Worm gear and worm reducer

                                                  Worm gear and worm reducer

The worm gear reducer is a power transmission mechanism, which uses the speed converter of the gear to decelerate the rotation of the motor (motor) to the desired rotation,
brief introduction
It can be seen in the transmission system of various machinery, from ships, automobiles, locomotives, heavy machinery and tools for construction, processing machinery and automatic production equipment used in the machinery industry, to common household appliances, clocks and watches in daily life. The application of the reducer can be seen from the transmission of large power to the transmission of small load and accurate angle. In industrial applications, the reducer has the functions of reducing speed and increasing torque. Therefore, it is widely used in speed and torque conversion equipment.
The main functions of the reducer are: worm gear reducer worm gear reducer 1. Reduce the speed and increase the output torque at the same time. The torque output ratio shall be multiplied by the motor output by the reduction ratio, but it shall not exceed the rated torque of the reducer.
2. Deceleration also reduces the inertia of the load, which is the square of the reduction ratio. You can see that general motors have an inertia value. [1]
And get the mechanism with larger torque. In the current mechanisms used to transmit power and motion, the reducer is widely used.
structure
Structure diagram of worm gear reducer structure diagram of worm gear reducer basic structure of RV series aluminum alloy worm gear reducer is mainly composed of transmission parts worm gear, shaft, bearing, box and its accessories. It can be divided into three basic structural parts: box, worm gear, bearing and shaft combination. The box is the base of all accessories in the worm gear reducer. It is an important accessory to support and fix the shafting components, ensure the correct relative position of the transmission accessories and support the load acting on the reducer. The worm gear is mainly used to transmit the motion and power between the two staggered shafts, and the bearing and shaft are mainly used to transmit power, operate and improve efficiency.
Some accessories of worm gear reducer are explained as follows:
Shell: aluminum alloy (base: 025-090) cast iron (base: 110-150);
Worm: 20Cr steel. Carbonitriding and nitrocarburizing treatment (maintain the tooth surface hardness HRC60 after fine grinding, and the hardness thickness is greater than 0.5mm);
Worm gear: specially equipped with wear-resistant nickel bronze;
The oil cover / breather is mainly used to exhaust the gas in the case of the worm gear reducer;
The end cap is divided into large end cap and small end cap. The end cap is used to fix the axial position of the shafting components and bear the axial load. Both ends of the bearing seat hole are closed with bearing caps;
Oil seal; It is mainly used to prevent the leakage of lubricating oil inside the chassis and improve the service time of lubricating oil;
The oil drain plug is mainly used to drain the dirty oil and clean the oil when replacing the lubricating oil;
The oil level indicator cover / oil level indicator is mainly used to observe whether the oil level inside the case of the worm gear reducer meets the standard;
classification
Main models: WP series worm gear reducer, wh series worm gear reducer and CW series worm gear reducer, etc.
WP series
Including wpa/wps/wpw/wpe/wpz/wpd.
Wh series
Including wht/whx/whs/whc.
Folding CW series
Including cwu/cws/cwo.
Fold RV series
Including rv/nmrv/nrv.
summary
RV series worm gear reducer is designed and manufactured according to technical quality standards. RV series worm gear reducer is based on the national standard gb10085-88 cylindrical worm gear parameters, absorbs advanced science and technology at home and abroad, has a novel "square box" shape structure, and the box shape is beautiful. It is made of high-quality aluminum alloy die-casting. RV series worm gear reducer has been widely used in mechanical reduction devices of production process equipment in various industries. It is the best choice for modern industrial equipment to realize high torque, high speed ratio, low noise and high stability mechanical reduction transmission control device.
characteristic
1. Compact mechanical structure, light volume and shape, small and efficient;
2. Good heat exchange performance and fast heat dissipation;
3. Simple installation, flexible and light, superior performance and easy maintenance;
4. Stable operation, low noise and durability;
5. Strong usability, high safety and reliability;
model
RV25
RV30
RV40
RV50
RV63
RV75
RV90
RV110
RV130
RV150
NMRV30
NMRV30
NMRV40
NMRV50
NMRV63
NMRV75
NMRV90
NMRV110
NMRV130
NMRV150
NRV25
NRV30
NRV40
NRV50
NRV63
NRV75
NRV90
NRV110
NRV130
NRV150
Use and maintenance
1. During installation, please do not apply pressure on the output parts and box body of the reducer. During connection, please meet the corresponding requirements for coaxiality and verticality between the machine and the reducer.
2. The lubricating oil shall be changed again after the initial operation of the reducer reaches 400 hours, and the subsequent oil change cycle is about 4000 hours.
3. Sufficient lubricating oil shall be reserved in the reducer box and regularly checked.
4. Pay attention to keep the appearance of the reducer clean, and timely remove dust and dirt to facilitate heat dissipation.
Fold and edit this national standard
TP type planar enveloping toroidal worm gear reducer (jb/t9051-1999)
CW series circular arc cylindrical worm reducer (jb/t7935-1999)
ZC1 double stage worm and gear worm reducer (jb/t7008-1993)
SCW shaft mounted circular arc cylindrical worm gear reducer (jb/t6387-1992)
CW series circular arc cylindrical worm reducer (gb9147-88)
Wh series circular arc cylindrical worm reducer (jb2318-79)
Plane enveloping hourglass worm reducer (zbj19021-89)
PW type planar double enveloping hourglass worm gear reducer (gb/t16446-1996)
Circular arc cylindrical worm reducer (gb9147-88)
Cause analysis of common problems of worm gear reducer: gear worm gear reducer is a kind of transmission machinery with compact structure, large transmission ratio and self-locking function under certain conditions. Moreover, it is easy to install and reasonable in structure, and has been more and more widely used. A helical gear reducer is installed at the input end of the worm gear reducer. The multi-stage reducer can obtain very low output speed, has higher efficiency than the single-stage worm gear reducer, and has low vibration, noise and energy.
common problem
Common problems and their causes.
(1) Heating and oil leakage of reducer,
(2) Worm gear worn,
(3) The transmission pinion is worn,
(4) The bearing (worm) is damaged.
Heating and oil leakage
In order to improve efficiency, worm gear reducers generally use non-ferrous metal as worm gear and hard steel as worm. As it is a sliding friction drive, it will generate high heat during operation, which will cause differences in thermal expansion between reducer parts and seals, resulting in gaps on all mating surfaces. As the temperature rises, the oil becomes thinner, which is easy to cause leakage. There are four main reasons: first, whether the material matching is reasonable; second, the surface quality of the meshing friction surface; third, the selection of lubricating oil and whether the addition amount is correct; fourth, the assembly quality and the use environment.
Worm gear wear
The worm gear is generally made of tin bronze. The matched worm material is generally hardened to hrc45-55 with 45 steel, and also commonly hardened to hrc50-55 with 40c: and ground to the roughness Rao by worm grinder 8 FCM. During normal operation of the reducer, the worm is like a hardened "file", which keeps filing the worm gear, causing wear to the worm gear. Generally speaking, this kind of wear and tear is very slow. For example, some reducers in a factory can be used for more than 10 years. If the wear speed is fast, it is necessary to consider whether the type selection of reducer is correct, whether there is overload operation, the material of worm gear, assembly quality or service environment.
Helical gear wear
It usually occurs on the reducer installed vertically, which is mainly related to the amount of lubricating oil added and the selection of lubricating oil. During vertical installation, it is easy to cause insufficient lubricating oil. When the reducer stops running, the transmission gear oil between the motor and the reducer will be lost, and the gear will not get the proper lubrication protection. The lack of effective lubrication during startup or operation will lead to mechanical wear and even damage.
Folding bearing damaged
When the reducer breaks down, even if the reducer is well sealed, the factory often finds that the gear oil in the reducer has been emulsified and the bearing has been rusted, corroded and damaged. This is because the gear oil is caused by the condensation of water generated after the reducer is heated and cooled during the operation and shutdown of the reducer; Of course, it is also closely related to bearing quality and assembly process
resolvent
1. ensure assembly quality. Some special tools can be purchased or self-made. When disassembling and installing reducer components, try to avoid knocking with hammers and other tools; When replacing gears and worm gears, try to use original accessories and replace them in pairs; When assembling the output shaft, pay attention to the tolerance fit; The hollow shaft shall be protected with anti sticking agent or red lead oil to prevent wear, rust or scale on the mating area, which is difficult to disassemble during maintenance.
2. selection of lubricating oil and additives. Generally, the gear oil 220# is selected for the worm gear reducer. For the reducer with heavy load, frequent startup and poor service environment, some lubricating oil additives can be selected to make the gear oil still adhere to the gear surface when the reducer stops running and form a protective film to prevent the direct contact between heavy load, low speed, high torque and metal during startup. The additive contains sealing ring regulator and anti leakage agent to keep the sealing ring soft and elastic and effectively reduce lubricating oil leakage.
3. selection of installation position of reducer. Vertical installation shall not be adopted if the location permits. In vertical installation, the amount of lubricating oil added is much more than that in horizontal installation, which is easy to cause heating and oil leakage of the reducer.
4. establish lubrication maintenance system. The reducer can be maintained according to the "five determinations" principle of lubrication work. Each reducer shall be regularly inspected by the responsible person. If the temperature rise is obvious, exceeding 40 ℃ or the oil temperature exceeds 80 ℃, the quality of the oil is reduced, or more copper powder is found in the oil and abnormal noise is generated, the reducer shall be stopped immediately, repaired in time, the fault shall be eliminated and the lubricating oil shall be replaced. When refuelling, pay attention to the oil quantity to ensure that the reducer is properly lubricated.
Maintenance method
In view of the wear problem, the traditional solution of enterprises is repair welding or machining repair after brush plating, but both of them have certain disadvantages: the thermal stress generated by repair welding at high temperature cannot be completely eliminated, which is easy to cause material damage and lead to bending or fracture of components; However, due to the limitation of coating thickness, brush plating is easy to peel off, and the above two methods use metal to repair metal, which cannot change the "hard to hard" coordination relationship, and will still cause re wear under the comprehensive action of various forces. For some large bearing enterprises, they are often unable to solve the problem on site and have to rely on outsourcing repair. Modern western countries mostly adopt the repair method of polymer composite materials to solve the above problems, and the most widely used are meijiahua technology products, which have super adhesion, excellent compressive strength and other comprehensive properties. The application of polymer materials for repair can avoid disassembly and machining. There is no effect of repair welding thermal stress, and the repair thickness is not limited. At the same time, the metal materials of the product do not have the concession, which can absorb the impact vibration of the equipment, avoid the possibility of re wear, and greatly extend the service life of equipment components, saving a lot of downtime for the enterprise and creating huge economic value. For the leakage problem, the traditional method needs to disassemble and open the reducer, replace the sealing gasket or apply sealant, which is not only time-consuming and laborious, but also difficult to ensure the sealing effect, and leakage will occur again in operation. The polymer material can control the leakage on site. With its superior adhesion, oil resistance and 350% elongation, the material overcomes the impact caused by the vibration of the reducer and solves the problem of reducer leakage for enterprises