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NTN Needle roller bearing
- Category: Needle roller bearing
- Description:The NTN needle roller bearing is equipped with a thin and long roller (3~10 times the diameter of the roller,...
- Email:admin@jngybearing.com
- TEL:+86 15165026537
- Company:Ji'nan Guang Yue Pml Precision Mechanism Ltd Of China
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The NTN needle roller bearing is equipped with a thin and long roller (3~10 times the diameter of the roller, and the diameter is generally not more than 5mm), so the radial structure is compact and its inner diameter and load capacity are at the same time as other types of bearing, and the outer diameter is the smallest. It is especially suitable for the bearing result of the restricted radial installation size. The roller bearing is used according to the use. In different occasions, the bearing or needle roller and the cage assembly are selected without inner ring. At this time, the surface of the shaft neck and the outer surface of the shell are directly used as the inner and outer rolling surface of the bearing. It is the same as the bearing ring bearing, the hardness, the machining accuracy and the surface quality of the shaft or the casing hole raceway surface. The use combination roller bearing is a bearing unit composed of the centripetal needle roller bearing and the thrust bearing. Its compact structure is small, the rotation precision is high, and it can bear a certain axial load while bearing a high radial load. Moreover, the product has various forms, wide adaptability and easy installation. Combined needle roller bearings are widely used in machine tools, metallurgical machinery, textile machinery and printing machinery and other mechanical equipment, and can make the design of the mechanical system very compact and dexterous.
Characteristics of NTN inlet bearing
Because of the characteristics of NTN imported bearing steel, the requirement for smelting quality is much stricter than that of general industrial steel, such as the chemical composition, purity, structure and structure uniformity of steel.
First, strict chemical composition requirements
General NTN imported bearing steel is mainly high carbon chromium bearing steel, that is, carbon content is about 1%, adding about 1.5% of chromium, and contains a small amount of manganese and silicon elements of the eutectoid steel. Only by strictly controlling the content of the chemical elements in the imported bearing steel of NTN can the microstructure and hardness of the NTN bearing be obtained through the heat treatment process.
Second, strict and high precision size requirements
Rolling bearing steel requires high dimensional accuracy, because most of the NTN imported bearing parts are subjected to pressure molding. In order to save the raw material and improve the productivity, most of the NTN imported bearing rings should be forged and formed. The steel ball is cold heading or hot rolling, and the small size roller is also formed by cold heading. If the precision of the steel is not high, the size and weight of the material can not be calculated accurately, which can not guarantee the quality of the NTN imported bearing parts and the damage of the manufacturing equipment.
Third, especially strict requirements for purity
The purity of steel refers to the amount of impurities contained in steel. The higher the purity, the less the non-metallic inclusions in the steel. The contents of harmful impurities such as oxides and silicate in bearing steel are greatly related to the early fatigue peeling of NTN imported bearings and the decrease of the life of NTN bearing. Especially brittle impurities are most harmful, because it is easy to peel off the metal matrix in the process of processing, which seriously affects the appearance quality of the NTN imported bearing after finishing.
Fourth, strict tissue and microscopic (high power) tissue requirements.
The low fold structure of bearing steel refers to the general looseness, the center loose and the flat analysis. The microstructure (high times) of the microstructure includes the annealed structure of steel, the mesh of carbide, the strip and the liquid analysis. Carbide solution is hard and brittle, and the damage is the same as that of brittle inclusion. The network carbide reduces the impact toughness of the steel and makes the microstructure uneven, and it is easy to deform and crack during quenching. Zonal carbides affect annealing and quenching tempering structure and contact fatigue strength.
Fifth. Strict requirements for external defects and internal defects.
For NTN imported bearing steel, the external defects include cracks, slags, burrs, scars, oxide skins and so on. Internal defects include shrinkage, bubbles, white spots, serious porosity and segregation. These defects have a great influence on the processing of bearing, the performance and life of NTN imported bearings, and it is clear that these defects are not allowed in the specification of NTN imported bearings.
Sixth. Particularly stringent requirements for carbide inhomogeneity
In the imported bearing steel of NTN, if the serious carbide distribution is not uniform, the uneven microstructure and hardness will be caused in the process of heat treatment, and the unevenness of the steel has a great influence on the contact fatigue strength.
Seventh, specially strict surface decarburization requirements
In the specification of NTN imported bearing data, there are strict regulations on the decarburization layer of steel appearance. If the surface decarburization layer does not conform to the standard range and does not remove all of them during the process of heat treatment, the quenching crack will occur easily during the process of heat treatment and quenching, resulting in the scrap of the parts.
Eighth. Other requirements
The bearing steel material specification also has strict requirements for bearing steel smelting method, oxygen content, annealing hardness, fracture, residual element, spark inspection, delivery state, marking and so on.
NTN needle roller and cage assembly
The NTN needle roller and cage assembly is easy to install and use, and the needle will not fall off if the needle is installed. The occupied space is small, but has great bearing capacity. Because the cage structure is unique, it can accurately guide needle roller and lubricate ideal, so it can be used at high speed. The rolling needle bus has crown, which can ease the stress concentration of the needle end caused by the minor installation error and the deformation of the shaft, and prolong the service life of the bearing.
NTN punching outer ring roller bearing
NTN punching outer ring roller bearing (with the cage type and full mounted roller type) has a unique outer ring structure. It is a kind of bearing with a large number of special lengths in the rolling bearing. These features include the thinnest wall thickness of the outer ring and the large load capacity; it is made of a specially selected special alloy steel plate, with a high limit load; maintained. The frame is treated by surface hardening, with strong abrasion resistance, high speed limit and easy installation.
NTN solid needle roller bearing
The solid roller bearing has high precision, small occupied space and strong bearing capacity. Its application is very extensive.
The rings are made of strictly selected vacuum degassing bearing steel or carburized steel after heat treatment. There are many high precision needle rollers with a certain degree of convexity in the outer ring with strong double sides.
The cage is light in weight and strong in toughness. It can accurately and steadily guide the needle with large diameter.
NTN thrust needle roller bearing
Thrust needle roller bearings, made of rice and English.
The cage in the thrust needle and cage assembly is buckled by 2 semi cage, which is punched by steel plate and hardened by surface hardening. The high-precision needle is assembled into the cage to make it have high strength and abrasion resistance. The needle is completely retained by the cage, which can bear a large axial load and rotate smoothly at the same time. Moreover, the assembly space is small, and it is easy to replace the original thrust washer (the same name as the shaft ring and the seat ring). The needle roller and the cage assembly are equipped with a number of different thrust washer with different thickness, so the thrust washer can be selected according to the assembly conditions around the bearing.
NTN bolt bearing roller bearing
The bolt bearing roller bearing, the outer ring wall thickness, the needle roller busbar with the convexity, the double head bolt on the raceway surface after hardening treatment, has a certain toughness, can withstand the impact load.
NTN ring roller bearing
The retaining ring type roller needle roller bearing has thick outer ring, rolling needle bus has convex degree, high load capacity, and can withstand impact load. This kind of bearing is non separable, easy to use and widely used in rollers, cams, rocker arms and so on.
