2015年1月29日星期四

The adjustment of high speed bearing

If the calculation results of contradiction is too large (usually have this situation only at the highest speed), only take double lubricating measures under ring lubrication method and static pressure lubrication method,which is likely to make the DMN value exceeded 3 million of the bearing.

  Considering the high speed bearing clearance  not only include the factors mentioned above, but also  the effect of thermal elongation axis on the clearance of the bearing. The requirements in the working state, which has the best clearance at operating temperature.

  This clearance formed under the condition of the inner ring and the outer ring of the  ball groove center aligned accurately. As thehigh precision bearings to reduce the relative sliding and internal friction, clearance of SKF 71900C/DB angular contact ball bearing had better not use relative displacement methods within the inner ring and the outer ring along the axial direction to adjust the ball bearing.


2015年1月26日星期一

The coordination of high-speed bearing


high-speed bearings with clearance due to the requirements of the high speed for both high precision bearings  and  high temperature bearing, so in consideration of its coordination and clearance, to take into account the following two points:

(1) changes in the size and hardness changes when the temperature rose from     ambient temperature;
(2) force line change and shape change under high-speed centrifugal force caused by.

In short, in the high precision ball bearings and high temperature conditions, and with clearance from the selection of want to keep a bearing on the accuracy and performance, this is difficult.

In order to ensure the bearing after installation of the rolling deformation is small, the amount of interference can not KOYO 7319AC angular contact ball bearing interference fit get too large, and high speed centrifugal force and high temperature thermal expansion, or set off with the normal surface pressure.

Or relax the mating surface , so the amount of interference must considering the above two kind of factors under the carefully calculated, the effective amount of interference may be invalid for the high-speed bearing in the normal speed.


2015年1月23日星期五

high speed bearing

High speed, medium speed and low speed bearing, not on speed set but in line speed set. Smallbearings motionless tens of thousands turn not high-speed bearing, large bearing hundreds ofturning even high-speed bearing.
  High speed bearings generally refers to the bearing speed reached 60 meters per second. In the sliding bearing, hydrostatic bearings, hydrodynamic bearings, aerostatic bearings, hydrodynamic gas bearings are suitable for high speed rotation.
  But the general rolling bearing adapted to low speed rotation, if the use of rolling bearings of high speed rotating need special requirements. The above bearings are in Chinese standard, it is easy to search to the bearing, reasonably choose the model according to the use of the load and other factors.
  If the speed between 5 to 60 meters per second, if not on the high-speed bearing, as long as the general bearing lubrication basic can satisfy. If the bearing use higher speed in some special occasions, such as high speed rotary bearing used in high speed cutting machine or precision machining machine tool can also be used for bearings, magnetic bearings, ceramic bearingselectric power special, but contact with the professional manufacturers.

2015年1月14日星期三

What are the reasons for the simple view of thin-walled deep groove ball bearing overheating

Thin-walled deep groove ball bearings for many people now in general has a corresponding industrialization information circumvention methods, for the target of many reasons the corresponding industries, these should be the significance and the method has more measures, as far as possible in order to accomplish this information, thin-walled deep groove ball bearings in any situation display it is difficult to understand.
The thin wall in a certain extent, deep groove ball bearing is also a lot of assigned under the principle of preparation methods, since it can correspond to terms can appear on the principle of understanding and summary from each aspect, in any case can not strengthen summarize some qualitative real strength. Thin-walled deep groove ball bearings if the four point contact ball slewing bearing overheating, there may be several reasons: 1, the oil is too thick. 2, oil is too thin, high-quality mineral oil should be chosen by the changes of temperature effect is small and not easily foaming. 3, the oil containing impurities and sand. 4, the belt too tight, 5, a belt wheel hub and bearing friction. 6, motor installation is improper, will make the armature shaft shoulder pull or push a bearing. Thin-walled deep groove ball bearings if near the cross roller bearings installation with a relatively large source, or thin wall deep groove ball bearings to deal with the impact load, recommend the use of spherical roller bearings or thrust spherical roller bearings. Standard thin-walled deep groove ball bearing is not suitable in bad (load, rotational speed, the operating temperature, the amount of lubricant, vibration environment) under the working conditions.
So these are in certain circumstances inevitably gets thin section angular contact bearings accurate information more atmosphere and industrial development, these are also can think and more understanding of the principles of thin-walled deep groove ball bearing significance.