First, the characteristics and functions of closed gear transmission lubrication 1 gear lubrication characteristics (1) Compared with the sliding bearing, most gears have a small radius of curvature of the tooth profile, generally tens of mils, so the conditions for the formation of the oil wedge are poor.
(2) The tread contact stress of the gear is very high, and the contact stress of the tooth surface of some heavy-duty machinery such as cement mill, crane, winch and rolling mill reducer can reach 4001000MPa.
(3) There are both rolling and sliding between the tooth surfaces, and the direction and speed of the sliding change sharply.
(4) Lubrication is intermittent, and the oil film needs to be re-formed every time the meshing is formed, and the conditions for forming the oil film are poor.
2 Lubrication of gear transmission The lubrication method of closed gear transmission is immersion lubrication and injection lubrication. Generally, it is determined according to the circumferential speed of the gear.
Selection of industrial gear lubricant type Conditioning tooth surface contact stress (N/mm) Gear condition Use industrial gear oil recommended for use under low load Medium load heavy load <3503505005007507501100>1100a tempering treatment, the meshing accuracy is equal to 8 b The ratio of the number of teeth to i<8c is the ratio of the maximum sliding speed to the circumferential speed of the indexing circle vg/v<03d, the displacement coefficient x1=x2, the displacement coefficient x1< or >x2a, and the precision of the meshing is equal to or higher than the level b. Vg/v>03 carburizing and quenching, surface quenching and heat treatment hardness 58-62HRC general gear transmission impact gear transmission mine hoist, open-pit mining machine, cement mill, chemical machinery, water conservancy and electric machinery, metallurgy and mineral machinery, ship port machinery Gear transmission metallurgical rolling, downhole mining, high temperature impact, gear transmission in watery parts, etc. (1) Oil immersion lubrication: When the circumferential speed of the gear is V<12m/s, the large gear is usually immersed in the oil pool for lubrication and immersion. The depth of the oil is at least 10mm. When the rotation speed is low, it can be deeper, but if it is too deep, it will increase the resistance of the movement and increase the oil temperature. In the multi-stage gear transmission, the gear is not immersed in the oil pool.
(2) Injection lubrication: When the circumferential speed of the gear is V>12m/s, the gear is stirred vigorously due to the large peripheral speed, and the oil adhering to the tooth profile has been smashed, and it is not easy to use oil immersion lubrication. Injection lubrication should be used, that is, an oil pump is used to spray a certain pressure of lubricating oil through the nozzle onto the meshing tooth surface.
3 The role of gear lubricant (1) to reduce the wear of gears and adjacent moving parts.
(2) Reduce friction and work.
(3) Heat dissipation, acting as a coolant.
(4) Reduce noise, vibration and impact between gear teeth.
(5) Eliminate dirt.
The hydraulic system condition monitoring technology is a technical state that understands and masters the internal parts of the hydraulic system during the operation of the system, and measures certain characteristic parameters (such as pressure, flow, temperature, speed, sealing performance, etc.) of each original. Obtain information from vibration and noise, and process it through integrated circuit, microcomputer technology (digital display technology) and electronic control technology to obtain scientific conclusions, and then compare the measured value with the normal value of the dynamic pressure parameter of the original hydraulic system. A comprehensive technique for judging whether the performance of each original is normal and then accurately estimating the remaining life of the original. This process is done by a modern hydraulic system monitor (tester). Condition monitoring is the primary diagnosis of hydraulic components, which is more random. Condition monitoring is the basis and the acquired signals should be accurate.
Fault diagnosis is the judgment of the cause, location and severity of the failure of the hydraulic original, and it is a precise diagnosis of the health of the original parts of the hydraulic system. The goal of precision diagnosis is to conduct an expert consultation on the primary diagnosis results, that is, to test, analyze and accurately judge the hydraulic components.
Fault diagnosis is based on condition monitoring. There are many ways to diagnose hydraulic system faults, and they are still moving forward. Up to now, based on the characteristics of extracting mechanical physical signals, the application of integrated optical and electronic-electrical-integration technology based on integrated digital signals to obtain digital-analog display signals has been applied to hydraulic system fault detection equipment, accelerating hydraulic system fault diagnosis technology. development of. At present, domestic and foreign hydraulic system detectors, such as YSZ-B hydraulic system detector produced by Suzhou Hydraulic Accessories General Factory, YC-C hydraulic system monitor produced by Beijing General Staff Headquarters Engineering Bureau, CDK799 produced by Chengdu Komatsu Institute of Technology -101A digital hydraulic system tester, etc., all adopt advanced large-scale integrated circuits, electronic technology, computer technology and signal processing technology as detection carriers, and widely adopt the real-time fault diagnosis system and electronic control system. In the process of hydraulic system fault diagnosis, an automated diagnostic system based on auxiliary diagnosis is established to realize signal acquisition, feature extraction and state recognition automation, and the nature, degree, category, location, cause and trend of faults are automatically completed by microcomputer technology. Diagnostics help engineers and technicians make quick decisions, but they can't solve the drawbacks of disintegration testing.
The non-disintegration detection of hydraulic system is the best way and effective way to solve the above problems. The hydraulic system does not disintegrate detection by using modern advanced science and technology, electronic technology, computer technology and ultrasonic technology. The time difference flow signal and pressure signal generated by the integrated carrier signal of flow velocity, pressure and sound when the liquid flows through the pipeline are the receiving bodies. Integrate various sensors to perform on-line real-time detection of hydraulic system dynamic pressure parameters (pressure, flow, temperature, speed, and sealing performance).
The hydraulic system is not disintegrated and has been recognized. At present, no matter in agriculture, industry and other industries are pursuing production efficiency, economic benefits and development speed, hydraulic system non-disintegration detection is the development direction of future hydraulic system failure detection, which can not only improve the detection speed of hydraulic system, but also save energy. It has good expected results in reducing environmental pollution and reducing labor intensity. The hydraulic system non-disintegration detection technology will play its important role in the field of hydraulic system condition monitoring and fault diagnosis.
(6) The role of structural materials. Lubricants improve resistance to gluing and are a factor in preventing gear breakage, pitting, and gluing.
Second, the characteristics of the open gear transmission lubrication and the requirements of its lubricant performance, the transmission speed is low, usually with manual regular lubrication, and open gear transmission is easy to fall into dust, debris and other external media and cause lubricant pollution The gear is prone to abrasive wear. When the split gear is covered with dust, the lubrication requirements of the open gear are the same as those of the closed gear under the same working conditions. Open gear drives typically use high viscosity oils, asphaltene lubricants or greases and work more efficiently at lower speeds. There are currently three grades of open gear oil classification, namely ordinary open gear oil (CKH), extreme pressure open gear oil (CKJ) and solvent diluted open gear oil (CKM).
When selecting open gear transmission lubricants, the following factors should be considered: degree of closure; circumferential speed; gear diameter size; environment; use of lubricating oil; accessibility of gears.
An oil sump should be provided except that in some cases the lubricant can be circulated back. The lubrication method of open gear transmission is generally full loss type, and any full loss type lubrication system will only have a thin layer of cover film on the surface of the gear. They are often under boundary lubrication conditions because of the new oil added to the tooth surface. Or grease, which is squeezed out due to the pressure of the tooth surface, combined with the centrifugal force during the rotation of the gear, can only leave a thin oil film on the tooth surface, and then consider the grinding cooperation of the gear, so the lubricating oil must have High viscosity or high consistency and strong adhesion to ensure a continuous film of oil remains on the gear surface.
Bicycle Toptube Bag
Jiaxing Love Riding Electronic Technology Co.Ltd. , https://www.loveriding.cn