Standard Profile of Screw Threads // Standard form of Screw Thread // Standard Thread Size //

Standard Profile or Form of Screw Threads 
This post deals with standard profile or form of a screw thread such as triangular or V thread and square thread.
The profile or form is the cross sectional shape of a thread.
It may be square, triangular, trapezoidal etc.

The common and basic screw thread profiles are triangular or V thread and square thread.
Triangular or V thread
This type of thread as triangular or V cross section.
All V threads have inclined flanks which make an angle between them.
In practical, a clearance must be provided between the external and internal threads.
These V threads are used to tighten two parts together in bolts and nuts, studs and nuts, etc.
To ensure the interchangeability between the bolts and nuts the same nominal diameter form is used.
These forms or profiles are called as standardized V thread profile.
The common examples are BSW thread, metric thread etc.
Square Thread
This type of thread as the square cross section.
The sides of the flanks of the square threads are vertical and parallel.
These type of threads are used in power transmission, screw jacks etc.
The modified form of the square thread is Knuckle thread.

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