A rough idea from the name is that orbital welding involves circular motions. Well, you are right. Orbital welding is a type of welding where the arc rotates 360 degrees continuously through a static object. Welders generally use this method for tubes because it more easily provides a uniform weld which can be difficult to achieve with manual welding.
Table of Contents
History Of Orbital Welding
In the 1960s, it was challenging to weld pipes together using the MIG welding process that requires a gun. Also, only welders with exceptional skills could use the TIG welding process to join pipes and tubes. That was when Roderick Rohrberg of North American Aviation created the process to correct fluid leakage from pipes on research planes.
Orbital Welding provides a simpler alternative to the TIG welding process. It automates TIG welding for pipe and tubing uniform welding around a tube that would otherwise be much more difficult with a manual welding process. Although designed primarily for pipes and tubes, orbital welding also works on many metals and alloys.
Equipment Used In Orbital Welding
The equipment used for orbital welding comprises three parts; the power supply, a cooling system (either water or air), and the weld heads.
1. Power Source
The power supply or power source is the controller of the orbital weld equipment and where the weld programming is performed. It is based on a microprocessor and controls all the weld parameters. It dictates the amperage, weld speed, pulse, and purge time and communicates to the weld head.
The power source of a welding machine may also have wire feed abilities, giving it additional controls. The power supply can include provisions to retract and advance the wire, control the wire feed speed, etc. An advanced orbital welding machine may have a power source that stores weld programs and documents welds.
2. Water Cooling System
A cooling system is an important feature of the orbital welding system. A water-cooling system is common, but some welding systems use an air cooling system.
The water-cooling system connects the weld head and holds the cooling fluids. A low conductivity coolant or a jug of antifreeze glycol is recommended for coolant fluid.
When using a pump, the water-cooling system flows the coolant fluids into the weld heads. The cooling system allows the weld heads to run at full capacity and prevents overheating during a weld.
3. Enclosed Weld Heads
As the name suggests, enclosed weld heads are closed and designed to create an inert atmosphere chamber to surround the weld joint. They are also called closed, or fusion weld heads.
Enclosed weld heads are effective because they provide a continuous shield flowing with inert gas during the pre-purge, the weld sequence, and the post-purge. They allow the cooling of the weld before exposing it to external air.
The design of an enclosed weld head reduces the risks of blemishes or imperfections and supports sanitary welding. It is important when welding materials for the food, beverage, and pharmaceutical industries.
4. Open Weld Heads
Generally, the open head weld is used for pipe welding applications. However, open frame weld heads offer two distinct styles; the clamping head style and the open frame head.
As the name suggests, the clamping head style uses a vise clamping system to launch the workpiece and attach it to the track.
With the open frame head, the joint component has to be tack welded into place or held with a bridge clamp. Because the shield gas is limited, the electrode and weld mix together beneath the electrode, this causes a heat-tint discoloration on the outside diameter of the weld.
Regardless of the style of open weld head, you are using, you will require a wire filler, and using wire filler for orbital welding is not fully automatic. Some adjustments such as torch steering or arc gap adjustment will be needed, which takes more skill.
Types of Orbital Welding
There are three main types of orbital welding.
- Gas tungsten arc orbital welding
- Metal inert gas orbital welding
- Fusion orbital welding
Gas Tungsten Arc Orbital Welding (GTAW) Orbital Welding
It is the same as Tungsten Inert Gas (TIG) welding, but it is done with filler metals. It requires welding guns and is similar to the traditional welding style.
Metal Inert Gas (MIG) Orbital Welding
This orbital welding involves thicker materials, so the welding process is ideal for heavy-duty materials. It produces stronger welds than TIG when a flux-core wire is used in the welding process. Rather than the welding gun used in TIG orbital welding, a welding head is used.
Fusion Orbital Welding
Another similar process to TIG orbital welding is fusion orbital welding. This welding process requires no filler metal; hence the weld is weaker. Rather than adding a filler metal, two joints are fused. Though it produces weaker welds, it is quite useful for some applications.
Uses Of Orbital Welding
- We stated earlier that orbital welding produces high-purity welds and is often used for producing clean-room parts in the semiconductor industry.
- It is also used for pipework in several industries.
- It is used in food processing, automotive, aerospace, chemical engineering, pharmaceutical, shipbuilding, and biotechnology industries.
Advantages of Orbital Welding
Some perks of orbital welding are that it produces clean and consistent welds of high quality. Other advantages/benefits are:
Increased Productivity
Wels sequences are easily held together with orbital welding, increasing productivity and output.
Consistent Weld Quality
With the orbital welding machine, you can easily set the parameters for a weld cycle. This weld cycle can be saved and repeated to achieve extraordinary precision and consistency.
Operator Skill Levels
Since orbital welding is automated, trained, skilled mechanics can perform orbital welds. Also, the skill level required is lower than that of manual welders. With some training, any welder can perform an orbital weld.
Environmental Conditions
Once the weld head is in position, the weld can be completed from a distance and monitored over video transmission. Hence, it can be performed in poor environmental conditions with restricted visibility.
Improved Safety
Since orbital welding can be done from a safe distance, it offers increased safety.
Final Thought
You can see that above all things, orbital welding offers a high level of safety, increased productivity, and professional work. Welding accessories are always nice to have as well no matter the type of welding. If you want to venture into orbital welding, simple training that teaches you the steps is all you need.
