What Is a Flame Cutting Service?
A flame cutting service is a process that uses gas and oxygen to cut metals.
A flame cutting service heats the base material to a high temperature using combustion gas and then blasts it with high-purity oxygen to oxidize and dissolve it, thereby cutting the metal. A flame cutting service is also called oxygen cutting because it uses a chemical reaction between iron and oxygen. The gases used in flame cutting services are mainly acetylene, natural gas, and propane gas.
The advantage of a flame cutting service is that even thicker metals can be cut quickly. It requires relatively little equipment and is superior to other cutting methods in that it does not require electricity. The disadvantage is that the cut surface is rough due to manual labor. It is also important to note that because flammable gas is used, there is a risk of accidents. Flame cutting services operators are required to take a “gas welding skills training course.”
Uses of Flame Cutting Services
1. Steel Cutting
Flame cutting services are highly efficient in cutting steel, and can cut steel plates as thick as several hundred millimeters. On the other hand, it is not suitable for cutting materials such as aluminum and stainless steel, which do not oxidize easily. Flame cutting services are not suitable for aluminum and stainless steel because they produce oxides with high melting points. In such cases, plasma or laser cutting is used.
2. Underwater Cutting
Equipment called an “underwater cutter” is used for underwater metal cutting. Currently, it is possible to work in water depths of up to approximately 70 meters.
Principle of Flame Cutting Services
Flame cutting services are a method that uses chemical reactions of oxidation and combustion. Simply heating a metal to a high temperature is not enough to cut it. Oxidation is the compounding of metal and oxygen, which produces heat as it oxidizes.
Combustion is a redox reaction that violently oxidizes and produces light and heat. Flame cutting services cut steel materials by artificially creating the principles of oxidation and combustion.
Specifically, flame cutting services first heats the cutting area to 800-900°C with combustion gas to oxidize it. Next, a fire is set and high-purity oxygen is sprayed to cause combustion, melting only this portion of the material. Flame cutting services are possible because the oxygen gas blows off the melted portion, and combustion and melting continue one after another.
Features of Flame Cutting Services
1. Thick Materials Can Be Cut
Flame cutting services are more suitable for cutting thicker materials than plasma cutting services or laser cutting services. Flame cutting services can cut materials as thin as a few millimeters to as thick as several hundred millimeters, and are mostly used for cutting thick steel plates of 50 mm or more.
2. No Electricity Required, Small Equipment
Flame cutting services do not require electricity compared to plasma, laser, and arc cutting methods. Flame cutting services require only a torch, gas cylinder, pressure regulator, and hose. It is an inexpensive method to introduce.
3. Operator Skill Is Required
Flame cutting services have a rough cross-section and rely heavily on the skill of the operator. Manual adjustment of fire intensity, oxygen level, cutting speed, and arm movements require skill. In particular, cutting is not only straight lines but also curves, arcs, and other various shapes, requiring the ability to improve accuracy.
4. Slow Cutting Speed and Susceptible to Thermal Deformation
Flame cutting services have the disadvantage of slow cutting speed compared to plasma cutting, laser cutting, and arc cutting. Another disadvantage is that the material is easily deformed due to local heating. Preheating of the entire part is used.
Types of Flame Cutting Services
Flame cutting services can be broadly classified into the following three types according to the gas used.
1. Acetylene Gas Flame Cutting Services
Acetylene gas is the oldest gas in use, dating back more than 100 years, and is still widely used today. Its specific gravity is lighter than that of air, making it suitable for outside work, and its high combustion temperature makes it easy to work with.
2. Propane Gas Cutting
Propane, also called LP gas, is the second most widely used gas after acetylene. It is heavier than air in specific gravity, so it is not suitable for work in a small room. It takes longer to work with propane because of its relatively low combustion temperature, but there is less risk of ignition and it is safer.
3. Methane Gas Cutting
Methane is also known as LNG or city gas. It is lighter than air in specific gravity and less flammable, making it relatively easy to handle. It has a lower combustion temperature and is less efficient than propane.
Other Information on Flame Cutting Services
Qualifications for Flame Cutting Services
Flame cutting service operators are required to take a “gas welding” skills training course. This course is open to those 18 years of age or older and includes both classroom and practical training. The course covers three subjects: laws and regulations, knowledge of oxygen and gases, and the structure and handling of facilities and equipment.
After obtaining the gas welding skills training qualification and at least three years of work experience, the trainee will be qualified to take the gas welding operator’s license examination. This qualification is necessary to direct and manage gas welding operators.