A tapping machine is a specialized tool designed primarily to cut internal threads into pre-drilled holes in workpieces using standard taps.
What is a Tapping Machine?
A tapping machine, also known as a tapping press or tapping center, is a machine specifically built or adapted for the task of creating screw threads inside holes. While manual tapping is possible, tapping machines automate or assist the process, making it more accurate, efficient, and suitable for production environments.
The Core Function: Cutting Internal Threads
According to the reference, the fundamental way a tapping machine works is by being designed to operate a standard series of taps to cut internal threads into pre-drilled holes in workpieces.
Here's a breakdown of this function:
- Uses Standard Taps: The machine is built to utilize standard tapping tools, which are multi-point cutting tools shaped like screws, designed to cut the helical ridges inside a hole.
- Works on Pre-drilled Holes: The machine doesn't create the initial hole; it requires the holes to be already drilled to the correct size (the tap drill size) before it can perform the tapping operation.
- Cuts Internal Threads: Its main purpose is to form the spiral ridges on the inside surface of these pre-drilled holes. These internal threads allow screws or bolts to be fastened securely.
- Operates Taps: The machine operates the tap by rotating it and feeding it into the pre-drilled hole at the correct speed and depth, ensuring the threads are cut accurately and consistently.
The Tapping Process Simplified
While the specifics vary by machine type, the basic operation involves:
- Workpiece Placement: The workpiece with pre-drilled holes is secured on the machine's table or fixture.
- Tap Alignment: A tap of the desired size and thread type is mounted in the machine's spindle and aligned with a pre-drilled hole.
- Thread Cutting: The machine rotates the tap and feeds it into the hole. The cutting edges of the tap shave away material, forming the internal threads as the tap advances.
- Retraction: Once the desired thread depth is reached, the machine reverses the tap's rotation to back it out of the newly tapped hole without damaging the threads.
This automated or semi-automated process ensures precise control over tap speed, feed rate, and alignment, which is crucial for producing high-quality threads consistently, especially when dealing with multiple holes or hard materials.
