How to cut thick metal with gas. Cutting metal with an oxypropane torch. Gas cutting equipment

Advantages and disadvantages
Necessary equipment
Preparation for work
Getting Started
The nuances of metal cutting
Precautionary measures

Compared to gas welding work, gas cutting requires much less skill from a person. Therefore, mastering a gas cutter is not so difficult. It is enough to understand how to do it right. Propane cutters are the most widely used in our time. They use propane and oxygen together, as their mixture gives the highest combustion temperature.

Advantages and disadvantages

The advantages of cutting metal with propane over other methods are obvious:

Gas cutting is used when you need to cut a rather thick metal or cut something according to patterns, when a curved cut is required, which simply cannot be done with the same grinder. A gas cutter is indispensable if it becomes necessary to cut a disk from thick metal or punch a blind hole of 20-50 mm.
The light weight and ease of use of the gas cutter is another indisputable advantage. Those who have worked with gasoline counterparts know how heavy, clumsy and noisy they are, they vibrate strongly, forcing the operator to make considerable efforts during work. Gas models are devoid of all these shortcomings.
In addition, cutting metal with gas allows you to work 2 times faster than when using a device with a gasoline engine.
Propane is much cheaper not only gasoline, but also other gases. Therefore, it is advantageous to use it for large volumes of work, for example, when cutting steel for scrap metal.
The cutting edge with propane cutting is slightly worse than with acetylene torches. Nevertheless, the cut is much cleaner than that of gasoline burners or a grinder.

The only disadvantage of gas cutters (including propane ones) is the limited range of metals that can be cut with them. They are only capable of low- and medium-carbon steels, as well as malleable cast iron.

It is not possible to gas cut high-carbon steels because their melting point is quite close to the flame temperature. As a result, scale is not thrown out in the form of a column of sparks with reverse side sheet, but mixes with molten metal along the edges of the cut. This prevents oxygen from reaching deep into the metal to burn through. When cutting cast iron, the process is hindered by the shape of the grains and the graphite between them. (The exception is malleable cast iron). Aluminum, copper and their alloys are also not amenable to gas cutting.

It should be recalled that grades from 08 to 20G belong to low-carbon steels, and grades from 30 to 50G2 belong to medium-carbon steels. In the designations of carbon steel grades, the letter U is always placed in front.

Necessary equipment

To cut metal with gas, you must have one cylinder of propane and oxygen, high pressure hoses (oxygen), the cutter itself and the mouthpiece of the right size. Each cylinder must have a reducer that allows you to regulate the gas supply. Please note that the propane tank has a reverse thread, so it is impossible to screw another reducer onto it.

The design of gas equipment for cutting metal from different manufacturers differs slightly. Usually they all have 3 valves: the first one is for supplying propane, followed by a regulating oxygen valve, after that a cutting oxygen valve. Most often, oxygen valves are blue, the same ones that open propane, red or yellow.

The metal is cut under the influence of a jet of hot flame, which is generated by the cutter. During the operation of the apparatus in a special mixing chamber, propane combines with oxygen, forming a combustible mixture.

The propane cutter is capable of cutting metal up to 300 mm thick. Many parts of this device are interchangeable, so the device, in case of breakage, can be quickly repaired right at the workplace.

It is very important to choose the right mouthpiece. When choosing it, it is worth proceeding from the thickness of the metal. If the object to be cut consists of parts of different thickness, which varies from 6 to 300 mm, you will need several mouthpieces with internal numbers from 1 to 2 and external numbers from 1 to 5.

Preparation for work

Before work, it is imperative to inspect the device to make sure that the cutter is fully functional. Then do the following steps:

First of all, hoses are attached to the cutting machine. Before attaching the hose, it must be blown out with gas to remove any debris or dirt that has got there. The oxygen hose is attached to the right-hand threaded fitting with a nipple and nut, the second hose (for propane) is attached to the left-handed fitting. Remember to check for suction in the torch channels before connecting the gas hose. To do this, connect the oxygen hose to the oxygen fitting, leaving the gas fitting free. Set the oxygen supply level to 5 atmospheres and open the gas and oxygen valves. Feel the free fitting with your finger to see if air is being sucked in. If not, you should clean the injector and blow out the channels of the torch.
Next, check the plug connections for tightness. If you find a leak, tighten the nuts or change the seals.
Do not forget to check how tight the fastenings of the gas reducers are and whether the pressure gauges are working.

Getting Started

We set 5 atmospheres on the oxygen reducer, 0.5 on the gas one. (Typically, the ratio of gas to oxygen is 1:10.) All torch valves should be in the closed position.

To work as a cutter on the gearbox, we set 5 atmospheres, on the gas - 0.5.

A cutter is taken, first we open a little propane (a quarter or a little more), set it on fire. We rest the cutter nozzle against the metal (at an angle) and slowly open the regulating oxygen (do not confuse it with the cutting one). We alternately regulate these valves in order to achieve the flame of the strength we need. When adjusting, we open alternately gas, oxygen, gas, oxygen. The strength (or length) of the flame is selected based on the thickness of the metal. The thicker the sheet, the stronger the flame and the greater the consumption of oxygen with propane. When the flame is adjusted (it turns blue and crown), you can cut metal.

The nozzle is brought to the edge of the metal, it is held 5 mm from the object being cut at an angle of 90 °. If a sheet or product needs to be cut in the middle, the metal should be heated from the point from which the cut will start. We heat up the upper edge to 1000-1300 ° depending on the metal (up to its ignition temperature). Visually, it looks like the surface has begun to “wet” a little. In time, warming up takes literally a few seconds (up to 10). When the metal ignites, we open the cutting oxygen valve, and a powerful narrowly directed jet is applied to the sheet.

The torch valve should be opened very slowly, then the oxygen will be ignited from the heated metal on its own, which will avoid the back blow of the flame, accompanied by popping. Slowly we lead the oxygen jet along the given line. In this case, it is very important to choose the right angle of inclination. It should first be 90°, then have a slight deviation of 5-6° to the side, reverse direction cutting. However, if the metal thickness exceeds 95 mm, a deviation of 7-10° can be allowed. When the metal is already cut by 15-20 mm, it is necessary to change the angle of inclination by 20-30 °.

The nuances of metal cutting

You need to cut metal at the right speed. You can determine the optimal speed visually by how the sparks fly. A stream of sparks at the right speed flies out at an angle of approximately 88-90 ° to the cut surface. If the flow of sparks flew in the opposite direction of the torch, it means that the cutting speed is too low. If the spark flow angle is less than 85°, this indicates an overspeed.

When working, it is always necessary to focus on how thick the metal is. If more than 60mm, it is better to place the sheets at an angle to allow the slag to drain, and do the job as accurately as possible.

Cutting thick metal has its own characteristics. You cannot move the torch before the metal is cut to full thickness. By the end of the cutting process, it is necessary to gradually reduce the advance speed and make the angle of inclination of the torch more by 10-15°. Stopping while cutting is not recommended. If the work was interrupted for some reason, do not continue cutting from the point where you left off. It is necessary to start cutting again and only in a new place.

After cutting is complete, first turn off the cutting oxygen, then turn off the regulating oxygen, and lastly turn off the propane.

Surface and shape cutting

Sometimes it becomes necessary to cut through the metal not through, but only to create a relief on the surface, cutting grooves on the sheet. With this cutting method, the metal will be heated not only by the flame of the cutter. The molten slag will also serve as a heat source. Spreading, it will heat the lower layers of the metal.

Surface cutting, like conventional cutting, begins with the fact that the desired area is heated to the ignition temperature. By turning on the cutting oxygen, you will create a metal combustion center, and by moving the cutter evenly, you will ensure the cleaning process along a given cut line. The cutter in this case must be positioned at an angle of 70-80 ° to the sheet. When applying cutting oxygen, tilt the torch, creating an angle of 17-45°.

Adjust the dimensions of the groove (its depth and width) with the cutting speed: increasing the speed reduces the dimensions of the recess and vice versa. The depth of the cut will increase if the angle of the mouthpiece increases, if the cutting speed decreases and the oxygen pressure (of course, cutting) increases. The groove width is controlled by the diameter of the cutting oxygen jet. Remember that the depth of the groove must be less than its width by about 6 times, otherwise sunsets will appear on the surface.

You can cut a figured hole in the metal as follows. First, we outline a contour on the sheet (when marking a circle or flanges, the center of the circle should also be noted). Before starting the cutting itself, punching holes should be done. It is always necessary to start cutting from a straight line, this will help to get a clean cut on the curves. You can start cutting a rectangle anywhere except at the corners. The last step is to cut the outer contour. This will help cut the part with the smallest deviations from the intended contours.

Precautionary measures

Cutting metal with gas involves some risk, so you must strictly adhere to safety rules. Let's start with protective clothing, which should include: a fireproof suit and leggings for hands with the same impregnation; a welder's mask made of non-flammable plastic with a headband; work shoes with high sides. It is also recommended to wear a respirator. Why breathe smoke and dust? All these measures were not invented by chance, and they should not be neglected. For example, a situation may arise when thick metal is not immediately blown through, and molten splashes will fall on you.

In the process of work, do not forget to follow the indication of the reducers on the cylinders. Remember that you should not start cutting if the hoses have cracks, tears or joints. Some craftsmen connect the joints with a tube made of aluminum or brass. However, it's better not to risk it. Please note that iron pipes cannot be used for this purpose categorically, since iron can spark.

The most important thing to know when working with gas torches: propane is flammable, while oxygen is oil hazardous. When oxygen comes into contact with any oil, an explosion will occur. To avoid trouble, do not touch the oxygen cylinder with oil-stained gloves or clothing. Do not leave oily rags nearby.

Remember that the cylinders should be located at a distance of 10 m from the workplace and 5 m from each other. All gas from the cylinder can not be spent in any way.

Sometimes in the course of work there are emergency situations. Don't get lost. For example, if your oxygen hose flew off the fitting or broke off during cutting, do not be alarmed. Usually fear arises from the fact that it happens unexpectedly and loudly. It is necessary to immediately shut off the propane supply on the cutter, then close both cylinders. It happens that when the flame is ignited and the cutter is adjusted, the flame suddenly disappears, emitting a pop. Simply close the torch valves and rekindle the flame.

Cutting metal with a gas cutter consists of two main stages:

at the first stage, the alloy is heated to the desired operating temperature. For this, a flame of a burning mixture of gas with oxygen is used;
on the second - the metal is burned in a jet of oxygen.

How to use a gas torch: ignite the gas and heat the metal

Cutting torch brand NORD-S

Before lighting the torch, make sure that all connections in the fitting are tight.

Next, the acetylene valve is opened on the cutter and oxygen is allowed to exit the mixing chamber. When it becomes audible that acetylene is slowly coming out, tighten the valve. The burner is ignited with a special tool.

Lighters

The lighter should be placed in front of the nozzle so that its inside touches the mouthpiece. The lighter creates sparks that will ignite the acetylene.

A small yellow flame forms in front of the mouthpiece. Using the gas supply valve, we increase the length of the flame to about 250 mm. We make sure that the torch starts at the very mouthpiece.

If the fire "jumps" or breaks away from it, then the gas supply should be reduced.

Slowly open the front oxygen valve. It is necessary to supply such an amount of oxygen that is necessary for the complete combustion of acetylene. When this happens, the fire will change its color from yellow to blue. Thereafter, the oxygen supply should be increased until the inner blue flame is reduced and compressed.

We continue to open the oxygen valve and increase the size of the torch until the length of its internal flame becomes slightly larger than the thickness of the material being cut. If you hear a sound similar to "sniffling", or notice that the blue flame has become unstable, then you should reduce the oxygen supply. It is reduced until the flame becomes stable, and inside a clear cone is formed.

The cutter is brought to the workpiece so that the inner flame touches its surface with the very tip. Heating is continued until a "puddle" of molten metal is formed at the point of contact. The tip of the flame should be held motionless at a distance of 10 mm from this "puddle".

Gas cutting for metal: shortened and lever from Nord-S

How to cut with a gas cutter (technology)

We gradually increase the stream of oxygen, which ignites the molten metal. If a violent process has begun, and the steel has caught fire, then you can gradually increase the oxygen pressure (until the fire cuts through the material through and through). If the reaction does not start (the metal is not heated), then oxygen should be added and heated.

We began to cut the metal and slowly move along the cut line. All processed products are blown away by the jet towards the rear side of the cutting area. If this flow slows down or returns, then reduce the cutting speed or stop and warm up the material.

For many years, mankind has been using metal products. Some of them require preliminary cutting for subsequent application of small pieces.

One of the ways to cut metal is gas cutting. The technology of this method has its own characteristics and equipment used.

Metal gas cutting used to be very popular in repair work. This cutting method was the main one.

The spread of the application of this method is justified by a number of features:

Expands the possibilities of cutting thick workpieces;
Does not require power from the mains;
High performance;
Ability to perform complex operations;
Manual and automatic operation.

This method allows processing carbon and alloy steels, titanium alloys, brass, cast iron, lead, bronze, and aluminum products.

Gas cutting can be classified into categories in relation to the nature of the cut:

Dividing - characterized by the implementation of a through cut, which divides the workpiece into the required number of parts;
Surface - involves the removal of the surface layer of the workpiece, forming the necessary channels, slots and other structural areas;
Spear cutting - involves burning the surface to be processed to obtain openings or blind holes.

Thus, the method makes it possible to prepare various metal parts and weld pipes of different diameters.

Technological stages

The gas cutting technology of metal consists of the following steps:

Heating of a metal workpiece with a heater to a temperature of 1100°C;
Introduction of oxygen flow into the treatment zone;
When oxygen comes into contact with a metal surface, ignition occurs;
Under the influence of ignition, the workpiece begins to “burn out”, forming the desired processing result.

The billet is heated under the action of a mixture of combustible gas and technical oxygen.

As a combustible gas, propane-butane composition, acetylene, natural, pyrolysis or coke oven gas is used. The most popular are acetylene and propane-butane composition.

In the process of ignition, an oxide formation reaction takes place. They are blown out of the working area by a stream of oxygen. Oxidation of the metal occurs only in the areas of action of the oxygen flow, which excludes the ingress of reaction products into the metal. For the continuity of the cutting process, it is necessary to provide a jet of preheating composition in front of the jet of oxygen.

It should be borne in mind that the melting temperature of the metal being processed must be greater than the ignition temperature in oxygen. Otherwise, the combustion of the metal will not occur.

And also the melting index of the resulting oxides should be lower than the corresponding indicators for the metal. This is justified by the fact that otherwise the resulting products will not leave the working area, but will remain on the surface of the workpiece. When choosing a workpiece, it is required to focus on the thermal conductivity of the metal. The lower it is, the easier it is to ignite.

Cutter - cutting device

The change of stages of the cutting process is provided by special equipment. It implies an appropriate stable construction for the stability and safety of the operations carried out. One of the main components is a gas cutter. There are also nozzles for welding and melting, used in conjunction with this equipment.

Cutting involves the accuracy of dosage and connection of the gas mixture with oxygen. And also this device provides a warming flame and the introduction of oxygen into the work area.

Well-known cutters are injection-type devices that work with steel up to 30 cm thick. This cutter connects the cutting and heating block. The heating unit includes valves responsible for supplying the gas mixture and oxygen. And also it contains an injection cell, a mixing chamber, a supply tube, an external mouthpiece.

The cutting block is formed by an oxygen cutting jet outlet pipe, a control valve, and an internal type mouthpiece.

The gas mixture and oxygen move into the cutter through different inlets. Oxygen moves into the injector and mouthpiece to create a cutting jet. After the injector, oxygen is supplied to the mixing chamber, where the gas is also directed through its inlet.

After mixing, the composition is in the mouthpiece, responsible for the formation of a heating flame. Gates allow changing flows.

Cutters can be divided according to the area of \u200b\u200buse into:

Manual - used for manual cutting;
Machine - find application on cutting machines and machines.

There are also non-injector cutters and tools for supplying combustible mixtures of different composition:

Acetylene;
Propane, butane and propane-butane;
Universal;
Cutters for natural gas;
Kerosene cutters - have an evaporator unit for making vapors of gasoline, kerosene and gasoline-kerosene mixture.

When you start using any cutter, its serviceability is first checked. The device is then purged with oxygen.

Applied equipment

Cutting metal with gas involves the use of many basic and additional devices. In addition to the cutter, gas cutting equipment consists of:

Reducer - used in order to reduce the pressure of the supplied gas to the required value. It has two pressure gauges for measurements at the inlet and outlet sections.
Pressure change tool.
Cylinders for gas and oxygen.
Connecting hoses.

The reducer provides pressure regulation and automatic maintenance of the achieved value at a constant value. The reducer can be formed by one or two chambers. If two chambers are present, the device rarely freezes, which affects the reliability and sequence of operations.

Cylinders are made of steel. The volume is 0.4-55 dm3. They are equipped shut-off valve. Depending on the composition present (oxygen or gas), valves of various designs are provided. In relation to the composition inside the cylinder, color differences and inscriptions have been developed.

In the case of cutting with the use of special machines, the stationary location of the equipment is implied. In this case, auxiliary devices are used:

Cutting table;
Mechanism for removal of formed slags and cuttings;
Workpiece movement system;
Ventilation system.

In addition, other gas collapsible and working posts are provided.

Equipment for metal cutting on a large scale includes component components:

Bearing part;
Cutter (can be one or more);
Driving device;
Remote Control.

On big manufacturing enterprises portable cutting machines are often used. The principle of their work does not differ from stationary devices.

Instruction

First, heat up the cutting area to a certain temperature. Keep in mind that for each type of metal there may be a heating value. Basically, it varies from 300 to 1300 degrees. The preliminary procedure will allow the oxidation of the metal in oxygen to begin. As a result, a flame of acetylene or substitute gases appears. After that, you can start up oxygen, which cuts the metal and immediately removes oxides. Make sure that the heating flame is continuous, for this it must be a jet of oxygen.

Choose, if possible, low-carbon steels with a substance content of no more than 0.3%. They are the easiest to cut. For high carbon metals, you will need to resort to cutting with the addition of special fluxes.

Pay attention to the flame, its length should depend on the thickness of the metal. Thus, a substance whose thickness exceeds 400 mm must be cut with a flame penetrating the entire depth, containing a large amount of acetylene. Otherwise, you can do with the supply of a normal flame.

Set the direction of the flame to the edge of the metal, it is very important from the very beginning the correct angle of inclination. Point the preheating flame at the edge of the metal until you reach the desired reflow temperature.

Follow the specific order of the metal cutting procedure if you want to saddle holes. In this case, first heat up the edge of the material, then turn off the flame, and only then start cutting oxygen. Open the valve on the torch very slowly so that the oxygen flame is ignited by the melted metal and you avoid backfire, popping.

Pay attention to the thickness of the metal: if it exceeds 50 mm, keep the sheets at an angle, so you can ensure that the slag formations drain and do the job as accurately as possible.

Choose a mouthpiece based on the thickness of the metal: if it varies between 8-300 mm, you will need a mouthpiece with an outer 1 to 5 and an inner 1 to 2.

You will be able to correctly carry out the process of cutting metal, initially choosing the correct angle of inclination of the torch during cutting, determining the point from which you will start cutting, maintaining the correct flame angle (no more than 5 degrees of inclination, with a metal thickness of more than 100 mm, a deviation of 2-3 degrees is allowed ), choosing the right gas and a suitable mouthpiece.

note

The whole process must be carried out in special clothing. It is necessary to protect your eyes with special glasses, wear gloves and a suit.

Useful advice

When you complete the process, turn off the gas cylinders gradually. Eliminate the oxygen supply first, then the propane.

Sources:

how to cut metal

A paper cutter is an essential attribute of any printing house and almost any office. And the selection of these products in stores is impressive. However, choosing the right model for yourself is a very difficult task. There are roller cutters, reciprocating cutters, guillotine cutters - these are the three main types. Unfortunately, not all buyers of paper cutters are satisfied with the choice. And all because they look primarily at the price, not paying attention to more important selection criteria. To make a choice, first find out what you have to choose from.

Instruction

Roller cutters are the simplest and most affordable. The cutting surface is a sharpened metal disk that moves over the counter knife along the base of the device along the bar. In cheap models, the edge of the base often acts as a counter knife. Roller cutters can handle large format paper and are famous for their great accuracy. As you can see, such models are quite simple, so they are also very reliable and easy to operate. Their only drawback is low performance.

Reciprocating cutters are more productive than roller cutters. In them, as the name already implies, a sharp knife is used for cutting - a “saber”. On one side it is attached to the base of the cutter, and on the other there is a handle. By pressing it, you move the knife down, and it comes into contact with the counter-knife, the role of which can also be played by the edge of the base.

If at a time on a roller cutter you can cut an average of no more than 10 sheets, a reciprocating cutter can already handle 50 sheets of paper. Unfortunately, reciprocating cutters have more disadvantages than their roller "brothers": often the bottom sheets are cut along a curve, since the knife cuts the paper behind itself; paper fluffs up when cut, which leads to the formation of teeth on its edges.

To level these, you do not need to save on a reciprocating cutter - make sure that it is equipped with a reliable clamping device and a knife made of high quality steel. By the way, for the most part, the cost of a reciprocating cutter is determined by the knife.

For guillotine cutters, some unknowingly give out saber cutters. Undoubtedly, they are somewhat similar, but there are much more differences between them than similarities. Guillotine cutter models are equipment for professionals. They are able to cut a stack of paper several tens of centimeters thick. In addition to paper, guillotine cutters can cut other materials, both similar in structure to paper, and very different. And they usually buy such machines in printing houses and large offices. The equipment is, of course, not cheap. However, if you decide to get such a cutter for your printing house, buy at least one more roller - it can still do a job for which its guillotine "cousin" is not intended.

Office cutters are suitable for most standard operations. Therefore, they are widely used in small and medium-sized offices, as well as at home (by amateur photographers, for example). These cutters include most roller cutters, as well as some reciprocating models. The class of cutters is characterized by low productivity and low price. Remember, however, that if the price is too low, most likely the knife is made of low-quality metal, and you should not buy such a cutter.

Finally, professional cutters are devices that are primarily designed for printers. They can be not only guillotine, as some people think. Both roller cutters and reciprocating cutters, certainly equipped with very high-quality knives that provide an impeccable cut, may well be professional. These cutters are very reliable and have the highest performance. And, of course, they also differ in impressive prices.

Description

A dummy knife is great for making decor. The tool cuts regular paper, watercolor paper, pastels, and cardboard.

A knife consists of a handle made of wood, plastic or metal, and a blade. On sale you can find different models of tools that differ precisely in the shape of the blades. She may be:

with a pointed and serrated edge;
triangular;
rectangular;
sawtooth;
rounded.

Pointed blades have a sharpening angle of 30°. For triangular, this parameter is 23 °. Such blades can also be used when working with wood, plastic.

How to choose a mock knife

When choosing a dummy knife, pay attention to what material its handle is made of. It is recommended to purchase a tool with a metal handle. The plastic handle should be strong enough not to break under pressure. It is better that there is a seal on the handle, it does not allow the hand to slip off.

Another nuance is the blade clip, which is a metal knob covered with rubber. If it is made of plastic, it is better not to buy such a tool. It is not reliable, after a while a gap may appear in the mount, and the blade will fall out.

How to use a craft knife

Carry out cutting with a breadboard knife in the following order:

Draw the outline of the image from the wrong side of the material.
Start cutting with the smallest details. Move on to the center section. If there is a contour, process it last.
Cut through all the details, leaving none. In no case should you pull out any of them, this will spoil the work.
Use a ruler to make it easier to cut straight lines.
In the process of work, you can rotate the material with a pattern. This will make the job easier.
Choose a suitable background depending on the chosen plot, the purpose of the cutout and glue the work on it.

For safety reasons, do not give the dummy knife to children, let them use scissors. Use a mock-up mat for your work. It will allow the blade of the knife to stay sharp longer. At first, you can replace the mock-up rug with a stack of newspapers, a cutting board, a piece of linoleum, or glass.

Modern works made by cutting out of paper are called openwork (filigree) cutting, as well as paper graphics, cut-out images. Using this technique, you can make napkins, postcards, panels, frames, window decorations, mirrors, etc.

So, gas cutting of metal is now the most popular. Why?

Because it is extremely simple to perform, you do not need to use any phase inverters (as in an electric cutter), you do not have to comply with the mandatory room standards (the presence of a central ground cable).

And almost all gas cutters are mobile, that is, they can be transported by conventional transport.

When cutting, a gas cutter uses two gases - directly oxygen, with the help of which the metal separation process is performed, as well as a heater, which is most often propane or acetylene.

The heater heats the surface to be cut to a temperature of 1000-1200 degrees, after which a jet of oxygen is supplied. From contact with a heated surface, the jet ignites.

It turns out - a burning jet that easily cuts the metal. At the same time, the most important thing is to maintain a continuous supply of oxygen.

If there is an interruption, then the flame can simply go out, after which the surface will again have to be heated.

Standard oxygen cutting of metal is performed using the R1-01P cutter. It is best suited for working with hardened steel, including cast iron!

As welding machine this cutter is not used.

But it is suitable for precise pipe cutting - for this, a special RF7 hinge plate is used, which is made of steel, but covered with a layer of tungsten.

By the way, recently, metal cutting has also been performed using a combination of acetylene and propane. But such equipment is used exclusively for working with high-strength metals (for example, steel for copulation knives).

Equipment that supports operation with such gas is not cheap! So we won't talk too much about it...

The modern technology of gas cutting of metal is somewhat different from the one described above. For example, to work with light metals» Temperatures of 1000 degrees Celsius and above can simply destroy the metal you are working with (melt and vaporize).

In these cases, the cutting itself is performed with simultaneous heating. The tip of the cutting torch is in the form of a pyramid with 3 nozzles.

A heating mixture is supplied through two lateral ones, and a thin nozzle is mounted in the center for supplying oxygen under high pressure.

In modern cutters, oxygen is supplied under pressure of 12 atmospheres! Simply put, even the skin can be damaged under a stream of air (meaning an unlit stream).

The flux that is formed during such cutting is either thrown out by a preheating flame to the sides, or burned directly through the entire metal (if through cutting is performed).

Do not forget that gas cutting metal has a great advantage over electric. Which?

No "torn" seam is created. And if you additionally use overlays (stencils, as professional welders call them), then the cutting seam turns out to be very neat!

But keep in mind that cutting metal with oxygen does not mean using metals that melt at temperatures below 600 degrees Celsius. In this case, a simple removal of the top layer of metal will be performed, and not cutting it.

Standard technology oxygen cutting metal cutting involves using a guide cutter controlled by the operator. The gas supply is regulated by two valves (in some models - one common).

The cutter handle itself has two tubes that fit into the handle. The first handle supplies fuel for the heater, the second (usually the central one) supplies oxygen. That is, as many as 3 tubes are brought to the main nozzle!

Propane is supplied through two, oxygen is supplied through the third. Older torch models used two tips that worked in a similar way.

What is the gas consumption when cutting metal? It depends on the temperature to which the metal itself is heated during operation.

In a standard R1-01 cutter, on average, about 10 cubic meters of oxygen and 0.7 cubic meters of acetylene are consumed per hour of operation (when using propane - 1 cubic meter of fuel).

But in the R2-01 cutter, the consumption is much higher - 21 m3 of oxygen and 1.2 - acetylene! The heater consumption depends on the heating temperature and the plane being cut.

The "older" torches also use the so-called direction of the nozzles, which also partially affects the flow rate (the closer to the oxygen jet, the larger the jet has to be supplied).

Gas cutting equipment

So, in Russia, since the times of the USSR, the R1-01 cutter was considered the most common. It is hand-held with an injection nozzle that produces a high-pressure jet that cuts through metal "like a hot knife through butter".

More powerful models are R2-01 and R3-01P. Their main difference is the size of the nozzle, the working pressure of oxygen in the system, the working pressure of the supply of the heating mixture.

There are also stand-alone tables - this is gas equipment for cutting metal in automatic mode, which is produced without the participation of the operator.

Management of such a table is numerical-program. That is, a person simply sets the cutting parameters.

Such oxy-fuel cutting equipment is used exclusively on sheet metal, where either straight cutting or arc cutting is performed.

It is worth noting that there are a huge number of models of these tables, but almost all of them are analogues of the AN-01, which was developed by Shepelev back in the USSR!

These, for example, are "Change", "Orbit", "Secator", "Quicky-E". All of them have an operating temperature in the range of 1000-3200 degrees Celsius. Works with both acetylene and propane heaters.

The Quicky models also use mixed - acetylene-propane heating. In this case, only a bifurcated nozzle is used. That is, acetylene is supplied to one of them, propane to the second.

By the way, it is worth noting that in such cutting the heating mixture lends itself from the center (that is, from the oxygen jet).

The so-called stationary cutting torches for gas cutting of metal are also noted.

They differ from mobile ones, it is not difficult to guess, in that they are built into a special niche-machine, which the operator of the device can just move.

Such cutters are more convenient to work with, but are very expensive. But their cutting power is more than enough to cut through a thick layer of high-strength metal!

This became possible due to the fact that such cutters use an additional blower, with the help of which both the heater and the oxygen jet are supplied under even greater pressure.

The additional compressor works on electricity, besides - three-phase (380 Volts). Because of this, he cannot be mobile! This cutter is used exclusively in professional enterprises.

Portable cutter - Gugark

Gugark is the most popular representative of such cutters.

By the way, gas-burner for cutting metal, there are also two types - the so-called straight and bent:

The first is the one you are all used to seeing. It is the letter G and works with the help of the operator's direction.
Well, the second, straight one, is a nozzle-type burner, which is used on cutting tables.

It is also worth noting that straight nozzles use twin tips to ensure that the movement does not disturb the angle of inclination of the nozzle one to one.

By the way, keep in mind that each of the cutters has its own coefficient of work and power with each metal.

For example, when using the standard P1-01, a coefficient of 0.5 acetylene is enough to cut copper, but for aluminum it will take as much as 0.7.

Most of all, of course, will go to tungsten - as much as 1.4! In this case, the heating will be in the region of 3800 degrees Celsius (use only specialized tips)!

Services popular on the market

If you need to cut metal, then the easiest way is to hire a craftsman or specialist who will provide you with the necessary services. After all, not every house in the garage has a cutter with two cylinders of oxygen and a heater.

Moreover, it is very dangerous to work with such equipment without experience! If you don’t know how, then it’s better not to take on this matter - entrust the work to professionals!

Well, on average, the price of gas metal cutting consists of the following indicators: the metal with which it will be necessary to work, the cutter used, the thickness of the metal, the quality and type of cut.

For example, conventional sheet cutting is the cheapest. Pipe cutting is much more expensive, since additional overlays are used for such work!

But cutting into depth is an expensive pleasure, since it uses expensive equipment.

Moreover, if such work is performed "on the road", then it will be very expensive. Cars that can transport cutting stations need to be additionally converted.

Oxygen metal cutting - video:

Well, gas cutting sheet metal can be performed even with a conventional gas soldering iron. If you are using aluminum or copper, then it should be sufficient for the job.

In some cases, you can use gas welding. But instead of carbon dioxide, propane, acetylene or butylene is supplied (not every gas welding supports the use of such a gas, be careful)!

The most expensive sheet metal cutting is the one that is performed along the prepared cutting contour. In this case, a CNC machine is used, the services of which are not paid cheaply!

By the way, if you need to perform not cutting, but cutting, then in some cases it will be much easier and cheaper to use a knife for cutting metal, and not a gas cutter. You can learn more about this directly from the master to whom you want to entrust the work.

Now many enterprises offer gas cutting of metal on site.

Here it is, evaluated according to the following parameters:

metal with which it will be necessary to work;
the complexity of the work;
cutter used.

It also takes into account how much work will take time. On average, an hour of the master's work is paid at about 300 rubles. Here you can calculate in advance how much metal cutting services will cost you!

And finally, we should talk about those cases when poor-quality work is performed. Very often, many people use propane or propylene instead of acetylene - its cheap counterpart. Or they use cheaper cutters than they were declared by them.

For example, instead of P2-01, P1-01 or the like is used. By the way, this is the most common problem! You can tell the difference between the two cutters by visual inspection.

The P1-01 model has a double nozzle with a gold mount (golden color), while the P2-01 has a steel mount (has a black or copper tint).

By the way, the P1-01 cutter is not so expensive, so you can even buy it! The average cost is in the range of 900-1000 rubles apiece. Well, of course, it will be necessary to purchase two cylinders - with oxygen and a heater, and of course a transport cart.

On average, the whole set will cost you 3000 rubles, not more. It will be enough for 3 hours of metal cutting. For domestic needs, this is more than enough.

And when working with a gas cutter, be sure to follow the safety rules! And this is the use of a protective mask, overalls and gloves. Gloves are a must!

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