Silicon Nitride Ceramic (Si3N4)–Ideal Raw Material of Bearing

With the development of mechanical manufacturing industry towards high precision and high speed, the application range of bearings is more and more wide, and the performance requirements of bearings are also higher and higher, especially in some special working environment, metal bearings can not adapt to the demand, or even can not work at all. Because of its low density, high modulus of elasticity, low coefficient of linear expansion, wear resistance, high temperature resistance, corrosion resistance and other excellent properties, ceramic material has become an ideal material for high-speed manufacturing of precision bearings. Advantages and Characteristics of Silicon Nitride Ceramics Although silicon nitride is not the hardest and the most tough material in industrial ceramics, it is considered to have the best mechanical and physical properties in high performance bearing applications. Heat ResistanceGenerally, when the service temperature of steel bearings exceeds 120 ℃, the hardness will decrease and the rolling life will also decrease. Silicon nitride has good temperature characteristics, especially suitable for high temperature environment. Centrifugal ForceThe density of silicon nitride is about 3.24 × 103kg / m3, while the density of bearing steel is about 7.8 × 103kg / m3, which is only about 40% of the density…

Things you should know about “Bearing Pretightening Mode” & “Bearing Stiffness”

Bearing is an important part of mechanical rotation, and its stiffness and working temperature will directly affect the bearing efficiency on the mechanical operation. In order to provide the rotation accuracy of the bearing, increase the rigidity of the bearing device, and reduce the vibration of the shaft when the machine is working, the preloaded rolling bearing is often used, such as the spindle bearing of machine tool. The bearing stiffness is the force required to produce a unit deformation. The elastic deformation of rolling bearing is very small, which can not be considered in most machines. However, in some machines, such as machine tool spindle, bearing Stiffness is an important factor, in which case generally cylindrical roller bearings and tapered roller bearings should be selected. Because these two kinds of bearings are in line contact with the raceway when they are under load, they have small elastic deformation and good stiffness. All kinds of bearings can also be preloaded to increase the support stiffness. Such as angular contact ball bearing and tapered roller bearing, in order to prevent shaft vibration and increase support stiffness, a certain axial force is often applied in advance during installation to make them compress…

Quick Guide to Powdered Metals and Their Uses

Powder metallurgy (PM) is a technology that uses metal powder or nonmetal powder or its mixture as raw materials to manufacture metal materials, composite materials and various types of products through forming and sintering. Its three core elements are technology, materials and equipment, which are widely used in transportation, machinery, electronics, aerospace and other important industrial fields. It is the most potential and dynamic branch of new materials science.

Slewing Bearing Application

Slewing bearings usually have a diameter ranging from 0.2 to 10 meters. They consist of mounting holes, internal or external ring gears, lubricating oil holes, and sealing devices. The mounting holes are divided into through holes and threaded holes. Different for different industries The slewing bearing has a variety of structural types to meet its requirements, and can meet the needs of the main engine function with different manufacturing accuracy levels. Therefore, the slewing bearing is an indispensable machine on the slewing device of medium and large construction machinery slewing bearing. component. It plays an important role in the machinery industry, construction industry, coal industry and shipbuilding industry. The slewing bearing has toothless type, external tooth type and internal tooth type. The structure types slewing bearing generally include single-volley, double-volley, cross-roller, three-row roller, ball-column combined and other forms, of which single-row ball The slewing bearing has a relatively low cost and excellent overall performance. The double volleyball slewing bearing has certain advantages in service life, strong bearing capacity, small swing resistance, large allowable wear, and strict requirements for the mounting base. Raceway rotation accuracy is low; Crossed roller slewing bearings have high accuracy, long life, and high dynamic load capacity, but have high…

Slewing Bearing – Part 01

Slewing Bearing, also known as slewing ring bearing, turntable bearing, slewing ring, etc, is widely used in modern industries. Types of Slewing Bearing Single-row ball type (01 series, HS series, Q series)Double-row ball type (02 series)Three-row roller type (13 series)Single-row cross roller type (11 series)Double-row ball type (07 series) )Light and non-standard specifications series slewing bearing Manufacturing Processing Raw material inspection Chemical composition analysis Heat treatment Raceway hardness inspection Gearing processing Gear inspection CNC drilling processing Mounting hole inspection Turning processing Raceway inspection Assembly Finished product inspection Qualified stock In the entire cycle of slewing bearings from forgings to finished products to the hands of customers, the tooth processing technology takes the longest time, and the length of the delivery period depends greatly on the timeliness of the slewing gear processing. Hobbing machining accounts for about 45% of the entire slewing bearing processing volume, or even a larger proportion. For large diameter and large modulus slewing bearing machining, milling gear machining also reflects the characteristics of good machining accuracy, high efficiency, and convenient programming. In recent years, in order to adapt to the improvement of machining precision and production efficiency requirements of slewing bearing processing, the hobbing technology has continuously…