Precautions for grease using on spherical roller bearings

Spherical roller bearings in the process of using lubrication is an important part, so many people think that the more grease the bearings as possible
In fact, grease filling volume can refer to the following principles: (a) general bearing grease should be filled in order to install the bearing cavity 1/2-3/4 entire space can; (2) the level of the bearing cavity filled Space 2/3-3/4; (3) vertically mounted bearing space filled cavity 1/2 (upper side), 3/4 (the lower side); (4) is easily polluted environment, the speed or medium-speed bearings, bearings and bearing boxes should fill the entire space; (5) should be preceded by high speed bearing grease in the bearings mounted on the quality lubricants, in general, is loaded with grease base oil immersion what to avoid during startup due to friction caused by inadequate bearing surface grease burn.

Spherical roller bearing grease is usually apparent viscosity or viscosity similar to that in the description of the viscosity of the grease, you must specify the temperature and shear rate. Similar indicators can be used to control the viscosity of low temperature fluidity and pumpability. Measure of self-aligning roller bearing grease temperature performance is one of the important indicators of low torque, ie at low temperatures (-20 ° c less) rotation of the bearing grease blocking low degree of liquidity, low torque grease from the start 60mm rear torque and rotational torque mean value. Spherical roller bearing grease evaporation (degrees) that grease in the long-term use under high temperature conditions, the extent of volatile oil grease, the smaller the better evaporation. Grease lubricant evaporation depends on the nature and composition of fractions. Oxidation stability is in long-term storage or long-term grease when used under high heat resistance and oxygen role in maintaining a permanent change in the nature of capacity does not occur. Due to oxidation, reduction or tend to occur free alkali content of free organic acid content increases, the drop point decline, the appearance of darker, appear different odor, consistency, strength limit, similar to the viscosity decreases, and destruction of corrosion products generated grease structure substances, resulting soap oil separation. Therefore, in the long-term storage grease, should be stored in dry and ventilated environment, prevent sun exposure, and should be regularly checked the free base or free acid, corrosive and other changes in the project in order to ensure its quality and performance.

First, use the installation should carefully allow a strong punch, motor bearings adverse phenomena solutions allow a direct hit with a hammer bearing, not pass through the rolling pressure.

Second, the use of appropriate and accurate installation tools make use of special tools, try to avoid using fabric and staple fibers and the like.

Third, try to keep their surroundings clean bearing motor bearings generally use sodium based grease smile even invisible dust from entering the spherical roller bearings, will increase bearing wear, vibration and noise.

Fourth, to prevent corrosion of bearings : Direct hands to take bearings, to fully wash hands sweat, and coated with high-quality mineral oil before, during the rainy season and summer with particular attention to rust. In some special operating conditions, the bearings can get a longer life of the conventional calculation, especially in the case of light load. Bearing housing labyrinth seal mechanism and influencing factors of these special operating conditions is, when the rolling surface (track and rolling elements) is an effective lubricant film separating and limiting pollutants may lead to surface damage.

Timken Bearings-Small bearing loading Giant mechanical

Timken bearings numerous heavyweight equipment, innovative technologies and products for many customers to solve difficult problems. Because reputation, whenever they have a new customer or pressing challenges, the Timken Company (TIMKEN) became their best recourse.

When a monster weighing 12,430 tons transported when needed, Timken bearings without unexpectedly become the preferred supplier. This weight is equivalent to 1.5 Eiffel Tower or the Statue of Liberty 55 supercomputer is a set of oil production equipment, by the British ALE transport company responsible for transport, is the history of a handful of times one of the top-scale land transport. For ALE companies, but also a great challenge. As bulky, weight amazing, ALE modular decentralized transportation company intends to require Germany Scheuerle FahrzeugfabrikGmbH company produces 224 modular transporter to carry the equipment. So the weight of wheel bearings for transportation purposes nature is a severe test, once the wheel bearing strength is not enough, it is easy to crack. Therefore, Scheuerle company chose Timken Company (TIMKEN) to be responsible for providing all of the wheel bearings, because Timken tapered roller bearings reload capability can guarantee this monster reach the destination safely and smoothly.

Despite a wealth of experience and leadership to carry heavy friction management technology, Timken Company (TIMKEN) for the challenge this time is not taken lightly. The production of wheel bearings used in Timken's steel products have been a special reinforcement, than the general solidity Timken bearings also. The very smooth trip transportation, supercomputer scheduled arrival at the destination England Hartlepool. Small Timken bearings through its excellent capacity, once again played an extraordinary impetus

Self-aligning ball bearings’ profile

Self-aligning ball bearings changed the way of bearing friction, rolling friction, this method is more effective to reduce the friction between the bearing surface phenomenon, effectively increasing the fan bearing life, and therefore the use of the heat sink life expectancy. The disadvantage is that technology brings more complex, which will raise costs, but it also brings higher operating noise.

NTN tapered roller bearing size program and a series

1.Size program dimensionplan including NTN tapered roller bearings dimensions of the system or tables.

  2 Bearings bearingseries a specific type of rolling bearing, with gradually increasing size, in most cases have the same dimensions, and the contact angle between a certain relationship.

  3 Dimensions series dimensionseries width or height series series series combination with a diameter of tapered roller bearings also include angle.

  4 diameter series diameterseries our current standard size part of the program, bearing outside diameter increment series, for each standard bearing diameter, it has a diameter series, and two diameters often have a specific relationship between.

  5 width series widthseries our current standard-size part of the program. Bearing width increment series, for each series bearing bore diameter, has a width series.

  6 height series heightseries size of the current standard thrust bearing part of the program. Bearing height increment series, for each series bearing bore diameter, with a height series.

  7 Angle Series angleseries our current standard NTN tapered roller bearing size part of the program. A specific range of contact angle.

Material requirement for SKF Spherical roller bearing

SKF Spherical roller bearing rings and rolling elements, to withstand repeated high contact pressure and at the same time accompanied by a sliding rolling contact. Retainer it? Side with the rings and rolling elements on both sides, or one side sliding contact side under tension and compression forces. Because of the above reasons, the bearing rings, rolling the material of the performance has the following basic requirements: 1, 2 rolling fatigue strength, high hardness, 3, 4 high wear resistance, dimensional stability, good 5, mechanical strength bearing performance requirements of the cage: 1, 2 high abrasion resistance, dimensional stability 3, the mechanical strength

Turning shaft workpiece accuracy analysis

Shaft parts in the turning process, will encounter accuracy and surface roughness mainly the other issues. According to the specific process of turning for analysis.

Mainly the dimensional accuracy of the causes and solutions 1. Because the operator is not careful, measured when the children go awry, or dial it wrong and improper use of the measurement, to carefully and correctly is very important to use the dial , just dial in the carriage handle, the various types of lathe dials are not the same, each small grid scale used the following formula: scale turn a grid pallet screw turning movement distance = distance / dial engraved lines total number of cells (mm) know each grid scale value later, when in use must pay attention because there is a gap between the screw and nut, sometimes turning dials though, but the tools will not necessarily move, and so the gap turn finished before turning movement. Therefore, when in use, the number of cells if the scale turned too far, never allow only a few cells reversed, but to reverse a turn later, and then re-align the scale. (2) there is an error or measuring itself without being put to use measuring tools, you should carefully check and adjust, when used to put positive. 3 due to temperature changes, the change in size of the workpiece during cutting, deformation of the chip, each chip between the respective molecules move against each other, and they move the friction generated when a large amount of heat. In addition, since the chip and the front friction tools, turning tools and the workpiece rear surface of friction generates heat, the heat directly affect up to the tool and the workpiece.

Precision geometry and position of the main reasons mainly the precision 1 causes occurrence of ovality. A. Shaft journal ovality is directly reflected in the work up, if the sliding bearing, then the magnitude and direction when the load is not variable, the spindle neck under load is pressed against the bearing surfaces a predetermined position (between the spindle and the bearing clearance). When the spindle is rotated 90 °, a change in the center of the spindle, so that during one revolution of the spindle has two center position, turning the back there is a change of cut, leaving the workpiece ellipticity. Ellipticity bearing hole of the workpiece has no effect. b. rough uneven margin, plus there is a gap between the spindle and bearings in the cutting process, cutting depth change. c. around the center hole does not match (two center hole at an angle with the workpiece center), the center hole only come into contact with the top side, causing uneven wear axial movement made oval d. former top swing.

Generating the bus is not straight (sterile curved, convex, saddle-shaped) and taper causes a. Lathe spindle axis rail and the mutual position is not correct, in particular in the horizontal. Such as rail bent workpiece convex or concave, rail and the tapered spindle axis is not parallel to produce and so on. b. around the top centerline is not parallel with the bed rail, resulting taper. c. the workpiece temperature, causes the bending axis. For example, in the heavy lathe axis, the temperature rises to a certain time, the workpiece will stretch, but as the distance between centers unchanged, the results could not work because the elongation in the longitudinal direction is bent. Therefore, the long axis of the vehicle, try to lower the temperature, but also must often look back after the top. d. workpiece stress. There is often the stress within the workpiece, the cutting process, due to the plastic deformation of the surface layer, will produce stress, which was the internal stress state of equilibrium inside the workpiece, the workpiece to maintain a certain shape when the lathe work or unloaded from the jig Next, it is necessary deformation. solve this problem, the general aging treatment.

Runout caused by sharp pulsating reasons in the preceding paragraph; center hole is not round or chips and other dirt; course ovality workpiece surface can cause runout.

Mainly the surface roughness of the main one. Lathe less rigid as iron pallet plug loose, drive unbalanced vibrations, of course, is not installed securely lathe will cause vibration, due to vibration caused by the surface roughness is reduced. Turning vibration caused by insufficient rigidity so far as possible use coarse Arbor, projecting a reduced turning length; insufficient rigidity of the workpiece can cause vibration, so the elongated axis turning center rack to be applied, or a folder instead of a two top clamping.

Turning the cutting part geometry parameter is incorrect can be cut according to the workpiece material properties used reasonable and appropriate cutting angle to reduce the surface roughness. 4 due to BUE generation, so that the surface roughness is reduced BUE very strong, cutting the BUE participation, so that the surface appears nap or a tract zoned grooves of the phenomenon, which should be avoided turning production. Combination of the foregoing analysis, the processing should be done early to know early prevention, the problem is nipped in the bud, to improve accuracy of the workpiece to meet the design requirements.

Pebble crushing machine bearing lubricant selection techniques

A rust-resistant for use in bearing grease must have rust, rust inhibitor preferably insoluble in water. Grease should have good adhesion, and can form a film on the steel surface.

2, the mechanical stability of the grease in the mechanical processing will become soft, resulting in leaks. During normal operation, the bearing grease flung bearing. If the mechanical stability of oil is not enough, during operation, make the structure of the soap grease mechanical disintegration, causing oil to be destroyed, and thus loss of lubrication.

3, seal oil seal is required to protect bearings and lubricants from external contamination barrier, bearings during operation, regardless of debris or moisture can not penetrate the bearings, to avoid causing its destruction. Proper installation and maintenance is to play an important factor bearing the longest life. Meanwhile, we must pay attention to the cleanliness of the bearing, bearing selection is correct and choose the appropriate installation and maintenance tools. Further, the bearings must be protected against contamination and moisture contamination and to ensure that there is proper installation and lubrication.

4, mixing oils should never be incompatible greases, if two incompatible greases, usually its consistency becomes soft, it may eventually cause the loss due to bearing grease easily damaged. If you do not know the original use of the bearing grease which one, you must completely remove the old grease bearing inner and outer, before adding new grease.


5, the classification of oils according to the temperature and working conditions distinguished: oils according to their allowable working temperature to the classification, the consistency of grease and lubricating ability is affected by the operating temperature, operating at a temperature of the bearing must be chosen in the same temperatures have the right consistency and good lubrication oil. Fat in a different temperature range manufactured can be broadly classified into low-temperature, medium temperature and high temperature grease used. Meanwhile, there is a class of fats known resistance to crushing or resistance to crushing and adding molybdenum disulfide, at the same time, in which the lubricant with additives to enhance the strength of the film.

6, an important factor in selection grease grease if the wrong choice of bearing all the preventive measures is futile, select a fat, its base oil viscosity at operating temperature to be able to provide adequate lubrication is very important, mainly by the viscosity

Combination Rolling increase spindle speed

In order to meet the rapid development of the machine tool industry, as well as photovoltaic industry micro machining needs, ultra high-speed aerostatic bearing speed now exceeds 3x10e6DN, equivalent shaft surface faster than 150m / s. However, since the bearing clearance between the range 5-20um, at that speed, the air film must have to withstand particularly high shear rate capability. The resulting viscous forces on the bearing thermal and dynamic characteristics have a deadly effect. Loadpoint new design a successful combination with groove rolling series of aerospace bearings overcome this problem.

This new design has been improved so that high-speed operation, it is possible to increase the speed limit and a hard resistance and reduce operating temperatures. Loadpoint new design effectively overcome the main limitation factor that makes aerostatic bearings achieve faster speeds. The aerodynamics and static mechanics combine

Loadpoint combination of the grooved ball bearing - a spiral groove roll neck bearings and a spiral groove thrust bearing, the bearing can be rotated to the center the air squeezed. At high speed, the grooves change this effect can be largely inside the bearing pressure distribution and improve the load capacity and rigidity. Helical groove can also change the speed of the air film inside the bearing and gradient, while reducing the viscosity of the bearing wear. Since the viscosity of air bearing wear and inversely proportional to the area and voids in the same minimum clearance under the combined grooved rolling friction smaller than conventional bearings. The higher the speed, this advantage is more obvious. Rolling and groove combination with traditional aerial bearing performance difference can illustrate this point. . With the increase in speed and the shaft, the bearing lower minimum gap from 28um to 16um. At low speed, the results similar to conventional bearings.

However, when the speed of up to 120,000 rev / min, the band groove bearings have a clear advantage, but also may reach higher speeds. Importantly, the combination of grooved rolling thrust bearing and thrust bearing as conventional, with a static stiffness. However, the function of the groove,

It consumes less energy. Furthermore, the influence of the air force, the hardness increases as the speed increases. However, the conventional thrust bearing not this functionality. That with the combination of the first rolling groove is advantageously within the bore of the grinding spindle with the rotating body. Use of proven, and conventional aviation bearings, rolling bearings with groove combination allows the rotation speed increased by 25% and the current consumption is also reduced by 10%. People also will design a high-speed micro-devices so that the machine spindle diameter is reduced to 50um. Of course, high speed and accuracy as well as running slow calorie reduction are inseparable.