How to really use oxyacetylene welding, how to use oxygen acetylene welding tools?

Turn on a little gas first, turn on the oxygen after ignition, then increase the gas, increase the oxygen to adjust the appropriate flame, turn off the oxygen first, then turn off the gas, and then turn on the oxygen after extinguishing it, so as not to turn off the gas switch tightly and the fire will burn in the gun.

1. Oxygen cylinders.

1. Oxygen cylinders should comply with the provisions of the "Gas Cylinder Safety Supervision Regulations" promulgated by the state, and technical inspections should be carried out regularly. Gas cylinders that have expired and failed to pass the inspection are not allowed to continue to be used.

2. During operation, the distance between the oxygen cylinder and the open flame or heat source should be greater than 5 meters.

3. It is forbidden to rotate the cylinder without a shockproof ring to prevent it from being knocked down by an object when used.

4. Before using the gas cylinder, the bottle valve should be opened slightly, and the dirt adhered to the bottle valve should be blown out and closed immediately, and then connected to the pressure reducer before use. Pressure reducer and pipeline, etc.

5. It is forbidden to use oxygen instead of compressed air to blow clean work clothes and acetylene pipes, or to use it as an air source for pressure testing and pneumatic tools.

6. It is forbidden to use oxygen to ventilate local welding parts.

7. It is strictly forbidden to empty the oxygen cylinder, and there must be no less than the gauge pressure in the cylinder.

2. Dissolve acetylene cylinders.

1. The filling, inspection, transportation and storage of dissolved acetylene cylinders shall comply with the provisions of the "Gas Cylinder Safety Supervision Regulations" promulgated by the State Administration of Labor.

2. The handling, loading and unloading, and use of acetylene cylinders should be erected and stable, and it is strictly forbidden to lie on the ground and use it directly.

3. When opening the acetylene cylinder valve, it should be slow, not more than one and a half turns, and only three-quarters of the turn should be opened under normal circumstances.

4. It is forbidden to place objects, tools or wrap hanging rubber pipes and welding and cutting torches on gas cylinders.

5. The flashback arrestor that meets the requirements of use must be used together, and each welding torch or cutting torch must be matched with an independent and qualified flashback arrestor. Inspect and clean the soot and stains remaining in the vessel once a month. In order to ensure smooth airflow and reliable operation.

6. It is strictly forbidden to empty the acetylene cylinder, and there must be no less than the gauge pressure in the cylinder.

3. The use of welding torches and cutting torches.

1. The welding torch and cutting torch shall meet the requirements of GB 5108 5110 "Welding Torch and Cutting Torch Equipment".

2. Before using welding and cutting torches, the technical properties such as injection suction capacity and air tightness should be checked. It also requires that the gas path is unblocked, the valve is tight, the adjustment is flexible, and the connection part is tight and does not leak.

3. Welding and cutting torches should be regularly inspected, maintained, repaired and replaced. It is strictly forbidden to use it with faults.

4. After burning loss and wear, it should be replaced with qualified parts that meet the standards.

5. It is forbidden to rub the mouth of the welding and cutting torch with the ground or other places to clear the mouth blockage in use, and the through needle can be used to gently dredge the welding and cutting torch when the air source is turned off.

The order of ignition valve opening is to open the acetylene valve first, then ignition, and then turn on oxygen. When operating, the rotation of the preheating oxygen valve should be carried out slowly, if it is too fast, the suction in the cutting gun will be suddenly strengthened, so that the amount of acetylene ** can not keep up, resulting in backfire. When extinguishing the flame at the end of the work, the cutting gun should first turn off the oxygen source, then turn off the acetylene and preheat the oxygen in turn.

The latest standard is "GBT 2550-2016 Gas Welding Equipment - Rubber Hoses for Welding, Cutting and Similar Operations": the color of acetylene hose is red, and the color of oxygen hose is blue.

Steps to use an acetylene welding tool:

1. Ignition: When ignition, open the acetylene valve first, ignite the acetylene and immediately open the oxygen regulating valve.

2. Adjust the flame: The flame that is ignited at the beginning is the filial piety carbonization flame, and then gradually open the oxygen valve and adjust it to a neutral flame.

3. Carry out welding.

4. Flame-out: When the workpiece is flame-out after welding, the acetylene valve should be closed first and then the oxygen valve.

Attention should be paid to when welding:

Tip inclination: A certain angle should be tilted between the welding tip and the workpiece during gas welding.

When welding, the metal is heated to a molten state, and then the welding wire is filled, the welding wire and the surface of the weldment are inclined by 20 ° to 40 °, and the welding nozzle and the welding wire should be crossed and evenly oscillated during welding to avoid welding defects.

When gas welding, hold the torch in your right hand and the wire in your left hand. The welding should be started by heating and melting the workpiece as soon as possible to form a molten pool, and the inclination angle of the welding nozzle should be 80° 90°.

During normal welding, the inclination angle of the welding nozzle is generally kept between 40 and 50 °, and the welding wire is rhythmically lit into the molten pool to melt.

When welding to the end of the weld, the tip inclination can be reduced to 20 °.

In fact, it is the principle that acetylene is fully burned in oxygen to produce high temperatures. The nozzle of the cutting gun is actually a tube-in-tube structure, that is, a thicker tube with a thinner tube in it.

The thick tube is filled with an oxygen-acetylene mixture, which ignites to produce a high-temperature jet that melts the metal at the nozzle, and the thin tube is filled with pure oxygen, which blows the molten metal away to form a slit.

Oxygen is about 21% of the air oxygen. Liquid oxygen is sky blue. Oxygenation is a blue crystal.

It is not very active at room temperature, and it is not easy to interact with many substances. However, it is very active at high temperatures and can be directly combined with a variety of elements, which is related to the electronegativity of oxygen atoms second only to fluorine.

How to use: 1. First open the acetylene valve of the cutting torch, ignite it, then turn on the oxygen, and adjust it to a neutral flame nozzle about 5 mm away from the cut object.

2. Acetylene and oxygen can increase the cutting speed.

3. There are generally three switches in the stool circle of the cutting gun, and the top one is the high-pressure oxygen switch, which is commonly known as the high-wind switch; Below the high wind switch is the gas mixture switch; The last one of the switches is the acetylene switch.

The order of use is:

Unscrew the acetylene gas switch first, and slightly unscrew the oxygen switch, after ignition, adjust the amount of oxygen to make the oxyacetylene flame a neutral flame, (that is, the amount of acetylene and oxygen is appropriate). When cutting, first use this oxygen flame to burn a certain point to be cut until it is red-hot, and then unscrew the high-pressure pure oxygen flow switch, so that the metal is violently burned and melted into a liquid in the oxygen flow, washed away, and then the cutting gun is moved along the line to be cut off the metal.

Equipped with several nozzles with different aperture sizes to cut different thicknesses of metal. The nozzle number has 1, and the larger the number, the thicker the metal will be cut. <>

Oxygen welding operation: 1. When starting and starting welding, the temperature of the weldment is low or close to the ambient temperature due to the beginning of welding. In order to facilitate the formation of a molten pool and facilitate the preheating of the weldment, the inclination angle of the welding nozzle should be larger, and the flame should be reciprocated at the welding place to ensure uniform heating at the welding place.

2. The movement of the welding nozzle and the welding wire during the welding process In order to control the heat of the molten pool and obtain a high-quality weld, the welding nozzle and the welding wire should be evenly and coordinatedly oscillated.

3. After the welding of the joint and the closing car section is paused, and the welding and welding are restarted at the weld stop, the overlapping part with the original weld is called the joint. When welding to the end of the weld, the process of ending the weld is called finishing.

4. The left welding method and the right welding method welding torch move from right to the left of the oak, which is called left welding method or left welding method; The torch moves from left to right, which is called right welding or right welding.

There may be several reasons why the oxygen torch does not produce acetylene:

1.No acetylene in the acetylene cylinder: The oxygen torch needs to be welded with a mixture of oxygen and acetylene, and if there is no acetylene in the acetylene cylinder or if it is not installed properly, then the mixture cannot be obtained.

2.Incorrect mixing ratio of oxygen and acetylene: Oxygen torches need to use the correct mixing ratio of oxygen and acetylene, otherwise the combustion reaction will not occur. Usually, the correct mixing ratio is one part oxygen and two parts acetylene.

3.Poor connection of oxygen and acetylene pipes results in too much or too little oxygen in one pipe, resulting in an incorrect ratio of gas mixtures.

4.Improper use of oxygen welding torch: such as the handle is not completely closed and closed, the oxygen switch is not turned off, the pressure in the gas box is insufficient, etc.

5.Other reasons: For example, the acetylene in the gas cylinder is contaminated by oxygen, the acetylene cylinder is damaged, and the pressure of the acetylene cylinder is insufficient, etc., which will also cause the oxygen welding torch to not produce acetylene.

It should be noted that the oxygen welding torch is a dangerous tool, and it is necessary to follow the operating procedures when using it to ensure safety and avoid accidents. If you are unsure about the reason why the oxygen torch is not working, it is recommended to stop using it and seek professional help.