Threaded joints are defined as separable joints which are used to hold to machine parts together by means of threaded fastening such as bolt and nut.
Image source: NZDL
Above image shows a bolt joining two parts. In first case second part works as a nut and in second case a separate nut is provided to hold the parts together.
Features of threaded joints
From the above definition we can find some features of them and they are.
- They are detachable joints which means when required the joined machined parts can be dismantled without damaging any part.
- Threads are the basic element of these joints. They can be nut and bolt or screw and stud etc.
Advantages of threaded joints
They offer several advantages and some of them are.
- They are reliable
- Less force is required to tight a joint because of the mechanical advantage offered by spanner
- They have small overall dimensions and are compact in construction
- Threads have self-locking property hence they can be used in any position either vertical or horizontal
- Their manufacturing is simple hence they are cost effective
- Parts joined by them are easily detachable
- Wide variety of threaded fasteners are available in market with standardized dimensions
Disadvantages of threaded joints
They have some disadvantages too, and they are.
- Parts joined by threaded joints are vulnerable to failure due to stress concentration near the holes
- Due to time and labor taken in manual assembly the cost in tightening a screw can be up to six times the cost of screw itself
We hope now you understand threaded joints in a better way. If you still have some doubts please feel free to ask them through comments section.