Many machines and fabrication projects depend on threaded bolts and nuts. Also, automotive, aerospace and marine applications often use threaded components and fasteners. Today’s threading operation includes rolled threads and cut threads. Both have advantages and disadvantages, and this information can help you make the right choice for your business.
Cut Threads
Cutting threads is one of the oldest and most dependable ways to make threads. Threads are sometimes cut manually with tap and die tools, but modern machining methods are faster. High-speed milling machines cut into metal parts while they remain stationary.
Turning machines also do thread cutting. By turning the workpiece against a cutting tool, it creates threads. The process is not the fastest, but it’s an exact threading operation.
Thread Rolling
In the rolling process, a thread die places pressure against the blank. As it rolls, the die digs into the metal to create threads. When this takes place at room temperature, it’s called cold threading. There are four basic methods for thread rolling:
Flat die
Two dies (cylindrical)
Three dies (cylindrical)
Planetary dies
Rolling takes less time to created threaded components. In fact, this method is commonly used for mass producing threaded fasteners like screws, nuts, and bolts.
Benefits of Cutting Threads
The thread cutting process is the most accurate method for threading. It creates a uniform piece in which a smooth shaft has the same diameter as the threads. However, this process requires more time than thread rolling, and the threading operation is more expensive. When you need precision threads, it’s the best option.
Thread Rolling Benefits
Rolling threads gives you many parts in a short time. The threading operation is perfect for non-precise threads. However, with bolts and nuts, it produces threads with larger diameters than the shafts.
