Ultimate Guide to Orbital Welding
In this guide, we will cover everything you need to know about orbital welding.
- What is Welding?
- What is Orbital Welding?
- When to Use Orbital Welding?
- Advantages of Orbital Welding
- Equipment Required for Orbital Welding
- Achieving the Best Quality Weld: Preparation Process
- Orbital Welding Machine Brands
What is Welding?
Simply put, welding is a process where two separate pieces of metals (known as electrodes) are fused together using high heat.
Watch a basic welding demonstration here:
Welding Electrodes: Consumable VS Non-Consumable
There are 2 categories of welding electrodes.
What is Orbital Welding?
By definition, orbital welding refers to automated welding of secured tubes or pipes with the electrode rotating (or orbiting) around the tube.
It’s a specialised type of welding where the arc rotates 360° around the in-place object (pipe/tube) continuously.
How an automatic welding machine works:
History of Orbital Welding
Orbital welding was developed in the 1960s when there was a need for a more precise welding method in the aerospace industry.
This particular process then started to find its place in varying fields from automotive engineering to food processing.
When to Use Orbital Welding?
So, how do you choose between using welding and orbital welding?
Orbital welding should be used if
✓ The production involves difficult positions to handle manually
The location where the welding is taking place and where the machine itself is placed will affect the safety of the welder. Also, it plays a part in determining the difficulty of completing a task.
Hence, if the welder’s safety will be compromised, an automated procedure is advised.
✓ Large quantities of welds are required to be produced
Since the process is fully automated, orbital welding is perfect to produce large quantities of welds because of its repeatability.
On the other hand, if the production requires
- Small quantities or
- Customised parts
A combination of semi-automatic and mechanised machines may be used.
Advantages of Orbital Welding
Equipment Required for Orbital Welding
AXXAIR SASL 200/300
1. Programmable Power Supply
Portable Power Sources
Weight: <30kg Current: up to 160 ampere Voltage: 1-phase 230 V
- Portable: lightweight enough for the operator to carry it to the site
- Compact: small enough to pass through manhole if required
- Controls up to 4 axes of settings
Shielding gas flow, weld current intensities and pulse rates, travel speed of the welding head and wire feeding operations
Medium-sized Mobile Power Sources
Current: up to 400 ampere
Voltage: 3-phase 415 V
- Heavyweight: fixes on wheels for mobility
- Controls up to 6 axes of settings
Shielding gas flow, weld current intensities and pulse rates, travel speed of the welding head, wire feeding operations and arc voltage control and oscillation.
Full-size Power Sources
Current: 300 – 600 ampere
Voltage: 3-phase 415 V or multi-voltage input
- Controls 6 axes or more
2. Weld Head
- Holds electrode in place
- Applies pressure on workpieces to be welded
- Flows welding current
- Maintain heat temperature
Tube-to-tube Welding Heads
AAXAIR SATF 40nd
- Closed Chamber Welding Head
Diameters: 1.6mm – 168mm
Autogenous welding of tubes without filler wire
AXXAIR SATO 40E0x
- U-type Open Welding Head
Diameters: 8mm – 275mm
Typically used for orbital TIG welding with or without filler wire
- Carriage-type Open Welding Head
Diameters: from 114 mm (outer) onwards
Orbits around tubes/pipes on designated rails with or without filler wire
Tube-to-tube sheet Welding Heads
- Enclosed Orbital Tube-to-tubesheet Welding Heads (without filler wire)
Diameters: 9.5mm – 33.7mm (internal)
TIG welding (GTAW) applications without filler wire
- Open Tube-to-tubesheet Welding Heads (with or without filler wire)
Diameters: 10mm (internal) – 60mm (outer)
3. Wire Feeder
Depending on the mobility of the welding equipment, a wire feeding mechanism may be required. It can be built into the welding head or come as a separate device.
4. Coolant system (Water/air)
Function: to prevent welding equipment from overheating
This is imperative in order to protect the equipment from heat damage and the operator from heat injuries.
There are 2 main types of coolant systems: water or air.
Air VS Water Coolant System
Conclusively, achieving a quality weld is dependent on the knowledge and experience of the operator to set the precise parameters.
Achieving the Best Quality Weld: Preparation Process
Planning is key when trying to achieve the perfect weld.
Other than preparing the materials and ensuring a safe environment, you should also accustom to the equipment.
1. Tube/Pipe End Preparation
Ensure that your cutting blades have been sharpened to obtain a clean cut without deforming the pipes.
2. Material Selection
With the same parameters, make test welds using different batches of metals to confirm that the end products are consistent.
3. Weld Joint Alignment
- Alignment: Make use of engineering clamps to align and hold the welding pipes into place. This speeds up the preparation process.
- Gaps: No more than 5% of pipe/tube wall thickness
- Tube wall thickness: ±5% to ensure weld quality
4. Welding Gases
The suitable gas mixture depends on the fusing materials. Some common mixtures are:
- Argon and Hydrogen
- Helium and Argon
5. Tungsten Electrode Geometry
Source: Winning Preparation
- Taper (Included Angle)
Source: 8 Practical Orbital Welding Tips
- Tip Diameter
Source: 8 Practical Orbital Welding Tips
Your choice of tungsten electrodes should be an optimal balance of electrode life and welding performance.
6. Welding Parameters
Each welding machine comes with adjustable parameter settings. Prior to setting, you should research on the welding machine and equipment so as to be able to tune to precise, accurate parameters.
Orbital Welding Machine Brands
Price range: $$, 20k+
As a firm believer of constant improvement, Swagelok aims to be the go-to advisor for all things related to science, logistics and engineering.
Price range: $$$, 25k+
Another outstanding brand that is well-known for its quality, durability and functionality is Arc Machines Inc. (AMI). Established in 1976, they have since clinched over 3,000 partnerships all over the world.
Price range: Available upon request
POLYSOUDE boasts a “zero risk and zero defect” approach when working with clients. Their products provide innovative solutions for your operational needs, regardless of the industry your business is in.