Proper preloading of a bolted connection is such a difficult task. Therefore, each with their specific pros and cons several different tightening methods was developed. So, various methods are preferred in different sectors or for certain applications.
One of the most essential problems with the use of bolted joints is the precision, with regard to accomplishing an accurate preload, of the bolt tightening method selected. Insufficient preload, caused by an incorrect tightening method, is a frequent cause of bolted joint failing. It is necessary for the Designer to appreciate the features and features of the primary methods employed to tighten bolts.
Below are the common 6 methods of the most essential bolt tightening methods. Note however that whatever method used to tighten a bolt, a degree of bolt preload scatter is to be expected.
To control the preload of a threaded fastener there are six primary methods used. Specifically:
1. Torque control tightening.
2. Angle control tightening.
3. Yield controlled tightening.
4. Bolt stretch method.
5. Heat tightening.
6. Use of tension indicating methods.
One of the biggest challenges when working with bolted joints is accomplishing a precise, precise preload. Inadequate preload is a common cause for bolted joint failing, which is why it’s so essential to use the appropriate bolt tightening methods.