High pressure gas cylinders and rules for use

1、 Use of gas cylinders

① The cylinder needs to be connected with the pressure regulator, and then flows out for use after depressurization. Do not directly connect the cylinder valve to use gas. Regulators and piping of various gases shall not be used in a disorderly manner. Pay special attention to this problem when using oxygen, otherwise explosion may occur. The accessories and gas cylinders shall be painted with signs of the same color.

② Install the regulator, piping, etc. with a suitable one. If it is not suitable, it is not allowed to force the fitting. It is strictly prohibited to put lubricating oil on the joint and weld. After installation, the interface can be tested with foam water, and it can be used only when there is no air leakage.

③ Keep the valve clean to prevent sand, dirt or sewage from invading the valve casing and causing air leakage. During cleaning, an experienced person should slowly open the valve and discharge a small amount of air to flush away the dirt. The operator should stay away from the cylinder valve.

④ Open the valve slowly; When closing the valve, it is enough to stop the flow of gas, and do not use excessive force.

⑤ The cylinder of flammable gas shall be installed with one-way valve after passing through the pressure regulator to prevent flashback.

⑥ The gas cylinder shall not contact with the electrical wires to avoid electric arc, which may heat the gas in the cylinder and cause danger. If acetylene gas is used for welding or cutting metal, keep the gas cylinder away from fire sources and slag.

⑦ Before ignition, ensure that the air is exhausted and no flashback occurs before ignition. To this end, use a test tube to collect gas for test. If it is hydrogen, the gas collected will not explode before ignition. When using acetylene welding gun, it is also necessary to let off gas for a while to ensure that the air is not mixed before the welding gun is ignited.

⑧ Flammable gas or corrosive gas, it is recommended to remove the connecting pipe with the instrument after each test, and do not connect it overnight.

⑨ The gas in the cylinder cannot be used up, that is, the pressure of the input gas pressure gauge should not be zero, otherwise, it may be mixed with air, and the re loaded gas may be dangerous in the future.

⑩ A suitable fire extinguisher is required near the gas cylinder, and the workplace is well ventilated.

2、 Special attention and accident handling

① Copper salt and silver salt of acetylene are explosives. Acetylene gas and cylinder shall not contact copper or alloy containing more than 70% copper. All accessories shall not use these metals.

② There should be a safety bottle between the gas cylinder and the instrument to prevent the drugs from being sucked back into the bottle and causing danger.

③ In case of flashback or cylinder body heating, the cylinder valve shall be closed immediately, the cylinder shall be moved out of the outdoor open space, and the cylinder shall be immersed in cold water, or poured with a large amount of cold water to reduce the temperature, the valve shall be opened slowly, and the cylinder shall be kept cool until the gas is discharged.

④ Acetylene, hydrogen and petroleum gas are very dangerous flammable gases.

⑤ Although oxygen is not flammable, it has strong combustion supporting property and cannot contact with dirt and organics.

⑥ When corrosive gas is used, cylinders and accessories should be checked frequently, and should not be put in the laboratory when not in use.

3、 The purpose and operation of the pressure regulator The pressure regulator is an accurate instrument. It is designed to reduce the output pressure of the gas cylinder to a safe range before it flows out, so that the outflow gas pressure is limited to a safe range to prevent any instrument or device from being damaged by overpressure. At the same time, the gas flow pressure is stable. A good pressure regulator should have the following properties:

① The input gas of the cylinder changes the pressure, and the output gas pressure of the regulator can maintain the normal pressure.

② The pressure regulator does not change the pressure due to the change of gas output speed, and the deviation is very small, and the pressure is basically maintained at a constant value.

③ When the operation is stopped, the final pressure in the system will not increase.

4、 Operation method

① Before connecting with the gas cylinder, check whether there are foreign matters at the inlet of the regulator and the outlet of the gas cylinder valve. If there are foreign matters, remove them with a cloth. However, if it is an oxygen cylinder, it cannot be wiped with a cloth. At this time, open the cylinder valve slowly and carefully to blow out the dirt. Clean the dirty oxygen pressure regulator inlet with carbon tetrachloride or trichloroethylene, blow it dry with nitrogen, and then use it again.

② Use flat pliers to tighten the connection between the cylinder outlet and the regulator inlet, but do not force the thread. Some gas cylinders should be padded with sealing pads between the inlet and outlet. When using PTFE pads, do not use too much force, or the pads will be squeezed into the valve opening to prevent gas from flowing out.

③ Loosen the pressure regulating screw counterclockwise until there is no tension, and then close the regulator.

④ Check whether the needle valve of the output gas is closed.

⑤ When opening the gas cylinder, slowly open the valve of the cylinder and read the full pressure of the cylinder from the input meter. When opening, the valve needs to be fully opened, so that the output pressure of the regulator can be kept constant.

⑥ Turn the adjusting screw clockwise to adjust the output pressure to the required working pressure.

⑦ Adjust the needle valve to adjust the flow rate.

⑧ Close the cylinder valve first when closing the gas.

⑨ Open the needle valve to exhaust the gas in the pressure regulator. At this time, the readings of both pressure gauges should be zero.

⑩ Loosen the adjusting screw counterclockwise until there is no tension, and close the regulator.

(11) Close the needle valve output by the regulator.

5、 When the pressure regulator is not used, it shall be removed in time and saved as per the following method.

① The pressure regulator shall be kept in a clean place without corrosive gas.

② Regulators for corrosive or flammable gases shall be flushed with dry nitrogen immediately after use. When washing, open the screw clockwise, connect nitrogen and enter the inlet pipe. Rinse for more than ten minutes.

③ Then seal the inlet pipe with the original plastic bag to keep it clean.

6、 Check the pressure regulator frequently, especially the regulator with strong corrosive gas, once a week after use, and once every two months for others. The intact pressure regulator shall meet the following technical conditions:

① When there is no pressure, the readings of both gauges should be zero.

② Open the cylinder valve and read the higher pressure of the cylinder after loosening the screw.

③ Close the input needle valve of the regulator. Within five to ten minutes, the pressure of the output pressure gauge should not rise, otherwise there is an air leak in the internal valve.

④ Turn the adjusting screw clockwise to indicate the normal output pressure. If it cannot be reached, it means there is a blockage inside. Later, the output pressure will rise, which is called slow phenomenon. The regulator with slow phenomenon cannot be used.

⑤ Close the cylinder valve, and the input and output pressure should not change within five to ten minutes. If it drops, it indicates that there is air leakage at the input pipe, needle valve, safety device diaphragm, etc.

⑥ During operation, the output pressure drops abnormally, indicating that there is a fault in the meter. In case of any abnormality, it can only be used after being repaired. Note: Any gas pressure regulator cannot be used as an oxygen pressure regulator after use! In principle, each gas regulator cannot be mixed.

Article source: small carbon dioxide cylinder manufacturerhttp://www.chameto.com/