This site is operated by a business or businesses owned by Informa PLC and all copyright resides with them. Informa PLC’s registered office is 5 Howick Place, London SW1P 1WG. Registered in England and Wales. Number 8860726. Jointing is a basic function of engineering. For example, bolting two parts together can involve material properties and loading forces. Here, we will focus on preloading, shear, and tear-out in a bolted assembly. However, designers must consider multiple engineering principles including the internal and external loads discussed in a number of articles on Machine Design’s website. Engineers may have learned about these stresses in school, but one of the factors that complicate what might seem like a simple bolted joint is the clamping force, or preload. Calculating non-preloaded connections can use typical shear and bearing formulas explained later in this article. However, preload is often a factor in a joint’s fatigue life; it introduces tensile forces, and can promote creep. It is important to calculate the proper area. Depending on the design, a pin or bolted joint might share a load over multiple surfaces In the second image, the load will...