Tube End Form Tooling Information
Tube end form tooling is made for tube end forming machines which manipulate the size and shape of tube ends for various applications.
The basic end forming methods are segmented tool sizing, ram forming, rotary forming, roll forming, and spinning. When selecting a tube end form tool it is important to consider what the formed tube needs to do, whether the project is a part of an assembly of parts, and if changes can be made to mating parts.
Also important to consider is if the tube material can accommodate the desired amount of deformation, and if so, what the best way to work with the material is in order to achieve the end form while maintaining the appropriate tolerances and cosmetic requirements.
There are several styles of tube ends available.
End reduction is a process that reduces the outside diameter (OD) of the tube. This is done so that the reduced end will fit into the inside diameter (ID) of the same tube.
End expansion is mainly performed using horizontal pneumatic and hydraulic end forming equipment adapted by technicians to suit application requirements.
Video credit: Proto1Manufacturing
Flanging forms a lip or flange directly on the end of the pipe. Flanging can be performed on cold or heated pipes.
Chamfering is to cut away a right-angled edge or corner to make a symmetrical sloping edge. The small cuts are typically at 45 degrees
Roll beading is the process of crimping the end of a cylindrical metal tube to form a spout-like shape. This may be done to strengthen and protect the shape of the rolled metal form.
Flaring can be used in conjunction with tube reducing to manipulate tube endings to suit the specified application.
Flaring Tube Ending
Image Credit: Techniswage
Facing is the process of removing metal from the end of a workpiece to produce a flat surface.
Facing Tube Ending
Image Credit: Mini-lathe.com
Notching create a nick or indentation such as a small V-shaped cut in the edge or on the surface of a tube.
Methods and Tooling
- The ram forming process, also referred to as bulldozing, uses one or more form tools, or punches, that are rammed over the end of the tube which is held in place by clamp blocks. The process uniformly works the full circumference of the tube end. Hydraulic systems typically are most effective in delivering the power and speed required.
Ram forming provides a consistent finished part, but it cannot be adjusted to compensate for variation in the amount of spring back.
Tooling for ram-type end forming includes:
- A punch
- A shuttle block
- Segmented end forming is used to reduce or expand the end of a tube. Unlike ram forming, segmented tube forming does not require clamping of the tube. The most common application of segmented end forming is when one tube slips into the end of another tube. For reducing the tube, the process uses a set of segmented dies. This squeezes the dies together to reduce the tube's diameter. Expanding the tube uses segmented tools or fingers. They start out packed together so they fit inside a tube. The fingers are spread uniformly until the tube reaches the finished diameter.
A disadvantage to segmented tooling is it can change the workpiece's diameter. The standard reduction is about .250 in. in diameter with each tooling set.
Tooling for segmented end forming machines includes:
Closing dies for reducing the tube diameter
Internal dies (referred to as expanding fingers) for expanding the tube
The rotary forming process is typically produces flared ends on tubes and hose beads. The specific advantage of this process is that it can be used to work around the circumference of a tube, especially where sharp angles and radical diameter changes require more gradual work on the tube.
The internal roll forming process has slower cycle times than ram forming, but can produce tighter tolerances. Tooling for internal roll forming includes:
Serrated clamp jaws to hold the tubing in place while axial pressure is applied to the end of the tube.
Selecting a tube end forming method
Bend Tooling INC.