Metal fabrication is a term that encompasses a large number of processes in manufacturing. Tubular steel fabrication refers specifically to those process that prepare and assemble the metal tubing to create a finished product. Tubular steel is only one of many metal products that can be fabricated.
Cutting in metal tube fabrication is specifically when the manufacturer cuts the tube to size. This can be done in multiple ways:
1. Sawing - Sawing is the least effective cutting method for metal tubing, but it can be done.
2. Laser - Laser cutting uses a highly focused laser beam to cut straight through the metal. Laser cutting is an economical cutting method as the laser doesn't dull and there is little waste produced.
3. Plasma - Plasma cutting uses pressurized gases and electricity to make clean cuts. The extreme heat of the plasma jet melts the metal it touches rather than physically cutting with a tool.
4. Flame - Flame cutting is actually performed by a jet of oxygen rather than fire, as the name implies. The item is heated, and then the oxygen burns the metal during heat formation.
5. Waterjet - Technically known as abrasivejet cutting due to a mixture of abrasives in the water, waterjet cutting is used on metals that are sensitive to high temperatures.
Piercing involves placing holes in tubing in some way - most commonly punching, though drilling is also an option.
6. Punching - Punching uses a punch press to pierce tubular steel. The process is very similar to a paper hole punch. Punching is a cheap, quick way to make a lot of holes very quickly.
7. Drilling - Drilling is generally only used on very thin-walled tubing, as the debris from drilling thick metal can clog the tooling. There are special drill techniques that make it easier (such as peck drilling), but punching is overall a better method.
8. Rotary Draw Bending - Rotary draw is the only type of bending that uses mandrels to maintain the structural integrity of the tube. Rotary draw is used for tight bends and especially thin-walled tubes.
9. Roll Bending - A gentle type of bending that is great for continuous bends like coils.
10. Compression Bending - Uses pressure to form the tube around the shape of a die.
11. Freeform Bending - Relies on push bending to form non-standard bends.
12. Heat Induction - The tube is heated to soften the metal, then bent with pressure.
13. Sand Packing - The tube is filled with sand, heated, then bent around pins with a mechanical force. The sand helps the tube retain its shape, and reduces the chance of wrinkles in the metal.
14. Press Braking - A tube can be pressed if it is notched to allow the die to bend the bottom wall. Here's a video that shows how it's done:
15. Profiling - Removing sections of the tube to allow for assembly with other pieces. Profiling is important when two parts need to be tightly joined.
16. Welding - There are a few different types of welding: manual metal arc welding (MMA), metal active gas welding (MAG), and submerged arc welding (SAW). All three can be used for different purposes in one factory. Welding is a permanent attachment technique that melts metals at their connection point.
17. Binding - Attaching components with adhesives such as glue, cement, and paste.
18. Riveting - Attaching two parts with rivets. Rivets are permanently fastened by bucking or upsetting the tail, causing it to expand and hold in place.
19. Fastening - Screws and bolts are the most common metal fasteners available.
These are the most common processes that fall under fabrication. Some consider coating and finishing to be part of the fabrication process as well, while others keep fabrication and finishing strictly separate.
If you're interested in tubular steel fabrication services, you might also be interested in the most common uses for steel tubes.