What precautions should be taken when tapping during the installation of wire thread inserts?

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During the installation of wire thread inserts (threaded sleeves), the first step is tapping. So, how is tapping carried out during the installation of wire thread inserts (threaded sleeves)? What are the specific steps involved? China Steel Thread Insert Network answers your questions one by one. First, we need to understand that the precision of tapping determines the tolerance band of the final internal screw hole. Users should choose the appropriate tapping method and lubricant, and apply sufficient force when tapping blind holes to prevent the tap from breaking. We need to use tap bits specifically designed for screw sleeves of the appropriate specifications to tap the drilled holes. When new tap bits are first put into use, as well as when they are nearly worn out, thread plug gauges must be used to check the screw holes in order to determine whether the tap bits are still usable. It can be specifically divided into the following steps: (1) The opening of the bottom hole for the thread on the workpiece should be chamfered, and both ends of the through-thread should also be chamfered. (2) The workpiece clamping position must be correct; try to keep the centerline of the threaded hole in a horizontal or vertical position, so as to make it easier to determine whether the tap axis is perpendicular to the workpiece’s surface. (3) At the start of tapping, make sure to align the tap as accurately as possible, then apply pressure to it and turn the handwheel; after it has cut 1–2 turns, carefully check and adjust the position of the tap. Generally, when cutting 3–4 turns of thread, the tap’s position must be accurate. From now on, it is sufficient to turn the handwheel; no pressure should be applied to the tap any longer, otherwise the thread profile will be damaged. (4) When tapping, turn the twist drill 1/2–1 full turn at a time, then reverse it by about 1/2 turn to break up the chips and facilitate their removal, as well as to reduce the risk of the tap getting stuck due to debris sticking to the cutting edge. As long as you follow the steps above, threading with wire thread inserts will be a piece of cake for you.