I. Introduction to gas storage tank
The gas storage tank is the volume of compressed air and gas discharged by the storage compressor. The gas storage tank is conducive to eliminating the pulse of the exhaust pipeline. When the demand exceeds the capacity of the compressor, it can store and replenish the compressed air. The larger the volume of the gas storage tank, the longer the operating time interval of the compressor. Compressed air storage tanks are one of the most used equipment in the entire compressed air system. It is simple in structure and can stabilize the pressure of the pipe network system, remove some pollutants, reduce the frequent start and stop of the compressor, prolong the life of the compressor, and reduce energy consumption. It is an indispensable part of the compressed air system.
II. Classification and composition
The trachea diameter is less than 1/2in (1in=25.4mm) for threaded connection and flange connection above 2in. The drain valve can be converted into an automatic drain. For gas tanks with large volumes, human holes or cleaning holes should be set up for inspection or cleaning.
- The safety valve is a safety protection device. When used, its limit pressure can be adjusted, and its value is about 10% higher than the normal working pressure.
- The air entrance and exit should be equipped with gate valves.
- There should be holes or hand holes for convenience.
- There should be a pressure gauge indicating the pressure in the tank on the gas storage tank.
- There should be a receiver and valve for oil and water discharge at the lower end.
There are usually two types of gas storage tanks: vertical and horizontal. The use of hours air compressors can be combined with a gas storage tank, or each air compressor can be separately equipped with a gas storage tank. The gas storage tank should be installed on the basis. Usually, gas storage tanks can be supplied by compressor manufacturers.
III. The role of gas storage tanks in the air system
- The gas storage equipment has a certain capacity. The air compressor will generate gas at the beginning of its work. If all the gas enters the gas equipment as soon as it is discharged, it will cause the equipment to be unable to withstand the pressure and has been loading and unloaded all the time. It cannot work normally, so it is necessary to install a gas that can cache gas. The container and gas storage tank just solved this problem.
- The air compressor can also get better air quality without refrigeration accessories, because gas storage equipment can precipitate stains and moisture in the gas in the process of storing the gas, and can also reduce the temperature of the gas.
- It plays a “timed” role: under the set pressure, the gas storage tank will be filled with air, so that the air compressor can automatically shut down under a certain pressure, which can also save energy consumption.
- Under the condition that the gas storage tank regularly discharges moisture and debris, the hot gas can be cooled. In the process of transformation, a small amount of liquid can be exported first, which can better improve the working quality of the air compressor.
- During the operation of the air compressor, all kinds of noises will occasionally be heard, which is caused by the impact of the gas in the pipe, and the presence of the gas storage tank can avoid such sound, because it can store air. If a operating device makes such a sound, it means The gas storage tank of this device may fail.
IV. Emerging problems and ways to deal with them
However, in recent years, the news of accidents and even explosions in gas storage tanks has been heard, which seriously affects production and caused great damage to human property.
Causes of the gas storage tank accident
Design defects
Design defects. It is not designed in accordance with national standards and relevant specifications.
Material defects
Defects in the materials of gas storage tanks shall not be produced in accordance with the specifications.
Overpressure
Overpressure is one of the factors leading to the failure of gas storage tanks, and many factors can lead to overpressure. If the selection of the gas storage tank is unreasonable, the design pressure of the selected storage tank is lower than the exhaust pressure of the compressor, the safety discharge device of the compressor body fails, the safety valve of the storage tank fails, and the storage tank will be exposed to the sun for a long time, and it will be placed in the fire source area, etc.
Burn caused by perennial accumulation of grease
Most air compressors are oil lubricated compressors, which will enter subsequent equipment and pipelines with the compressed air. In long-term operation, due to the unclean air, impurity metal corrosion in the air, spoiled emulsified oils, etc. in the air will slowly form oil-rich precipitation along the whole exhaust channel. As a gas storage tank with buffer function, due to the slowdown of the airflow, these precipitation is very easy to accumulate in the gas storage tank, which can be It can trigger combustion.
Accidents caused by machine running oil
The combustion of a large amount of lubricating compressed air caused by the running of the screw air compressor is filled with a large amount of lubricating oil. Due to the rapid flow rate, the static electricity associated with it will also accelerate, and the possibility of these two factors coexist and cause accidents will be greatly increased. Once the static electricity is not effectively exported and the oil and gas concentration reaches the limit of the explosion, the energy generated by instantaneous discharge is enough to cause the rapid combustion of oil and gas in the system and cause an accident.
Vibration
The installation of gas storage tanks is not standardized, and the pipeline does not have effective measures to eliminate its vibration, which will cause the pipeline system to be subjected to additional fatigue loads, loosening or cracking. If it is light, the leakage is heavy, it will cause an accident.
Improper maintenance management
Due to the lack of safety awareness of operation managers, the lack of dedicated management of the equipment, the safety accessories are not checked regularly, the storage tanks are not cleaned regularly, and the equipment continues to be used beyond the design life.
How to prevent it?
Select qualified products
Users need to choose the products produced by professional pressure vessel manufacturers to implement whether the tank manufacturer has a corresponding design qualification, whether the manufacturer has passed the corresponding qualification, whether it has passed the relevant certification of the quality system of the quality system, and inquire whether it has received administrative penalties or litigation.
Choose the right product
By selecting a gas storage tank that matches the exhaust pressure of the air compressor to meet the needs of the production process, the design pressure selection of the tank is greater than or equal to the air compressor may reach the maximum exhaust pressure, and an effective safety discharge device is set up according to the specifications to ensure the safety of the equipment when it is overpressurized.
Prevent overpression
In addition to the reasonable installation of a reliable and effective safe discharge device for the gas storage tank body, the air compressor should have effective protection measures to stop supercharging when the system pressure reaches the rated value. The compressor body also needs to be equipped with a qualified and effective safety release device. If the pipeline system entering the gas storage tank is equipped with a pressure adjustment device, it needs to ensure that it can Rely on sexual and overpressure protection devices to jointly ensure that system overpressure does not pose a risk of accidents.
Control and elimination of pollutants in gas storage tanks
We can reduce the system risk by controlling the amount of combustibles and the ignition source: select a reliable quality compressor and use it under its rated working conditions; the compressor needs to strictly control the amount of lubricating oil; when it is found that the lubricating oil content of the compressor is rapidly reduced, or there is a large amount of oil discharge in the system, we need to Timely shutdown inspection; select a compressed air storage tank with a repair hole, and clean up the internal sediment regularly; control the exhaust temperature of the compressed air; because it is exported when it flows to avoid sparks caused by excessive electrostatic accumulation. Therefore, the pipeline system and storage tanks need to be reliably grounded in accordance with the design requirements to eliminate static The impact of electricity on the system.
Correct installation and vibration elimination of storage tanks and pipelines
Storage tanks and pipelines should be installed and fixed in strict accordance with the design requirements, and the installation location should be in the shade and away from the fire source.
Strengthen the management and maintenance of equipment
Strengthen the management and maintenance of equipment. Improve the safety awareness of operators, special personnel management of equipment, regular verification of gas storage tank safety accessories, etc., timely replacement of damage failures to ensure that the equipment is not caused by disease; regular pollutant cleaning; strict operation and recording in accordance with regulations can greatly reduce the occurrence of accidents. Safety accessories, pressure gauges and safety valves of gas storage tanks should be regularly sent to the inspection department for inspection, and safety valves should be inspected once a year, pressure gauges should be inspected semi-annually, and the relevant components should be replaced after they reach their service life.