Picture this: you’re sitting on your couch, drinking coffee, browsing through the different tv networks when you come across an ad for a cutting torch. Curious about the device’s function, you watch the whole demonstration. By the time the person starts using the cutting torch, you’re so hooked by the ads’ persuasive words and demonstration that you quickly grab your keys and drive to the nearest hardware store. Picking up the same device, you pay for it and happily drive home.
You quickly read the manual instructions as soon as you’re home but couldn’t understand a thing. At this point you wonder, Is there a cutting torch setup for newbies like me? Good news for you, we have created a detailed guide on how to set up a cutting torch—specifically an oxy-acetylene cutting torch setup. So, if you want to efficiently and correctly use your new baby, keep on reading!
What Are Oxy-Fuel Cutting and Oxy-Fuel Welding?
Oxy-fuel cutting and oxy-fuel welding are two processes that utilize oxygen and fuel gas for metal fabrication. Oxygen-acetylene welding was developed in 1903 by French engineers Charles Picard and Edmond Fouché. Oxygen-acetylene welding is the process of using acetylene and oxygen to generate the highest flame temperature, which melts the workpiece material.
While people often interchange them, oxy-fuel welding and oxy-fuel cutting are two different things. In oxy-fuel welding, you use a welding torch to weld metals. The process involves heating two metal pieces to share a pool of molten metal. The molten metal pool is supplied with filler metals.
In oxy-fuel cutting, the torch heats the metal at a certain temperature, which is then reheated into a metal oxide by a stream of oxygen. This article will focus more on oxy-acetylene cutting, which is the combustion of pure oxygen and acetylene to melt steel.
The Oxy-Acetylene Torch
The most common cutting torch used by many professionals is the oxy-acetylene torch. It is the most affordable tool that allows you to merge metal pieces together using extreme heat. You need to bring the two metals to a molten state then include a high-pressure stream of oxygen for this to be achieved. In this way, it will burn the metal and carry away the oxidizing residue.
Since you will be handling equipment with high heat and flammable supplies, you’ll need to understand what is stated in the Occupational Safety and Health Administration:
Workmen in charge of the oxygen or fuel-gas supply equipment, including generators, and oxygen or fuel-gas distribution piping systems shall be instructed and judged competent by their employers for this important work before being left in charge. Rules and instructions covering the operation and maintenance of oxygen or fuel-gas supply equipment including generators, and oxygen or fuel-gas distribution piping systems shall be readily available.
Proper training must be completed before you can operate the device. You may ask for a mentor to guide you or attend special workshops and training opportunities in your area. You can also get supplemental help from guides and ebooks. Fast learners can simply follow this in-depth guide.
Safety Guidelines in Handling Cutting Torch
Before discussing the cutting torch setup, we need to know the safety guidelines first. These guidelines include proper storage, handling compressed gases, and leak detection. Take note of these before you start setting up and using the cutting torch.
Properly Store the Gases
Gases are typically stored under high-pressure steel cylinders and are color-coded to avoid interchanging with the other gases. For oxygen, the shoulder of the cylinder is white and is maroon for acetylene. The oxygen cylinders have a right-hand thread, while acetylene cylinders have a left.
You turn the knob counterclockwise to open the cylinder and clockwise to close it. It’s of utmost importance that you separate the fuel gas cylinders from the oxygen cylinders because a mixture of the two can cause an explosion. Store these powerful gases in an area that is free of combustible materials.
Proper Handling of Compressed Gases
The cylinders must always be securely fastened, and the valve guard should never be loosened. Each cylinder is fitted with a regulator to reduce the gas pressure inside. A regular one has two gauges: one for the gas inside the cylinder and the other for the gas fed to the torch.
Before you attach the regulator, make sure that the pressure adjustment screw is detached to prevent the unregulated flow of gas into the system. Check the cylinder joints, too, if it's clean. Valve threads should also be cleaned before you screw them in the regulator.
When mixing gases in the hand-held torch, make sure it is in the right proportions. The hoses should also be color-coded as with the cylinders. Keep the hoses as short as possible and periodically check if they are near any hot or sharp object.
When connecting the system, the torch and hoses must be purged to remove any combustible gas mixtures. Purging the hoses and torch must be done in a wide-open space rather than a confined one. Use protective equipment on your face and eyes, and wear non-combustible clothing.
It is imperative to detect leaks before you start welding. You can easily detect acetylene due to its smell. Another way is to apply a weak detergent solution in water or use a leak detecting solution. Apply this liquid to the joints, and when bubbles form, then gas must have leaked.
Best Cutting Torch and Regulator Setup
Once you are able to take note of the safety procedures, it’s time to set up your new device. Do note that oxy-fuel cutting can be used for plain carbon steels, low-alloy, and other ferrous metals. Don’t use it on cast iron or stainless steel. This guide highlights the three crucial parts of a cutting torch setup. If you're looking for a propane cutting torch setup, you can also apply the guide below. Here’s a 4-part manual on how to set up a cutting torch.
Part 1: Attaching pressure-reducing Regulators
- Prepare the oxygen and acetylene cylinders.
Put the cylinders in an upright position. Secure it with a chain on a wall, workbench, or post. Then, clean the valve outlet from dust and dirt. You need to clean it to avoid debris from entering the other parts of the torch.
- Connect the regulators to the cylinders.
Once you are able to prepare the cylinders, you can then connect them with the regulators. If the regulator and cylinder don’t fit with each other, use an adaptor. Tighten the regulator with a wrench. Do note that the valve in the regulator must be closed before allowing cylinder pressure in the machine. Hence, you need to turn the pressure-adjusting screw counterclockwise.
- Open the oxygen and the acetylene valves.
Open the valve gradually and very slowly, pause until the pressure hand stops moving, then continue to fully open the valve. Be careful not to open the valve more than one and a half turns—this should never be the case. Then leave the wrench on the acetylene valve, so in the case of an emergency, you don’t have to look for it elsewhere.
Part 2: Connecting Gas Supplies to the Torch
Use the correct hose for the cutting torch.
The oxygen hose has a green cover, while the acetylene hose has a red cover. Do not interchange the two. Replace it if it is broken and don’t use a lubricant. Then, attach the hose to the regulator and the torch. Do the same for the acetylene hose with the acetylene regulator. Don’t forget to tighten the hose connections using a wrench.
Part 3: Adjusting the Cutting Torch to Get the Correct Operating Pressure
- Adjust the pressure of the cutting torch.
Turn the oxygen regulator-pressure adjusting crew to get the pressure you want. Then close the torch oxygen valve. Remember that you must not put the pressure higher than recommended.
- Adjust the acetylene adjuster screw.
The next step is for you to adjust the acetylene adjuster screw. The working pressure must not be more than 15 psi. Once you are able to obtain the desired pressure, close the valve. Remember that you must not release acetylene near a source of ignition.
Part 4: Start Using the Cutting Torch
- Read the manufacturer’s instructions.
Once the cutting torch is properly set up, the instruction manual read, and you have all safety measures in place, you can finally start to use it. Specifically, check the warnings and helpful tips, so you are informed of actions you can take in the face of an emergency.
- Open the valve and light the flame.
To start using the torch, open the acetylene valve ½ turn and light it using a friction lighter. If you don’t see a flame, you should check your connections. Afterward, adjust the acetylene flow by turning the torch acetylene valve.
- Stop using if a backfire or flashback occurs.
Backfire happens when the cutting torch comes into contact with metal. When this happens, simply light it up again. However, if it keeps on occurring even without any contact with metal, check the operating pressures. As for a flashback, turn off the torch and check the setup. Use it again once it’s cooled down.
Setting up a cutting torch is not easy. It can be confusing for a beginner like you, but you can quickly learn the process with the right training and reading materials. We hope you were able to pick a few tips from our handy guide, and don’t forget to exercise caution when using this powerful piece of equipment.