![<?echo $_SERVER['SERVER_NAME'];?>](/template/twentyseventeen/skin/images/header.jpg)
1 Vibration-induced gas tank damage example In the work, the author repeatedly found that the gas tank cracked due to pipeline vibration, not only delayed production, but also the safe operation of equipment. Two of them are described below.
Two air compressors in an aluminum plant are connected with a gas storage tank, and the air compressor exhaust pipe is directly connected with the air inlet pipe flange of the gas storage tank, and the exhaust pipe of another air compressor is outdoor and the first The air compressor pipe is connected at right angles, and the connection part is the pipe bend.
At the vicinity of the side leg of the gas storage tank, there is a trace of oil leakage. After inspection, it is found that the base material of the lower head is cracked and located at the edge of the leg. The outer length of the crack is 20, and the inner surface length is 23, 1. The crack is transverse. For example, the scoring ruler is that the horizontal air outlet pipe of the air compressor forms a lateral thrust to the gas storage tank, and the air flow pulsation bow vibrates from the gas storage tank to the left and right, resulting in lateral fatigue failure of the lower head at the side leg. Due to the influence of the secondary membrane stress in the internal pressure of the gas tank, the crack on the inner surface is longer than the outer surface.
Precautionary measures 1 Stabilize the foundation, lay the ground bolts and reduce the vibration; when manufacturing the 2 legs, increase the pad to eliminate the stress concentration.
2 Example of over-temperature explosion of gas storage tanks The over-temperature combustion explosion occurred in the gas storage tank of a certain factory oil compression connection, which poses a great threat to safety production. The reasons that may cause this situation are as follows: The reason for the strength of the gas tank shell depends mainly on the design temperature design type and manufacturing quality. The control of the actual equipment operating parameters and the safety status of the equipment will directly affect the safe operation and service life of the pressure vessel. If the design structure of the gas storage tank is unreasonable, the material is improper, the manufacturing quality is poor, and there are local defects such as uneven wall thickness and severe rust corrosion. Even if the gas storage tank is still working under the rated pressure, it will still explode due to insufficient local strength. The force container of the sulfonium pressure interface belongs to the special state establishment. The State Bureau of Quality and Technical Supervision issued the pressure vessel safety technical inspection procedures. The pressure vessel design, manufacture, installation, quality inspection, operation monitoring and maintenance management have strict regulations and must be strictly observed. Any negligence in any link may result in a serious explosion.
The cylinder lubricating oil of the reciprocating piston air compressor is mostly made of mineral lubricating oil, which is a kind of combustible material. When the temperature of the gas rises sharply and continues to rise after the flash point of the lubricating oil, it will violently oxidize and the bow will explode. Alternatively, an oil deposit will be formed along the entire exhaust system, abbreviated as carbon deposit. The carbon deposit causes a combustion explosion due to mechanical impact of the impact of the hard particles during the movement and the spark generated by the electrostatic discharge. Reasonably select the type and grade of cylinder lubricant, strictly control the amount of lubricant, do not use too much or too little fuel, should follow the equipment technical documents. Controlling the exhaust temperature is an inspection of the air compressor cooling system. If the cooling water quality is reasonably selected, the fouling of the cooler pipe wall and the cylinder water stave is removed in time, and the temperature difference between the inlet and outlet of the cooling water is controlled; the temperature of the gas in the pipeline gas storage tank is lowered and the maintenance is strengthened to ensure that the gas does not leak. Prevent gas circulation compression; it is a protection device for setting the temperature of the cooling water in the exhaust gas temperature storage tank at all levels, which can automatically cut off the power supply when it is over temperature; it is to strengthen the suction filtration to prevent the inhalation of gas and dust and contains hard particles. It is to strengthen the cleaning of the gas storage tank to prevent the carbon layer from being too thick; the sixth is to improve the sealing effect of the stuffing box. Prevent the oil in the crankcase from leaking into the cylinder and entering the gas storage tank.
The reason for the gas pressure in the gas tank is determined by the pressure regulator and Antao. Once, one person has a barrier. If the earthwork is mistaken, or the safety valve is inoperable or the pressure finger is inaccurate, the gas pressure in the tank rises sharply, and the container is exposed to heat such as sun exposure.
It also causes an increase in the pressure inside the container. If it exceeds the strength limit of the wall thickness of the tank, an explosion will occur. The pressure protection device inside the gas storage tank is set up, and the overpressure can automatically cut off the electricity. The pressure regulator safety valve must be properly commissioned to ensure flexibility and reliability. Operators must be familiar with and follow the safe operating procedures of air compressors and pressure vessels.
Causes of pipeline vibration and preventive measures Reciprocating piston air compressors due to modern trade, the extraction of microbial flocculants and the determination of active components. Zhang Weizhuo Boluo County Environmental Science Research Institute, Guangdong Huizhou 5 Introduction Flocculant, also known as sedimentation agent, as a class The substance which can make the solid suspended particles which are not easy to settle in the liquid coagulate and precipitate has a wide application in the fields of waste water treatment and fermentation industry, such as the treatment of civil engineering dredging of food processing.
The flocculants currently used can be classified into inorganic flocculant synthetic polymer flocculants and natural biopolymer flocculants from their sources and properties.
The inorganic flocculants are mainly iron-based ferric chloride ferric sulfate and its polymers and complexes such as aluminum chloride aluminum sulfate and its polymers. Aluminum salts are toxic and can affect human health, such as Alzheimer's disease; iron salts can cause color in treated water, such as high concentrations of iron can also adversely affect human health and the ecological environment. Synthetic high-molecular flocculants, such as polyacrylamide derivatives, polyethylene-polypyrimidine; hydrazine, in nature 1; easy to be, 4 caused secondary pollution, and its monomer has an effect on teratogenic carcinogenesis. Therefore, the application of these flocculants is greatly limited.
In contrast, natural biopolymer flocculants are harmless to the human body, can be biodegraded, and have no adverse effects on the ecological environment. They are far safer than the first two types of flocculants, and the microbial flocculants are natural biopolymer flocculants. An important category. Microbial flocculants are the most promising in bioflocculants because they have many types of microorganisms that can produce flocculants, and they grow fast and are easy to adopt bio-engineering methods to achieve industrialization.
Microbial flocculants are metabolic organisms with flocculation activity produced by certain types of bacteria, such as actinomycete yeast, under specific culture conditions, which are metabolized and metabolized to a certain stage. Microbial flocculants mainly include flocculants utilizing microbial cell metabolites and flocculants directly utilizing microbial cells using a flocculant of microbial article number 16723835 cell wall extract.
Microbial cells are an important source of natural organic polymer flocculants. The matrix of the algal cell wall is mainly composed of many heteropolysaccharide lipid substances and partial proteins. Alginic acid, which has been widely used as a flocculating agent, is a component of the brown algae cell wall. A component such as a dextran mannan protein of the yeast cell wall and acetylglucosamine can also be used as a flocculating agent. In addition to cellulose mannan and dextran, cell wall polysaccharides of filamentous fungi also have an extremely important polysaccharide chitin. The cell wall of bacteria also contains a variety of substances that can be used as flocculants, such as lipopolysaccharides and proteins in Gram-negative bacteria, phosphorus-wall proteins in Gram-positive bacteria, and acetylglucosamine and acetyl in peptidoglycans. Cell wall acid. However, due to the small number of bacterial cells, it is difficult to collect. At present, the cell wall extracts using algae and mold are more, and the bacterial cell wall is less.
Some of the metabolites of microbial cells are stored in cells, while others are secreted outside the cell. The substances secreted outside the cell are mainly the capsules and mucus of the bacteria. In addition to water, their main components are polysaccharides and small amounts of polypeptide protein lipids and their complexes. These substances can be used as flocculants to some extent, but the most important ones are polysaccharides.
The first flocculant is the direct use of living cells as a flocculant. It has the following advantages 2 to eliminate the cost of extraction; a small number of strains can be used to access the treated waste liquid for breeding; no secondary pollution. The deficiency is that there must be no factors in the treated waste liquid that hinder the growth of the bacteria.
The exhaust temperature of the stage is too high; the process of suction and exhaust of the air compressor is intermittent, so that the pressure and speed of the airflow in the pipeline are pulsating and periodically changing. Exciting force will be generated, and the bow will vibrate in the pipeline. As a result of the vibration of the pipeline, the joint between the pipe and the pipe or between the pipe and the valve cooler of the gas tank is subjected to repeated vibration stress, so that the pipe system is subjected to additional fatigue load, loosening may occur, and cracking may occur, and leakage may occur. However, it caused an explosion and caused an accident. When designing the compressed air pipe, the elbow valve and the reducer pipe should be minimized, or the radius of curvature of the pipe bending should be made larger to reduce the exciting force. Install the equipment in strict accordance with the design requirements. For pipelines that are in use and have been vibrating, a buffer can be placed very close to the compressor. If it is found that a certain section of the pipeline vibrates strongly, first determine the cause of the vibration of the bow 1. If it is not mechanical resonance, it can be solved by clamping or pressing a certain part of the pipeline or increasing the support of the pipeline somewhere, but it is necessary to choose the appropriate pipeline. Positioned.
Reason management is not in place and preventive measures are not strong in safety awareness. For special equipments with fixed risks, standard management is not implemented. Equipment bodies and safety accessories are not regularly inspected. Daily maintenance is ineffective, and multiple installation and use management of equipment is required. There are security risks in the link, which is the fundamental cause of the explosion.
Summarizing the above two specific accident case analysis, we can draw the following conclusions. If we want to ensure the safe operation of the pressure vessel and improve the stability of the system, we must do the following: 1 We must conscientiously implement the management specifications of the pressure vessel and Safety technical regulations. Execution, online inspection and periodic inspection, 21 regular inspection of the operation and maintenance of the container, the container defect treatment plan should be carefully formulated. 3 Reported to the higher authorities to strengthen the safety technical education and technical assessment of operators. Non-destructive testing of crack-prone areas is carried out on a regular basis, and defects are found to be disposed of as early as possible. 4 Strictly control the working pressure of the gas storage tank. Add and improve the vibration-reducing device for the inlet and outlet pipes, reduce the number of vibrations of the container, and do not allow overpressure and overload work. The newly used gas storage tanks are strictly inspected according to the requirements of the labor department. Not qualified, not installed. 5 pairs of found containers are defective, not free to repair. In case the defects are repeatedly generated or expanded. Strictly implement various rules and regulations, carefully operate, carefully fill in the operation record or production process record to ensure the safe operation of the production; when the air compressor system is abnormal, emergency stop measures should be taken and reported to the superior in time; any harmful equipment The violation of the command should be refused.
Meat Grinder Accessories,Meat Mincer Accessories,Meat Grinder Accessories Parts,Mincer Accessories
DONGYING SHENGYU METAL PRODUCT CO.,LTD , https://www.shengyucasting.com