Four-Point Contact Ball Bearing
Bearing knowledge / 2020-04-23

Design Variants To allow the bearings to accept the maximum number of balls, four point contact ball bearings are designed with split inner ring or with split outer ring so these bearings have two basic types, one is featured two half inner ring(QJ series), the other is featured two half outer ring(QJF series). TBB four point contact ball bearings have the contact angle of 35°. We can both provide QJ series and QJF series on request. TBB four point contact ball bearings with outer ring diameters of more than φ160mm are produced with two locating slots in their outer ring (suffix N2), we can also provide small size of outer diameter within φ160mm with locating slots. Tolerance TBB four-point contact ball bearings are produced to the normal tolerance class (PN or P0) as standard. Other tolerance classes such as P6 or P5 are available on request.  ​Cages TBB four-point contact ball bearings are fitted with outer ring centred solid brass cage (suffix MPA or MA, MPA-Solid window cage, guidance by the outer ring, it is the most common type; MA-Solid brass cage, guidance by the outer ring) as standard, please refer to the picture left. Internal Clearance TBB four-point contact…

Bearings World from Figures
Bearing knowledge / 2020-04-13

Size from 2mm to 6m Bearings vary in sizes. The smallest “miniature bearing” in the world is with ID 0.6mm× OD 2.0mm× Thickness 0.8mm, which is used in micro motor. The large-size bearing, with an outer diameter of 6m and a weight of more than 15 tons, is used in the large shield machine for tunneling. This kind of large bearing is used when excavating the cross sea tunnel under the Dover strait connecting Britain and France.  400,000 rpm The dental drill used by dentists (commonly known as dental mobile phones) is equipped with bearings that can rotate at ultra-high speed. It uses two ultra precision bearings with inner diameter of 3.0mm × outer diameter of 6.0mm × width of 2mm and steel ball diameter is of 1.0mm. They can rotate at an amazing speed of 400,000 rpm, which greatly reduces the vibration of dental mobile phones, thus greatly reducing the pain of patients during treatment.  Ball Speed 160 m/s The main shaft bearing of jet engine V2500 of international airliner has a rolling speed of 160 m/s, equivalent to 580 k/h. It is because of using this high-performance high-speed bearings that the engine can run safely for a long…

PWM Frequency Modulation Motor Bearing

With the wide application of PWM and IGBT in motor, the problems caused by electromagnetic damage such as electric corrosion of bearing are more and more prominent. What causes electromagnetic damage of bearing? Common mode voltage is the main cause electromagnetic damage. When the bearing is running at high speed, there will be a fluid oil with strong insulation between the roller and the inner & outer raceways. Due to the constant change of common mode voltage, fluid film is charging and discharging, leading to currents. It has a continuous thermal effect on the lubricant, which will cause deterioration, deficiency, carbonization of lubricant, thus affecting the life of bearing. Under the deficiency of lubricant, the shaft current directly passes through the bearing and discharges on the contact surface of the bearing, which will cause teeth electric erosion along the rolling direction. When the common mode voltage on both sides of the fluid film is too large, the fluid film will be broken down, resulting in EMD currents. It will cause electrical erosion pits on the raceway, which usually need to be observed under the microscope. And the raceway appears dim and tarnished. Solution In PWM Frequency Modulation Motor, EMD current…

The Meaning of the Preload of Crossed Roller Bearings
Bearing knowledge / 2020-03-23

What is the preload of crossed roller bearings? Generally, rolling bearings have a certain clearance under working conditions. However, in order to achieve a specific purpose, when the cross roller bearing is assembled, apply a certain internal load through adjustment of the clearance to achieve negative clearance. This method is called preload. What are the benefits of preload of crossed roller bearings? 1.Improve the Rotation Accuracy After the bearing is pre-loaded, the internal clearance is eliminated, and each rolling element is subjected to a certain preload, so that the cross roller ring is supported from all directions. Therefore the running accuracy is improved, and the shaft will be positioned correctly in the axial and radial directions. 2. Increase Stiffness The contract between the rolling element and the raceway is elastic contact. The rolling element can be regarded as a spring. Bearings with clearance are supported by only a few springs in the direction of force. But the pre-loaded cross roller bearings are spring-loaded in all directions and have a certain amount of preload. The number of rolling elements under load is greater than that when there is a clearance, so the stiffness can be improved. 3.Extend Bearings Service Life After…

Bearings Rust Easily
Bearing knowledge / 2020-03-16

Since bearings are metallic products they rust easily. So their treatment requires certain precautions. 1. When handling bearings, use finger caps, pincers or gloves that do not generate cotton fibers. 2. When you must use naked fingers, first make sure they are clean and free from perspiration and dust. Then apply a quality mineral oil to the fingertips before touching the bearings. Do not use hand cream, as it may induce rust. 3. If a shaft is dirty on the surface, rust may gather between the shaft and the bearing after they are fitted. So it is important to make certain the shaft is free from finger prints and perspiration. 4. When handling bearings choose a place that is dry. Always place the bearing boxes on a shelf or pallet. Avoid placing the boxes directly on the floor or other locations where moisture and dirt may be present. 5. Avoid storing bearings near air conditioners and direct sunlight. Bearings may rust when placed near an air conditioner outlet or any place where wind or sunlight can enter directly. 6. A great temperature variance may cause condensation to form on bearings. In colder climates allow the bearings to reach room temperature…

Bearings Don’t Like Particles
Bearing knowledge / 2020-03-09

The performance of ball bearings can be critically affected by minute particles. Particles as small as 0.005mm can cause problems. To prevent such problems, we use a class 1,000 clean room throughout our bearing assembly operation. “Keeping bearings clean” is the most important rule of bearing use. Avoid exposing bearings to any environment where particles may be present. Once inside a bearing, such particles can cause raceway scratches, abrasion and shortened life. They can also generate acoustic noise and vibration. We use shields or seals to keep particles out. But there is still a gap between the shield and inner ring of shields and non-contact seals. This gap may permit particle entry. So it is important to observe the following procedures carefully. 1. Keep your bearing handling area as clean as possible. 2. Do not remove the bearings from their packaging until just before use. If you move the bearings to a container, be sure the container is clean. Its lid should be kept closed and it should be cleaned every day to prevent particle accumulation. 3. Never use a bearing that has been dropped. It may be brinelled (race track dented). In use, a brinelled bearing will generate a…

Our current price is 50% lower than yours…

After offering we heard many times voice of “Your price is too high” or “Our current price is 50% lower than yours ” …You have explained to customer that how good quality your product is, showed your testing reports with thousands times, because you know clearly the difference between products of different price level. How do you prove it? Yes, taken inspection for these different products is a good method . TBB did so.However, the testing of basic data such as size, clearance, precision, vibrate. Sometimes there have very big different on measurement, but sometimes there do not have very obvious different on data. What is the deep reason for big price gap? To end the confusion, TBB did further testing- Life Reliability Comparison Test at National Bearing Testing & Inspection Institute.A group of 4 piece of deep groove ball bearings, after rigorous and reasonable experimental process: Firstly, can you guess how the bearings performed ? Here comes some pictures to show how it performance. Secondly, can you guess how many hours the bearings lasting? Here comes the testing results. #1 bearing from TBB OEM product, it lasting for 121.5 hours till the testing ended with good condition.#2 bearing from world well-known second-class…

Gearboxes

Gearboxes are used in a very wide range of industrial fields. Thanks to the use of gearboxes, a small rotation force (torque) can be used to produce a much greater rotation force, and a slow rate of revolution can be speeded up. In many industries, the gearbox, which is the equipment that transmits mechanical power, is an essential piece of equipment. This step-up unit is the: heart of a wind turbine transmission in an automobile the reduction gears in a Ferris wheel By supplying bearings for gearboxes such as these in support of their most important function: “revolving,” we believe that it can even be said to be supporting the world. However, because there are many instances where the breakdown of a gearbox would have serious implications, extremely high reliability is demanded. Naturally, we seek to ensure that its designs closely match customer needs, and the company is always aiming to enhance product quality. We supply bearings that offer long life to reduce equipment maintenance costs, can handle high load capacities, and are extremely reliable. We will continue to pool our comprehensive strengths. With environmental issues firmly in its sights, our company will continue product development efforts so that it…

Bearings with black oxide finish – Increased performance in critical applications

At this year’s Hannover Messe in Germany, bearing manufacturer NKE Austria GmbH presents bearings with black oxide finish. The protective layer improves run-in and wear characteristics and protects against environmental effects. Especially in critical applications such as wind turbine gear boxes, black oxide finish is a cost-effective and technically viable means of prolonging the service life and performance of rolling bearings. The black oxide finish forms a protective layer for steel parts. In a multistage chemical process, the surface layer of the treated parts is converted into a 1 to 2 micrometer thin mixed ferrous oxide layer that causes the characteristic black appearance. Black oxide finished bearing components feature a set of special technical characteristics, especially in the case of components that move relative to each other. Multiple protective effects can be achieved if only one functional element (typically the rolling elements) is treated. For best effect, however, all functional surfaces of a rolling element bearing, including the inner and outer ring as well as the rolling elements, should be black oxide finished. Black oxide finishing is already an established method in other industries. NKE uses this technology to further improve the technical properties of rolling bearings. The method has…

Drawn Cup Needle Roller Bearings

TBB drawn cup needle roller bearings is formed with thin steel plate through precision punching with very sectional height and big load capacity. This kind of bearings are especially applicable to the big quantity production with economic demands. Stable combination is used between the needle bearings and the bearing cage. No axle fixture is required. Even under high speed and heavy load condition, the bearing functions can be fully maintained. Furthermore, no lubricating for a long time is possible due to its high storage volume of grease. Structure Types Mounting The outer ring of the drawn cup needle roller bearings made of thin steel plate through punching will reach the correct shape and dimension precision when it is pressed into the bearing cage. Therefore, the dimensional precision and the shaped of bearing cage will directly effect the inscribed circle of the bearing. Thus enough attention must be attached to the size and shape of the bearing cage. In mounting this kind of bearings, it will be easier to use the pressing core shaft as illustrated in the figure. Special tool must be used to press on the side with printed code mark to compress get the bearings fitted when assemblying….