So many knowledge points about the air compressor tank!

Knowledge about the air compressor tank!

The main function of the air storage tank in the air compression system is to ensure the stability of the air supply. The compressed air deposits water in the air storage tank adjusts the air pressure fluctuation of the pneumatic equipment due to the unbalanced air consumption, increases the pressure stability of the air equipment, or reserves a part of the compressed air so that the user can use it when the air compressor fails. This part of the compressed air is used for the emergency treatment of pneumatic equipment or pneumatic control systems.

Selection of gas storage tank

1.Pressure selection

According to the pressure of the gas storage tank, it can be divided into a high-pressure gas storage tank, low-pressure gas storage tank, and atmospheric gas storage tank. The pressure of the optional gas storage tank is only required to be greater than or equal to the exhaust pressure of the air compressor, that is, the pressure is 8 bar, and the pressure of the gas storage tank is not less than 8 bar;

2.Volume selection

The volume of the optional air storage tank is about 0.3-0.5 of the air compressor displacement; if the environmental conditions permit, you can choose a large-volume air storage tank, which helps to store more compressed air and better Pre-water removal.

e.g.: If the air compressor displacement is 1 cubic meter per minute, the pressure is 8 kilograms. According to the calculation formula for the selection of the air storage tank, the volume of the air storage tank = the range between the displacement of the air compressor * 0.3 or the displacement of the air compressor * 0.5, (not less than one-third of the displacement One or one-fifth), a gas storage tank with a volume of 0.3 cubics or 0.2 cubics is recommended; if the gas consumption still needs to be increased in the future, the volume of the gas storage tank can also be appropriately enlarged, such as 0.5 cubic or 0.6 cubics, Or 1 cubic meter, etc.;

3.Material selection

The gas storage tanks can be divided into carbon steel gas storage tanks, low alloy steel gas storage tanks, and stainless steel gas storage tanks according to the different materials selected. They are used in conjunction with air compressors, refrigeration dryers, filters, and other equipment to form industrial production. Compressed air station on the power source. Most industries choose carbon steel gas storage tanks and low-alloy steel gas storage tanks (the yield strength and toughness of low-alloy steel gas storage tanks are higher than that of carbon steel gas storage tanks, and the price is relatively higher); stainless steel gas storage tanks Tanks are mainly used in the food industry, medical and pharmaceutical, chemical industry, microelectronics and other equipment and parts industries that require high comprehensive performance (corrosion resistance and formability). The user can choose according to the actual situation.

The service life of the gas storage tank

The gas storage tank is special equipment, and the manufacturer will give a recommended service life, which is basically 10 years at present. This does not mean that gas storage tanks that are more than 10 years old cannot be used. If they are more than 10 years old and have been submitted to the Quality Supervision Bureau for inspection every year, they can also be used. However, it cannot be used if it has been used for less than 10 years but fails to pass the inspection. The specific inspection results of the Quality Supervision Bureau are used to determine whether it can be used. It is recommended to use regular large-scale well-known brand gas storage tanks.

Generally, less than 1 cubic, 10bar (including 10bar), all belong to simple pressure vessels and are exempt from national inspection. Simple pressure vessels are indicated on the nameplate of the gas storage tank and the product quality certificate. They can be exempted from inspection within 7 years of validity, and registration is not required. The accessories are inspected according to the regulations of the local quality supervision bureaus.

For gas storage tanks of more than 1 cubic meter and 10bar above, you need to go to the local quality inspection office to apply for inspection. Not only you need to apply for a special equipment use registration certificate, but also a unit with installation qualifications can install it.

The difference between the gas tank connection port

There are two connection methods for the air inlet and outlet of the gas storage tank, one is thread and the other is the flange.

1. Threaded connection

The threaded interface is a thread-tooth type, which is suitable for connections with a relatively small diameter. Rp is the unit, and Rp means internal thread. For example, Rp1/2 means that the screw interface of the gas storage tank is one and a half inches of internal thread, and Rp2 is two inches of the internal thread. The dimensions of the threaded interface are: 1.5 inches, 2 inches (DN65)

2. Flange connection

The flange unit is DN, which refers to the nominal diameter of the pipe, also known as the nominal diameter. For example, DN50 is the nominal diameter of 50mm. When connecting, fix the pipe on different flanges, add flange gaskets in the middle, and then Then use bolts to connect the two flanges together, the flange connection is convenient to disassemble, and the sealing effect is better than that of the thread. Generally, flange connections are used for larger diameters. The dimensions of the flange interface are: DN80, DN100, DN125, DN150, these are conventional, and there are non-standard ones, such as DN200, DN300, which are non-standard.

Not all specifications of gas storage tanks have threaded and flanged interfaces, and there is no specific basis for choosing flange or threaded interfaces, mainly depending on the size of the air compressor interface.

Use of gas tank safety valve

As an important accessory on the gas storage tank, the safety valve of the gas storage tank often plays a key role for the entire system. Due to its particularity, the safety valve needs to be adjusted by professional operators. Before use, relevant inspections are required. During the inspection, follow the steps below in sequence:

1) First, cut off the gas supply source;

2) Provide water supply, start to check the operation status. Observe the pressure gauge. If the safety valve does not open under a certain pressure, further adjustment operations are required: continuously adjust the bolt position to achieve a more appropriate opening position. Through continuous inspection and adjustment again, this cycle is repeated to ensure that the safety valve can be opened normally.

The gas storage tank should be strictly in accordance with the gas storage specifications during use, the safety valve and pressure gauge must be installed correctly, and the inspection must be submitted every year (the actual situation is subject to the requirements of the local quality supervision bureau), if there is no way to produce If you stop, you have to spare one set, and there can be no fluke. In any case, safety is always the first priority.

Precautions for the use of gas storage tanks

1. The gas storage tank is strictly prohibited from over-pressure and over-temperature, and the operator should ensure that the gas storage tank is in normal working condition;

2. It is strictly forbidden to use an open flame around the gas storage tank or on the container, and it is forbidden to use an open flame to inspect the inside of the container. When the gas storage tank is under pressure, no repairs, hammering, and other impacts on the tank body are allowed;

3. Oil-lubricated compressors must undergo degreasing and dewatering treatments. The oil content, water vapor content, solid particle size, and concentration grade of the compressed air must comply with the appendix of GB/T3277-91 "or your local government principle. Compressed air quality grade for general use" Only after the provisions of A can enter the gas storage tank;

4. In view of the contact between oil and air in the air compressor, once the temperature is too high, it is easy to cause spontaneous combustion of carbon deposits and oil explosion ignition mechanism (see GB10892-89 for details). The compressed air entering the air storage tank must not exceed the design temperature of the tank. In order to avoid excessive exhaust temperature, the air compressor must regularly check the over-temperature parking device, and regularly check the heat transfer surface (filter, separator, and cooler), and clean it.

5. For compressors with oil, all pipelines, containers (air storage tanks) and accessories between the exhaust port and the compressed air temperature of 80 degrees should be checked regularly. Any carbon deposits should be effectively removed (including the compressor cylinder head). Carbon deposits).

6. The use and maintenance of air storage tanks and air compressors must strictly comply with the "Fixed Air Compressor Safety Rules and Operating Regulations", "Displacement Air Compressor Safety Requirements" and "Process Compressor Safety Requirements".

7. If the user of the gas storage tank does not implement the above requirements and warning clauses, it may cause the gas storage tank to fail and cause serious consequences, please remember that the user!