Bearing maintenance and lubrication.

TAG: roller beari ese ball bea | author:赛美瑞 | VISITORS: | source:未知

In order to make the bearing fully play and maintain its proper performance in the long run, it is necessary to make regular maintenance (regular inspection).It is important to improve productivity and economy through proper periodic inspection, early detection of faults, and prevention of accidents.Many bearings require regular maintenance to prevent premature failure.Although some, such as liquid bearings and magnetic bearings may need a small amount of maintenance, most of the bearings in high cycle operation need periodic lubrication and cleaning, and may need to adjust, in order to minimize the effects of wear and tear.


An unsealed bearing usually has a grease nipple, regularly lubricated with a grease gun, or a grease cup that is filled regularly.Before the 1970s, there were no sealed bearings, most of which were mechanical, and lubricating oil was a more common activity than today.For example, the use of "lubricating operations" almost always changes the engine oil, but today's chassis is mostly sealed.From the late 18th century through the middle of 1900, the industry relied on a number of workers who said they often lubricate machinery and oil tanks.

Today, factory machines usually have lubricating systems in which central pumps provide regular lubricating oil or grease, and so on.The timing and quantity of the lubricating oil cycle can be controlled by the computer, such as PLC or CNC, and manual operation.This process of automation is the lubrication of all modern CNC machines and many other modern factory machines.Similar lubricating oil system is used in the automatic machine, in this case, there was a hand pump, machine operators should pump used in the machine, once a day (or once a week).These are called disposable systems from their main selling point: a handlebar, a lubricant, rather than an ALEMITE gun pump or oil that can be placed in a dozen different locations around the machine.

The internal lubrication system of a modern automobile or truck engine is conceptually similar to the lubricating oil system, except for continuous pumping.This oil flow is directly connected to the bearing through the port through the drill hole or the engine cylinder block and the cylinder head casting into the channel, and other places provided oil bath.

Many bearings need to be lubricated and cleaned regularly in high-cycle industrial operations, and many require irregular adjustments, such as preload adjustment, to reduce the impact of wear and tear.Bearing life is greatly affected by clean and good lubrication.However, the limitations of many engineering applications make maintenance difficult.


How to clean the bearing?


When the bearing is removed for inspection, the appearance record should be done by photography and other methods.In addition, confirm the amount of the remaining lubricant and sample the lubricant and then clean the bearings.


A. The bearings are cleaned in coarse and fine wash, and can be placed on the bottom of the container.


B. Use a brush in oil to remove grease or adhesive during rough washing.If the bearing is rotated in oil, it will be noticed that the surface will be damaged by the foreign body.


C, in fine wash, slowly turn the bearing in oil, and it must be carried out carefully.The commonly used cleaning agent is neutral and non-aqueous diesel or kerosene, and sometimes it is also used with warm lye.No matter which cleaning agent is used, always keep the filter clean.After cleaning, immediately coating the bearing with anti-rust oil or anti-rust grease.


Bearing lubrication


Closed (ring) bearings are usually lubricated with grease.


It does not require special oil supply system, it has the advantages of simple sealing device, low maintenance cost and low grease cost. It is very common to use in bearings with low speed, medium speed and medium temperature.Especially in recent years, the advent of anti-wear additive and continuous development, improve the performance of grease lubrication, grease to get a wider range of application, the types and filling quantity of the grease and bearing structure is associated with specific industrial and mining, the bearing rotating speed generally the bearing under oil lubrication way;


Open bearings are usually lubricated by oil.


1) oil bath lubrication


Bearing is suitable for low and medium speed operation, the use of this method is to pay attention to the control of oil lubrication, oil level height should be slightly lower than the bottom of the center of the rolling element bearing too much oil will lead to excessive temperature rise of agitation, oil amount is insufficient and can cause premature failure of the bearing, recommended that oil level indicator (keep) the proper oil level


2) drip lubrication


Drip lubrication is the use of the self - weight of lubricating oil, drop by drop to the friction pair.Oil injection cup with oil needle valve in its oil supply position.This kind of lubrication method is used in a small number of friction pairs, such as machine guide, bearing, gear, chain and so on.When the bearing parts need to be supplied with the lubricating oil, the oil can be lubricated by dripping oil, which is generally suitable for every 3 ~ 8 seconds, because excessive amount of oil will increase the temperature of the bearing.


3) circulating oil lubrication.


When the bearing is running at a high speed, the bearing temperature rise will increase accordingly, resulting in the aging of oil.Circulating oil lubrication can effectively prevent the above phenomena.The lubricating oil is sent to the bearing part through the oil pump, and at one end of the bearing, an inlet is installed, and an oil outlet is installed at the other end of the bearing.After the bearings are filtered and cooled, the oil can be recycled.Because the lubricant can take away certain heat in the circulation process, it can guarantee that the bearing is always maintained at lower temperature, so this method is suitable for bearing parts with higher rotating speed.But note that the oil inlet should be larger than the inlet, so that no remaining oil is left in the bearing seat.


4) spray lubrication


When the bearing is in low - medium load at high speed, the rolling body and the cage also rotate at a fairly high speed to make the air swirl around the bearing.In order to ensure the enough quantity of lube oil supply high speed bearing, must from one end bearing will be using the method of high-pressure jet spray lubricating oil to the bearings and the bearing lubrication, the lubrication oil then from the other end to flow into the tank.Using this method and for effective lubrication bearing, we should pay attention to keep the position of the high pressure spray nozzle is located in the inner ring and between the center and lubricating oil injection speed should be not less than 15 m/s and oil directly into the bearing.


5) oil and gas lubrication


When the bearing is under high speed, high temperature and heavy load, the oil mist is mixed with compressed air and a small amount of lubricating oil to spray into the bearing of each operation.Compared with other lubrication methods, this method has the lowest operating temperature, so it is allowed to have the highest speed.High pressure airflow can be used to cool the bearings and effectively prevent impurities from intruding.


6) solid lubrication


If you use oil lubrication and grease lubrication can not meet the required by the bearing lubrication conditions, or failing to meet specific working conditions, you can use solid lubricant, or try to improve the lubrication performance of bearing itself.In meet the use conditions, adding a small amount of solid lubricant grease, such as adding 1 of 3-5% molybdenum disulphide can reduce wear and improve the compressive strength heat-resistant ability, for high temperature and high pressure, high vacuum, corrosion resistance, resistance to radiation, and the special conditions such as extremely low temperatures, the solid lubricant in engineering plastics and