Dissecting the Nut Factor

Archer, David
January 2009
Assembly;Jan2009, Vol. 52 Issue 1, p12
This article discusses the factors that cause the value of the nut factor to vary about 300 percent. As stated, the nut factor is not derived from engineering principles but is arrived at experimentally to make the equation valid. Published test procedures require tensioning a threaded fastener in a controlled manner, while monitoring both torque and tension. When competent testing of the actual components is practical, the short-term equation will give the most accurate torque-tension relationship.


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