Thread Tapping – Issues & Solutions
Thread tapping is a process of creating a thread inside a hole so that a screw, bolt or other similar component can be fitted into the tapped hole. It is widely used in the manufacture of various components across industries. Thread tapping methodologies come into play while creating various types of threads, such as Unified National Coarse (UNC) threads, Unified National Fine (UNF) threads and others. Several techniques of thread tapping, such as hand tapping, bolt tapping, drill bit tapping, and machine tapping, are currently employed. Issues typically faced while tapping threads vary with the threads used. This paper will discuss some of the most common issues faced while using threads, as well as solutions for those issues.
One of the most common issues faced while tapping threads is thread stripping. This is when the thread tap does not properly engage in the material being used, leading to the threads being stripped and the thread tap stuck in the material. This typically happens when the wrong type of thread tap is used for the material being tapped, or when the tap lacks the necessary clearance for the material being tapped. The solution for this issue is to ensure that the tap being used is the correct size and type for the material being tapped and to ensure that the tap has sufficient clearance for the material being tapped.
Another issue faced while tapping threads is inaccurate tapping. This occurs when the threads are not being tapped to the correct depth or the threads being tapped are not consistent in size. This issue can be attributed to many factors, such as incorrect tapping parameters, incorrect thread taps, incorrect drill bit sizes, and inaccurate machine tooling. The solution to this issue is to ensure that correct tapping parameters and drill bits sizes are used, and that the taps and other threading tools used are of the correct size and shape. Additionally, threading tools should be regularly inspected and maintained to ensure they are in the best working condition possible.
A further issue faced while tapping threads is galling, which is when metal is torn from the thread tap due to friction and high temperatures. This can occur when tapping soft metals, such as aluminum or brass, or when the thread taps are not lubricated correctly. The solution for this issue is to use lubricants that are specific for the application and to ensure that the threads are tapped at low speeds to reduce the friction between the tap and the material being tapped. Additionally, using the correct tap geometry and tap size can help reduce the risk of galling.
Finally, an issue faced while tapping threads is tapping a hole that is too deep. This can lead to the thread tap being damaged as it reaches the bottom of the hole. The solution for this issue is to make sure that a correct drill bit is used when creating the initial hole, and to ensure that the correct tapping parameters are used to make sure that the threads are not tapped beyond the desired depth.
In conclusion, the issues discussed in this paper are among the most common issues faced while tapping threads. It is important to ensure that the correct type of thread tap is used for the material being tapped, and to ensure that tapping parameters and drill bit sizes are correct. Additionally, lubricants specific for the application should be used, and machine tooling should be regularly checked and maintained. By following these guidelines, thread tapping can be done properly with minimal issues.
