what type of flame is required for oxy fuel cutting

Can oxy fuel cutting be used with other materials?

Feb 13, 2020 · What type of flame is required for oxy fuel cutting? Acetylene produces the highest flame temperature of all the fuel gases. The maximum flame temperature for acetylene (in oxygen ) is approximately 3,160°C compared with a maximum temperature of …

What is the best gas for flame cutting?

Flame torch also called fire gun. With different gas, the torch has different structural. Most used is Oxygen-Acetylene gas torch, acetylene pressure at 0.01 to 0.12 Mpa, Oxygen pressure 0.50 to 1.0 Mpa. Two different gas burned in it’s own channel and mixed together in oxy fuel cutting torch, the flame could be adjusted manually.

What kind of gas is used in a cutting torch?

Dec 15, 2021 · A carburizing flame looks much the same with MAPP gas or acetylene. It has a yellow feather on the end of the primary cone. Carburizing flames are obtained with MAPP gas when oxy fuel ratios are around 2.2:1 or lower. Slightly carburizing or “reducing” flames are used to weld or braze easily oxidized alloys such as aluminum.

What is oxy acetylene cutting?

8 rows · There are four basic requirements for oxy-fuel cutting: ... Acetylene produces the highest ...

What type of flame is required when carrying out oxy fuel cutting?

Neutral flame is used for joining and cutting of all ferrous and non-ferrous metals except brass.

What flame should you have for general use on an oxy fuel torch?

1:235:36How To Light, Set and Extinguish an Oxy-Fuel Torch Flame - YouTubeYouTubeStart of suggested clipEnd of suggested clipRemember we want a neutral flame and when using acetylene fuel gas that can be achieved.MoreRemember we want a neutral flame and when using acetylene fuel gas that can be achieved.

What type of flame is oxy acetylene?

There are three basic types of oxy-acetylene flames viz., carburising or reducing flame, neutral or balanced flame and an oxidising flame. Apart from the chemical nature, these flames also differ in structure and shape.

What flame do we need for cutting?

Flame cutting uses a neutral flame to heat the material up to its kindling temperature. When this is reached, the operator presses a lever that releases an additional high-flowing stream of oxygen to the flame.Feb 13, 2019

For what purpose oxy-acetylene flame is used?

Acetylene produces a flame temperature of ~3100 degree Celsius along with oxygen. This high flame temperature makes acetylene a suitable choice for gas welding steel. 2. Welding: When burned in oxygen, acetylene produces a reducing zone, which easily cleans the metal surface.

What do the preheat flames do while oxygen fuel cutting?

After the plate is preheated and the burning starts, the preheat flame is turned down to a lower setting. But the preheat flame continues to provide the heat & ignition source, while the cutting oxygen stream provides the oxidizer, and the steel itself is the fuel.

What are the three types of oxy-acetylene flame?

There are three different types of flames in gas welding, neutral, carburizing, and oxidizing. The welder can adjust the oxyacetylene flame by adding more or less oxygen to the acetylene flame based on the job requirement.

How do you set a neutral flame with oxy-acetylene?

0:181:55Firepower How-to: Setting a Neutral Flame - Cutting Attachment - YouTubeYouTubeStart of suggested clipEnd of suggested clipYou will hear a slight hissing sound at this point depress. And release the cutting oxygen lever.MoreYou will hear a slight hissing sound at this point depress. And release the cutting oxygen lever. You may need to readjust the flame at this point typically the flame becomes slightly carburizing.

How do you adjust an oxy-acetylene flame?

0:443:36Oxy Acetylene Welding | Gas Welding | Adjusting The Flame - YouTubeYouTubeStart of suggested clipEnd of suggested clipThis amount of gas should come close to producing the right sized flame once the acetylene isMoreThis amount of gas should come close to producing the right sized flame once the acetylene is adjusted slowly open the oxygen valve you'll start with a long flame.

How thick of steel can you cut with oxy-acetylene?

Oxy-fuel torches also offer versatility, as they are capable of cutting, welding, brazing, soldering, heating and gouging. The average hand-held system can cut steel 6 to 12 inches thick. However, some oxyfuel hand torches are able to cut steel more than 20 inches thick.Oct 31, 2019

How thick can an oxy-acetylene torch cut?

While the cuts may not be as clean, oxy-acetylene will carve through material up to 24 inches thick. That's 1,200% thicker material than plasma cutters can handle. Oxy-fuel is also one of the most portable methods of cutting. With just two gas tanks and a torch, you can cut anywhere.

What is the correct flame for preheating before cutting?

Neutral flamec) Neutral flame is used for most welding operations and for preheating during cutting operations. When welding steel with neutral flame, the molten metal puddle is quiet and clear; the metal flows easily without boiling, foaming, or sparking.

What is the oxidizing flame?

The oxidizing flame, which has an excess of oxygen, has a shorter envelope and a small pointed white cone. The reduction in length of the inner core is a measure of excess oxygen. This flame tends to oxidize the weld metal and is used only for welding specific metals. **Neutral flame.

What is the color of the oxyacetylene flame?

The flame changes to a bluish-white and forms a bright inner cone surrounded by an outer flame. The inner cone develops the high temperature required for welding. The temperature of the oxyacetylene flame is not uniform throughout its length and the combustion is also different in different parts of the flame.

What are the three basic MAPP gas flames?

As with any other fuel gas, there are three basic MAPP gas flames: carburizing, neutral, and oxidizing ( fig. 11-3 ). A carburizing flame looks much the same with MAPP gas or acetylene.

What is the color of the reducing or carburizing flame?

The reducing or carburizing flame can always be recognized by the presence of three distinct flame zones. There is a clearly defined bluish-white inner cone, white intermediate cone indicating the amount of excess acetylene, and a light blue outer flare envelope. This type of flare burns with a coarse rushing sound.

What is the white feather on a carburizing flame?

The** carburizing flame** has excess acetylene, the inner cone has a feathery edge extending beyond it. This white feather is called the acetylene feather. If the acetylene feather is twice as long as the inner cone it is known as a 2X flame, which is a way of expressing the amount of excess acetylene.

What is the ratio of acetylene and oxygen in a neutral flame?

They are shown in figure 11-2. The neutral flame has a one-to-one ratio of acetylene and oxygen. It obtains additional oxygen from the air and provides complete combustion. It is generally preferred for welding. The neutral flame has a clear, well-defined, or luminous cone indicating that combustion is complete.

What is oxidizing flame adjustment?

The oxidizing flame adjustment is sometimes given as the amount by which the length of a neutral inner cone should be reduced, for example, one tenth. Starting with the neutral flare, the welder can increase the oxygen or decrease the acetylene until the length of the inner cone is decreased the desired amount.

Which has a lower flame temperature, acetylene or propane?

Propane. Propane produces a lower flame temperature than acetylene (the maximum flame temperature in oxygen is 2,828°C compared with 3,160°C for acetylene). It has a greater total heat of combustion than acetylene but the heat is generated mostly in the outer cone ( see Table ).

Which gas has the lowest flame temperature?

Natural gas has the lowest flame temperature similar to propane and the lowest total heat value of the commonly used fuel gases, eg for the inner flame 1,490kJ/m 3 compared with 18,890kJ/m 3 for acetylene. Consequently, natural gas is the slowest for piercing.

What are the gases used in combustion?

The five most commonly used fuel gases are acetylene, propane, MAPP (methylacetylene-propadiene), propylene and natural gas. The properties of the gases are given in the Table. The relative performance of the fuel gases in terms of pierce time, ...

What is the highest temperature of acetylene?

Acetylene produces the highest flame temperature of all the fuel gases. The maximum flame temperature for acetylene (in oxygen) is approximately 3,160°C compared with a maximum temperature of 2,828°C with propane. The hotter flame produces more rapid piercing of the materials with the pierce time being typically one third that produced with propane.

What is the hottest part of a flame?

flame temperature - the hottest part of the flame is at the tip of the primary flame (inner cone) fuel gas to oxygen ratio - the amount of fuel gas required for combustion but this will vary according to whether the flame is neutral, oxidising or reducing.

How does oxygen jet work?

A jet of pure oxygen is then directed into the preheated area instigating a vigorous exothermic chemical reaction between the oxygen and the metal to form iron oxide or slag. The oxygen jet blows away the slag enabling the jet to pierce through the material and continue to cut through the material. Fig.1.

What is the reaction of fuel gas?

In the inner cone or primary flame, the fuel gas combines with oxygen to form carbon monoxide and hydrogen which for acetylene, the reaction is given by. Combustion also continues in the secondary or outer zone of the flame with oxygen being supplied from the air.

What is oxy fuel cutting?

In addition, oxy-fuel cutting is still widely used, both in heavy industry and light industrial and repair operations. In oxy-fuel welding, a welding torch is used to weld metals. Welding metal results when two pieces are heated to a temperature that produces a shared pool of molten metal.

What are the gases used in oxyfuel?

Other gases that may be used are propylene, liquified petroleum gas (LPG), propane, natural gas, hydrogen, and MAPP gas. Liquid fuel cutting systems use such fuels as Gasoline (Petrol) Diesel, Kerosene and possibly some aviation fuels.

What is an OAW torch?

A cutting torch being used to cut a steel pipe. Oxy-acetylene Welding (OAW) station. Oxy-fuel welding (commonly called oxyacetylene welding, oxy welding, or gas welding in the United States) and oxy-fuel cutting are processes that use fuel gases (or liquid fuels such as gasoline) and oxygen to weld or cut metals.

What is a rose bud torch?

A rose bud torch is used to heat metals for bending, straightening, etc. where a large area needs to be heated. It is so-called because the flame at the end looks like a rose bud. A welding torch can also be used to heat small areas such as rusted nuts and bolts.

How thick can a torch cut steel?

Tests showed that an oxy-gasoline torch can cut steel plate up to 0.5 in (13 mm) thick at the same rate as oxy-acetylene. In plate thicknesses greater than 0.5 in (13 mm) the cutting rate was better than that of oxy-acetylene; at 4.5 in (110 mm) it was three times faster. Operating cost for a gasoline torch is typically 75-90% LESS than using propane or Acetylene.

What are the disadvantages of acetylene?

As a fuel acetylene's primary disadvantage, in comparison to other fuels, is high cost. As acetylene is unstable at a pressure roughly equivalent to 33 feet/10 meters underwater, water-submerged cutting and welding is reserved for hydrogen rather than acetylene. Compressed gas cylinders containing oxygen and MAPP gas.

What is an acetylene generator?

Acetylene generator as used in Bali by reaction of calcium carbide with water. This is used where acetylene cylinders are not available. The term 'Las Karbit' means acetylene (carbide) welding in Indonesian.

What happens when the cutting nozzle is too large?

The height of the cutting nozzle is too large, the heat loss increases , and the preheating flame on the front edge of the incision of the heating effect is weakened, preheating is not sufficient, cutting oxygen flow energy decreases, making it difficult to remove slag, affecting the quality of cutting.

What is the purpose of a preheating flame?

The role of the preheating flame is to heat the metal workpiece to the temperature at which the metal burns in oxygen and to maintain this temperature at all times, while also stripping and melting the oxide on the steel surface to facilitate contact between the cutting oxygen stream and the metal.

What is the role of cutting oxygen flow?

The cutting oxygen flow plays a leading role. The cutting oxygen flow both burns the metal and blows the oxides generated by combustion away from the kerf. Therefore, the purity, flow rate, flow rate and shape of the cutting oxygen flow have an important influence on the flame cutting quality and cutting speed.

Why does a flame turn black?

When there is too much acetylene excess, it starts to smoke black, which is caused by the lack of oxygen necessary for acetylene combustion in the flame. The size of the energy of the preheating flame is quite closely related to the cutting speed and the quality of the kerf.

What happens when you increase the speed of a torch?

If you increase the torch running speed, the spark beam will be shifted in the opposite direction, when the spark beam is parallel to the cutting oxygen flow or slightly in front of the discharge, the cutting speed is considered normal. When the speed is too high, the spark beam is obviously backward.

What happens if oxygen pressure is too high?

If the cutting oxygen pressure is too high, the cutting seam will be too wide and the cutting speed will be reduced, which will not only waste oxygen, but also make the surface of the incision rough, and will also have a strong cooling effect on the cut parts.

What is the reduction zone?

The reduction zone is outside the flame core, and the obvious difference with the flame core is its darker brightness. The reduction zone consists of the products of incomplete combustion of acetylene – carbon dioxide and hydrogen, the temperature of the reduction zone can reach about 3000 ℃.

What are the different types of oxy-acetylene flames?

There are three basic types of oxy-acetylene flames viz., carburising or reducing flame, neutral or balanced flame and an oxidising flame. Apart from the chemical nature, these flames also differ in structure and shape. The carburising or reducing flame has excess of acetylene and is char­acterised by three stages of combustion instead ...

What is oxidising flame?

It is most often used for welding of low carbon structural steels and aluminium. The oxidising flame has an excess of oxygen over the acetylene. It consists of a very short pointed white inner cone and a shorter outer envelope. Such a flame makes a loud roaring sound.

What is the hottest flame?

Such a flame may oxidise the metal in the weld pool producing a weld bead with scummy or dirty appearance. An oxidising flame is used for welding copper base alloys, zinc base alloys and a few of the ferrous metals such as manganese-steel and some of the cast irons.

What is the additional combustion stage called?

The additional combustion stage is called the inter­mediate feather that can be adjusted by controlling the flow rate of acetylene. Such a flame is usually quoted by the length ...

How old is flame cutting?

The process is now about 111-112 years old as it was patented in 1901 by Thomas Fletcher.

What temperature is steel oxidized?

The process for all thicknesses is the same and that is the material must be “preheated” to a temperature of 1,600-1,800 degrees F, then the pure Oxygen is discharged into the preheated area and the steel is then oxidized or burned, hence the term “burning”. (The term “burner” is often used for the operator.)

What is the purity of oxygen?

The pure oxygen requirement is of a 99.5% minimum purity , which is the minimum purity typically provided in cylinders and bulk systems.

What thickness can be cut?

What thickness material can be cut? The process can cut from sheet metal thicknesses to 100 inch material. Prior to 1958, when Plasma was introduced, all thicknesses were flame cut. Today metal thinner than 3/8-1/2 are typically only cut by plasma or laser, as thin materials are very challenging to flame cut.

What does a reduction in purity of 1% mean?

A reduction in purity of .1% will reduce cutting speed about 10%, so one can see the necessity for the purity. While the source of the Oxygen may be pure, improper connections, bad hoses, or leaks of any sort can allow impurities in the system thereby reducing the cutting speed.

Overview

Types of flame

Uses

Apparatus

Fuels

The role of oxygen

Safety

See also