With the rapid development of the industrial technology revolution, people pay more attention to product quality and environmental protection issues. Hydraulic technology has been widely used in the national economic sector, and the degree of hydraulic transmission has become one of the important indicators to measure the level of a country's industrial level.
Therefore, how to reduce the noise vibration of the hydraulic device, improve the working performance of the hydraulic system and improve the machining accuracy of the hydraulic cutting machine tool have become an urgent problem to be solved in various countries. Air entering the hydraulic system is one of the most common factors affecting the normal operating performance of the hydraulic system. Therefore, it is necessary to study the causes of air failures in the hydraulic system and to explore measures to improve and eliminate such adverse effects.
1 The influence of the hydraulic system entering the air on the hydraulic oil and the consequences 1. After the compressible air invades the oil, part of it is dissolved in the pressure oil, and part of it forms bubbles floating in the pressure oil. Because the air has compressibility, the hydraulic oil has obvious elasticity, commonly known as hydraulic spring, so the hydraulic transmission rigidity is generally lower than the mechanical transmission, and it is easy to produce low-speed mountain climbing or the worktable changes with load.
1. 2 Oxidative stability If the hydraulic oil is in direct contact with the oxygen in the air, it is prone to chemical reactions especially at high temperatures. After the oil is oxidized, acidic compounds, gelatinous precipitates, etc. can be formed, which can corrode the metal and prevent the system from neutralizing the pipeline and the valve port, thereby seriously affecting the working performance of the hydraulic system.
2 Intrusion of air to the hydraulic system produces vibration, noise phenomena and causes and analysis 2.1 Noise hazard Unfairness affects the hydraulic system and performance and life, and induces various faults, while giving the surrounding people a feeling of discomfort, in spirit and health It has an adverse effect on it. Air entering the hydraulic system is one of the main causes of noise. Therefore, it is important to study and analyze the reduction and elimination of hydraulics and noise.
2.2 Analysis of Henan Mechanical and first author College: Male, born in March 1969, BA, lecturer in general hydraulic oil at atmospheric pressure and room temperature, usually in the air can absorb approximately 9. The amount of air dissolved in the liquid is related to the amount of air pressure in contact with the surface of the liquid. When the pressure is lower than the separation pressure of the air of the oil at the working temperature, the air dissolved in the liquid is largely separated to form bubbles. If the formation pressure is extremely low and the saturated vaporization pressure of the oil is reached, the steam of the oil is precipitated together with the air to form a boiling phenomenon of the oil. With the operation, the air bubbles mixed in the oil are broken together, and local high-frequency surges are generated locally, sometimes up to 200 MPa or more with local high temperatures. On the one hand, this high-frequency hydraulic shock wave has a destructive effect on the metal surface of the component, causing so-called cavitation phenomena such as metal spalling and pitting, and on the other hand, the pump and other components produce large pressure fluctuations and are excited. High frequency noise. Figure 1 below shows the effect of air content on the noise in the oil. It is easy to see that the air content increases and the noise increases.
3 Causes and analysis of the creeping phenomenon caused by intrusion of air to the hydraulic system 3. 1 Crawling and its hazard crawling is a phenomenon that often occurs in hydraulic systems. For example, in metal cutting machines, unfair creep can affect the machining accuracy and surface roughness of the workpiece, and it can shorten the life of the mechanism or tool. Air intrusion systems are a major contributor to creep. It is therefore important that the cause of crawling and the elimination of creep are observed.
3. Reason analysis The following is an example of the hydraulic system crawling physical model shown in Fig. 2, which analyzes the mechanism of the crawling mechanism of the actuator in the hydraulic system.
If there is air in the hydraulic cylinder, the pressure oil type from the left chamber needs to overcome the large static friction between the table rail and the bed rail when starting the movement. At this time, the air bubbles in the left chamber are still compressed ( Figure 2a), the workbench does not move. When the pressure oil pressure in the left chamber increases, the bubble is compressed and the volume is reduced. (Fig. 2b) The table starts to move. At the beginning of the movement, the static friction between the table rail and the bed rail suddenly becomes dynamic friction, the force is reduced, and the left chamber pressure reduces the bubble expansion (Fig. 2c). The piston suddenly accelerates, that is, the table Fast forward. Due to the rapid advancement of the table, this aspect causes the bubble in the oil discharge chamber to be suddenly compressed and on the other hand to increase the oil discharge force, and as a result, the back pressure, that is, the right chamber pressure, is increased. That is to say, with the front rush of the workbench, on the one hand, the pressure in the left chamber is lowered, and on the other hand, the pressure in the right chamber is increased. Its comprehensive effect causes the workbench to be braked quickly after being flushed. When the pressure in the working chamber of the hydraulic cylinder rises again to overcome the static friction force, the workbench restarts again, and the sudden and sudden stops occur, thus working. The station will suddenly jump and stop, and continuously cycle, that is, the workbench and crawling phenomenon.
4 The main measures of the system structure into the hydraulic system 4.1 The design of the system structure 1) Appropriately increase the inner diameter of the large suction pipe to reduce or avoid the pipe bending 2) For the double joint vane pump, the correct piping method should be adopted 3) At the pump outlet A check valve should be installed at the place where the back pressure valve should be installed. 4) The exhaust plug should be installed at the highest point of the cylinder or pipe. 5) The hydraulic component design accuracy should meet the technical requirements. 6) The tank capacity should be appropriate to make the oil There is enough time in the tank to separate the bubbles.
4. 2 Equipment installation and maintenance aspects 1) Hydraulic pump should be as small as possible (500mm) 2) Hydraulic rotation should not be too high 3) Sealing of hydraulic components and pipe heads is good 4) Select appropriate oil filter And should always check, clean, avoid blocking 5) the fuel tank in the fuel tank to maintain a certain level of high level, or set a gap between the two 6) hydraulic control valve hole inlet and outlet pressure can not be too large (3.5 MPa 7) The fuel tank should ensure sufficient oil, the use right is not lower than the oil mark indicator line 8) The viscosity of the oil should not be too high, and should be replaced as required.
1 chapter Hongjia. Metal cutting machine hydraulic drive. Nanjing: Jiangsu Science and Technology Press, 1985 2 Shuguangguo. Hydraulic system fault diagnosis and troubleshooting. Beijing: Ocean Press, 1992 3 more swimming. Machine tool hydraulic and lubrication equipment maintenance manual. Beijing: Mechanical Industry Press, 1998
AGLEX Full Spectrum G 220W LED Grow Light applied with well-know brand, quality materials, ensuring they are with long lifespan and helping plants growing better and faster.
SUPERIOR CHIP TECHNOLOGY – Samsung LEDs are apllied to AGLEX G220 full spectrum LED Grow Light, more efficient and brighter than other LEDs. This results in our grow light being 20% more PAR and lumen than standard LED indoor grow light.
HIGHER YIELD - NEWEST Samsung LED technology and RELIABLE UL driver used, 2.8μmol/J, increase your yield 50% compared with other brand grow lights, 220W uniform PAR value at average 673umol at 18''height.
REFLECTOR AND FANLESS DESIGN - G220w led grow lamp is designed with reflector, contributing to high intensity light and excellent performance. All casing is heat sink and Fanless design will make your growing life easy and quiet. NO ANY NOISE. Suitable for indoor plants growing.
WIDELY USED - Our full spectrum sunlike led grow light is perfect to use for all stages of plant growth, from raising plants from clone to budding without swapping lights. Whether you're growing tomatoes, vegetable, strawberry, pepper, microgreen or herb, AGLEX grow light covers you all stage growing needs and helps you get high yields. Perfect for your own indoor live plant gardening, shelves and tent growing.
Full Spectrum LED Grow Light, LED Grow Light for Vertical Farming. aglex g220, led grow light 200w
Shenzhen Ameri Technology Co., Ltd. , https://www.aglexz.com