Swaging is a metalworking process that forms and reduces the diameter of wire, rod, or tube. It can also add points or tapered ends to a cylindrical workpiece.
Rotary swaging machine have two or four dies that separate and close up to 2,000 times a minute. They have a spindle that looks like a cage containing rollers, which the dies ride as they cross each other.
The Basics
Swaging is a forging process that manipulates the size and shape of workpieces through compressive forces. It can be done hot or cold, but is generally performed cold to prevent hardening of the material.
Tube swaging shapes tubular metals into a desired shape. This is commonly used to form a wide range of products for the military, automotive, medical and commercial industries. Swaging also creates sealed joints, reducing the risk of wear and leaks.
To swage a wire or pipe, the end is inserted into the die. Then the tool is pushed down over the pintail, which is an additional portion of collar material protruding beyond the collar. The swaging tool applies a compression force against the pintail, forcing it into the grooves of the harder collar material. The result is a swage that’s more secure than a pop rivet. Swaging is much more precise than crimping, allowing the user to precisely control wall thickness.
The Die
A swaging machine uses two dies to hammer a rod or workpiece into a smaller diameter. The dies can be either stationary or rotary and hit the workpiece at a rate of about 10 – 20 strokes per second. This allows for more control of the wall thickness than a traditional forge could provide.
The lower half of the die is machined to conform with the shape that is needed for swaging, while the upper part supports different punches that perform various functions. These include the blanking punch that can form a profiled slug or cut a finished piece from a raw material. A piercing punch can also be used to create an internal or external thread.
Nitrogen, coil or neoprene springs can be attached to the lower half of the die to apply holding pressure and strip a finished piece from the tooling. This enables the operator to save time and money on labor costs by not having to continually handle the part in between swaging cycles.
The Spindle
Swaging machines work by using two or four split dies that separate and close up to several times a minute. They are mounted on the machine’s spindle which is rotated by a motor. The spindle is inside a cage which contains rollers (looks like a roller bearing). As the spindle turns the dies are pushed out to ride on the rollers. The rollers push the dies together because of their larger size.
This action causes radial blows to the metal which reduces the diameter of the rod or tube by forcing it into a confining die of specific dimensions. This process is referred to as swaging, and it is a common form of metal forming.
Swaging is a fast and economical method of forming parts. It is also very flexible and can accommodate many different shapes. In fact, if you have ever looked at the legs of a piece of furniture made from metal tubing, you will notice that they are swaged to create their desired shape.
The Cage
Swaging machines come in various sizes based on the type of work being performed. For example, smaller hydraulic swagers can be used to secure termination and joint fittings on wire ropes by deforming a ferrule or lug onto the end of a cable or core.
The larger rotary swager can use two or four split dies that separate and close up to 2,000 times a minute. They are mounted on the machine’s spindle which is located inside a cage containing rollers (looks like a roller bearing).
As the cage spins the dies slide out to ride on the rollers by centrifugal force. This allows the hammering to happen in a large area while still maintaining a high degree of accuracy and precision. The cage also limits the amount of hammering force applied to the workpiece to prevent it from damage or deformation. The head ring is made of heavy, hardened forge bearing steel heavily press-fitted into the swager frame to support the machine’s weight.