Whenever a part or component needs to be threaded, using the right threading operation and the correct equipment is essential. Over time, and with the improvement both in the actual equipment as well as the use of CAD/CAM technology, threading can be very specifically controlled through modern lathes to create a perfect thread each and every time.
The reason something as simple as the threading is so important is that it provides for easier assembly of components and less waste. This cuts down both on the cost of labor, saved with efficient fabrication, as well as reducing the cost of the production due to wasted material that is incorrectly threaded.
Considerations
At first glance, it may seem that a threading operation would be very basic, and one that required little in the way of specialized equipment or experience on the part of the machine operator. However, there are several aspects to threading on a lathe can makes it more complex and difficult to plan for because of all the variable that have to be taken into considerations.
First, the cutting forces during threading are higher than with many types of turning operations. This is becoming more pronounced as the diameter of the rod or component being threaded becomes smaller.
There are also variations depending on the TPI or threads per inch required with the specific threading operation. The feed rate has to be set and maintained consistent throughout the process, and it is usually about 10 times higher than that of any other turning requirements.
Cutting
Another consideration with threading as opposed to other types of turning operations on a lathe is the cutting action. This has to be carefully controlled and there can be no shear, or the last few threads can be distorted. This results in unusable products or components that are impossible to use, creating additional waste and delays in production.
New technology in the CNC lathes used in any threading operation can help to maintain tools for much longer. Through using multi-tooth inserts clean, crisp threads can be cut into the material, as each tooth deepens the thread, limiting wear and tear.
However, it is essential for the operator of the equipment used in the threading operation to understand the potential drawbacks of each type of option. Factors such as chatter can ultimately create uneven surfaces on thin parts, and all of these things have to be taken into consideration when setting up the equipment and process.
