What is a cutting torch and what exactly is oxy acytelene welding?
Cutting and welding has revolutionized manufacturing and construction companies.
They are both very important processes in a multitude of industries.
Dating to 1903, torch cutting is used to cut metals by fueling gases and oxygen.
Below we will discuss what it is, why you need it, how to use it, the features they provide, and the equipment needed to cut properly and safely.
What is torch cutting and why do you need it?
According to the Merriam Webster Dictionary, torch cutting is “a blowpipe by which metal is preheated with a flame and then oxidized rapidly and removed by a jet of oxygen issuing centrally through the preheating flame.”
The base of torch cutting is the torch outfit, which produces heat by burning acetylene gas. The torch outfit can cut, weld, braze, and heat various metals.
A torch outfit is extremely versatile and has dualine hose transfers for acetylene and oxygen.
They consist of high pressure cylinders and pressure regulators. The torch handle holds a cutting attachment for the cutting.
For this to be done properly, a tip needs to be attached to the end of the torch.back to menu ↑
How to use a cutting torch
Preparation works before lighting
First of all, mark and measure your cutting path.
Now, the first thing you do when torch cutting is make sure you have the correct equipment and supplies. Especially you need protective clothing and safety goggles. Take a look at the cutting tip and clean the hole if not done already.
Attach your hoses to the gas bottles. Oxygen hose usually is blue (black on old equipment). Acetylene hose is red. Carefully read your manual, make sure everything is installed correctly.
Make sure the valves of your torch, the gas cylinders are still closed. Make sure regulator pressure adjustment screws are backed out.
How to light a cutting torch?
Open the oxygen bottle and the acetylene bottle very slowly. Adjust regulator pressure according to your cutting tip pressure ratings.
This means, most of the times the acetylene regulator pressure should be set somewhere between 5-7 psi and the oxygen bottle should be set to around 40 psi.Never use fuel pressure above 12-15 psi because it gets instable and can blow up.
Open your torch valves seperately and fine adjust regulator pressure.
Flush seperately the oxygen and fuel gas hoses.
Then open the acetylene gas valve approximately one half of a turn. Light the torch turning away from you by using your striker.
Turn it up until the flame is away from the torch and back off until it comes to the tip.
Now it’s time to adjust it for cutting.
How to adjust the right settings – what is the right flame color?
After you did the steps above you can additionally open the oxygen valve and adjust it to neutral flame.
The correct flame color should always be cherry red and the temperatures should reach 3,480 degrees Celsius. Now is the time to see that the preheat flames are sharp.
You will start to see small white cones when the oxygen valve is turned. Before you start cutting the metal, pre-heat it and start at the edge until it starts to glow. Press down on the lever and drag the torch along the path you marked.
When cutting, keep the flames to the point where it touches the metal. Torch cutting can cut up to 12 inches thick.
How to shut-down the oxy-acetylene cutting torch
Once you are down cutting, close the oxygen first and after that acetylene valve completely.
Oxygen-acetylene torch cutting can be dangerous due to the instability of the fuel and the high temperatures it can reach.
Plus, purchasing acetylene can be expensive when compared to other gases.back to menu ↑
What are the different types of torch cutting?
There are 3 different types of torch cutting:
- Plasma cutting,
- Laser cutting
- Oxy-acetylene torch cutting
Plasma cutting is a process where inert gas is blown through a nozzle at a high speed which forms an electrical arc.
The arc is applied to the metal being cut and provides a quicker cut and is an operational friendly process to cut metal.
Laser cutting is a process where metal is melted by a thin and focused beam of intense energy which vaporizes and melts the metal.
The material is melted or burnt away with high pressure and results in separating the metal. Laser cutting is computer-controlled to create a clean and accurate cut. They are mainly used where an intricate and precise cut is needed.
Oxy-acetylene torch cutting
Oxy-acetylene cuts metal by utilizing oxygen to burn metal.
Heating the metal is caused by an acetylene flame that adds oxygen to burn the metal and increase the temperature. Elements in the metal begin to oxidize due to the heat of the oxygen. The pressure of the oxygen and the torch forces separates the metal.
These torches only work on oxidized metals, which excludes aluminum and copper.
Read also: MIG welding – how to
There are 2 different types of torch cutting tips:
one-piece and two-piece.
They both can handle light and heavy preheats and have preheated holes.
Torch cutting provides many benefits such as versatility and power, portability, and the ability to cut thick material with a range of tips.
You don’t need a high skill level and torch cutting is easily mastered with practice.
Depending on the manufacturer, the handle may make it easier to hold and takes away operator strain and pressure throughout the cutting process.back to menu ↑
Top cutting torches
- Perfect for a multitude of applications
- This outfit is designed for use with acetylene fuel gas but can operate on propane by simply changing to propane tips.
- Medium duty outfit versatile yet economical
- NOTE: User manual is attached - kindly refer it
- High quality heavy duty three piece torch kit, CA2460 cutting attachment, 315FC torch handle
- Constructed with high strength alloy, heavy duty stainless steel and durable brass
- Cutting torch and handle are ready for multiple gas options; Oxy-Acetylene, Propane, Butane, Natural and LP Gases, and Propane
- Perfect for welding, soldering, cutting, gauging and other applications
- Nozzle #1 and No. 0, 2, 4 Welding Nozzles
- 15' x 1/4" Welding hose
- A complete set includes a torch handle, oxygen regulator and acetylene regulator
- Precision Welding, Cutting, Brazing, Soldering
- Made Of High Quality Materials, Sturdy And Durable
- Includes The Necessary Accessories Of Welding And Cutting, Storage Case Included
- Perfect For An Amateur Metalworker Or A Seasoned Professional
Equipment for torch cutting
Safe equipment is always the best route to go when using any cutting assembly. To use the equipment effectively, you will need:
- Safety glasses
- Welding gloves
- Welding helmet (also read: best auto darkening welding helmets)
- Hand-held striker to create the spark to light the acetylene
- Cylinder cart to hold the cylinders and accessories securely
- Tape measure
- Speed square
- Flame resistant long sleeve shirt
- Leather boots
- Oxygen acetylene cutting torch
- Starched blue jeans
Summary of torch cutting
Cutting metals has been easier and more efficient due to torch cutting and the handy resources it provides.
It is a staple in the construction and manufacturing industries and should be a staple for your house as well.
Popular brands include Victor Cutting, ESAB, and Smith Equipment.
Each manufacturer has tips and tricks to help you along your cutting journey.