtons (N) rather than kgf. The conversion between kgf and N is x 9.807 so the ...
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Our annual 2019 careers open evening was last Thursday. Despite the slightly lower numbers than usual, it was a highly successful evening. Over 50 guests came to see us which allowed Norbar staff to spend more quality time talking to parents, potential apprentices and employees about careers in engineering.More excitingly this year we had more females visit to talk to us; maybe there has been a turning point at last. Thank you to Chris and Rob of the Engineering Trust, our training provider who ...
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Reflecting on 2018 my first thought was “hard work, a year best left behind”. However, as I looked back through my notes I realised how wrong my first reflection was. True, we did have to work hard and there were some setbacks but actually there were some spectacular successes as well. This is how the year went. JanuaryWe hit the ground running with people travelling all over the world. Neill was in India for the official opening of the “Ian Brodey ...
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During October, Norbar held its 4th Rapid Continuous Improvement (RCI) workshop and the 3rd this year.5 new teams looking to improve 5 key processes: - Small Torque Wrench Assembly & Calibration Secondary Motion Assembly Speed Design Review Machine Shop Reorganisation Multiplier Surface finishing Each team of between 6-8 members included process operators (the experts), Engineers, guests from other processes and guests from Norbar and other Snap-on companies. We welcomed back...
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