As a kind of sub-class of bearings, deep groove ball bearings are widely used in modern equipment manufacturing industry because of their wide application and long service life. The processing precision and quality of equipments have been greatly improved. It can be said that deep groove ball bearings In the future equipment installation will be a large number of applications, and its market prospects will be broader.
The wide application of deep groove ball bearings has benefited from the common understanding of the majority of equipment workers, and has been accepted by everyone for its excellent performance. I have been engaged in the maintenance and repair of mechanical equipment for many years. I have contacted deep groove ball bearings in many aspects, and I have a lot of understanding about its installation, use and maintenance. I have summarized some experiences and discussed with you.
(1) Characteristics of deep groove ball bearings
The deep groove ball bearing has a simple structure and is easy to achieve high manufacturing precision compared with other types, so it is easy to be mass-produced in series, and the manufacturing cost is also low, and the use is extremely common. The axial load carrying capacity is increased when a larger radial clearance is selected, and the contact angle is zero when subjected to a pure radial force. When there is an axial force, the contact angle is greater than zero. Generally, a stamped wave cage is used, a solid cage is used, and a nylon frame is sometimes used. In addition to the basic type, deep groove ball bearings also have various modified structures, such as: deep groove ball bearings with dust cover; deep groove ball bearings with rubber seals; deep groove ball bearings with snap grooves; Deep groove ball bearings with large load capacity of the ball notch; double row deep groove ball bearings. But they all have the following common features:
1. Each ferrule of the structure deep groove ball bearing has a continuous groove type raceway whose cross section is approximately one third of the circumference of the ball. It is mainly used to bear radial load and can also bear a certain axis. Direction load
2. When the radial clearance of the bearing increases, it has the property of angular contact ball bearing and can bear the axial load alternating in two directions;
3, the friction is small, the rotation speed is high;
4, the structure is simple, the manufacturing cost is low, and it is easy to achieve high manufacturing precision;
5, generally use stamping wave cage, the inner diameter is greater than 200mm or high-speed running bearings, using the car body cage.
(2) Installation and application maintenance
Deep groove ball bearings are the most representative rolling bearings and are widely used. Suitable for high speed or even high speed operation, it is very durable, low maintenance and long operating cycle. However, professional technicians are required to regularly check and maintain to ensure the safety, reliability, and operation cycle and quality of the operation.
Assembly of a deep groove ball bearing
The assembly of deep groove ball bearings requires assembly personnel to have high expertise and strictly enforce technical requirements and operating procedures during the assembly process.
Whether the bearing is installed or not will affect the accuracy, life and performance of the bearing. Therefore, please fully study the installation of the bearing, and install the bearing in accordance with the following operating standards.
1. Clean the bearings and related parts (for oil-lubricated bearings and double-sided oil seals or dust caps, seal bearings need not be cleaned before installation).
2. Check the size and finishing of the relevant parts.
3. Installation method The installation of the bearing should be based on the bearing structure, size and the matching nature of the bearing components. The pressure should be directly applied to the end face of the ferrule, and the pressure should not be transmitted through the rolling elements.
(3) The bearing installation generally adopts the following method
Press-fit: the inner ring of the bearing is tightly fitted with the shaft. When the outer ring and the bearing housing hole are loosely fitted, the bearing can be pressed onto the shaft by a press, and then the shaft is fitted into the bearing housing hole together with the bearing. When pressing, the bearing sleeve (copper or mild steel) made of soft metal material is placed on the end surface of the inner ring of the bearing. The outer ring of the bearing is tightly matched with the hole of the bearing seat. When the inner ring and the shaft are loosely matched, the bearing can be used. First press into the housing bore, then the outer diameter of the mounting sleeve should be slightly smaller than the diameter of the housing bore. If the bearing ring and the shaft and the seat hole are tightly fitted, the inner ring and the outer ring should be pressed into the shaft and the seat hole at the same time, and the structure of the assembly sleeve should be able to simultaneously tighten the end faces of the inner ring and the outer ring of the bearing.
Heating and fitting: It is a common and labor-saving installation method by heating the bearing or the bearing seat and using the thermal expansion to transform the tight fit into a loose fit. This method is suitable for the installation of bearings with large interference, before hot loading. Put the bearing or the ferrule of the separable bearing into the fuel tank and heat it evenly at 80-100 °C, then remove it from the oil and load it on the shaft as soon as possible. To prevent the inner ring end face and the shoulder from sticking tightly after cooling, the bearing is cooled. Axial fastening can be performed again. When the outer ring of the bearing is tightly fitted with the bearing seat made of light metal, the hot-filling method of the heated bearing seat can avoid the abrasion of the mating surface. When heating the bearing with the fuel tank, there should be a grid at a certain distance from the bottom of the box, or the bearing should be hung with a hook. The bearing should not be placed on the bottom of the box to prevent the sinking of impurities into the bearing or uneven heating. There must be a thermometer in the tank. Strictly control the oil temperature should not exceed 100 °C to prevent tempering effect and reduce the hardness of the ferrule.
The mounting method of the bearing is generally the case where the shaft rotates. Therefore, the cooperation between the inner ring and the shaft is a win-win cooperation, and the cooperation between the outer ring of the bearing and the bearing chamber is a clearance fit. Bearing operation check After the installation of the bearing is completed, the operation check should be performed immediately, and it is determined whether the installation is normal.
Operation and maintenance
Reliable maintenance work is the main means to ensure long-term operation of the bearing. When the equipment is running for a period of time, professional and technical personnel should be inspected and maintained in time, mainly in the following aspects:
1. Check the running temperature of the bearing, which is required to be below 65 degrees.
2. Check the axial movement of the moving parts, mainly whether the clearance of the bearing meets the requirements.
3. Check the inside and outside of the bearing for defects such as pitting, corrosion, pits and cracks.
4, the lubrication of lubricating oil or grease, should be replaced or added in time, but not too much, requiring one-third to one-half of the lubricating oil, one-third of the grease.
Case Analysis
The urea deep hydrolysis device is the terminal device for wastewater treatment in the fertilizer industry. Its core equipment hydrolysis pump is multi-stage, high-speed, high-temperature, high-pressure equipment. The operation is unstable for many years, which greatly affects the production of urea.
Mainly manifested in the short cycle of the bearing, the machine vibration and other faults. After everyone's analysis, the bearing type is not suitable. After carefully summarizing the characteristics of the hydrolysis pump, it is decided to use deep groove ball bearings. After confirming, we have established the installation and maintenance procedures for the bearing. Strictly implemented. After the transformation, the operating condition is good and the operating cycle has increased greatly, which strongly supports the stable production and high yield of our company's urea products.
summary
At present, China's demand for bearings is relatively optimistic, such as cars, cars, motorcycles, clicks, household appliances and automated office machinery and other host industries, the South-to-North Water Transfer, the West-East Gas Pipeline and the Shanghai World Expo, which is currently ending, have confirmed China's complete set of construction equipment. And engineering equipment has a larger demand.