Industry dynamic
Machine tool industry demand for bearings
The use of rolling bearings in machine tools is mainly used in the following three parts: spindle, ball screw and general drive shaft.
Spindle bearing, as a basic part of machine tool, its performance directly affects the machine tool's speed, rotary accuracy, rigidity, anti-vibration cutting performance, noise, temperature rise and thermal deformation, and then affects the precision of machining parts, surface quality, etc. Therefore, high-performance machine tools must be matched with high-performance bearings.
The precision of rolling bearings is generally divided into FIVE grades: P0, P6, P5, P4 and P2. The precision of bearings on the spindle of precision machine tools should be P5 and its superior, while for the spindle support of high-speed and high-precision machine tools such as CNC machines and machining centers, P4 and its superior ultra-precision bearings should be selected.
Machine tool spindle bearings usually include deep groove ball bearings, angular contact ball bearings, cylindrical roller {TodayHot} sub-bearings, two-way thrust angular contact ball bearings, tapered roller bearings and thrust bearings and other six structural types.
With the rapid development of numerical control technology, "compound, high-speed, intelligent, precision, environmental protection" has become the main trend of the development of machine tool industry technology. Among them, high speed machining can effectively improve the machining efficiency of machine tool and shorten the machining cycle of workpiece. This requires the spindle and its related components to adapt to the needs of high-speed machining. At present, CNC machine tool spindle bearings are basically limited to angular contact ball bearings, cylindrical roller bearings, two-way thrust angular contact ball bearings and tapered roller bearings and other four structural types.
With the high-speed development of CNC machine tool spindle, ceramic materials (mainly refers to Si3N4 engineering ceramics) because of its small density, high elastic modulus, small thermal expansion coefficient, wear resistance, high temperature resistance, corrosion resistance and other excellent properties, so as to become the ideal material for manufacturing high-speed precision bearings. Ceramic bearings are more and more widely used. In view of the difficulty of machining ceramic materials, precision ceramic bearings are mostly mixed ceramic ball bearings whose rolling body is ceramic and whose inner and outer rings are still made of chrome steel.
Ball screw pair as precision, efficient and sensitive transmission components, in addition to the use of high-precision screw, nut and ball, should also pay attention to the selection of high axial stiffness, small friction torque, high precision bearings. Ball screw support in the past commonly used two-way thrust angular contact ball bearings, tapered roller bearings, needle roller and thrust roller combined bearings, deep groove ball bearings and thrust ball bearings. At present, ball screw support is more used in 60° contact Angle single row thrust angular contact ball bearings, and the accuracy grade is mainly P4 and its superior.
The rolling bearing installed on the general drive shaft for machine tools has the same requirements and selection as the ordinary mechanical drive bearing. It only needs to meet the requirements of strength and life, and the speed does not exceed the specified bearing limit speed.
In general, the machine tool bearings we refer to refer to the machine tool spindle bearings and ball screw bearings, precision machine tool bearings refer to the accuracy of P5 and P5 to the higher spindle bearings and screw bearings.
Spindle bearing, as a basic part of machine tool, its performance directly affects the machine tool's speed, rotary accuracy, rigidity, anti-vibration cutting performance, noise, temperature rise and thermal deformation, and then affects the precision of machining parts, surface quality, etc. Therefore, high-performance machine tools must be matched with high-performance bearings.
The precision of rolling bearings is generally divided into FIVE grades: P0, P6, P5, P4 and P2. The precision of bearings on the spindle of precision machine tools should be P5 and its superior, while for the spindle support of high-speed and high-precision machine tools such as CNC machines and machining centers, P4 and its superior ultra-precision bearings should be selected.
Machine tool spindle bearings usually include deep groove ball bearings, angular contact ball bearings, cylindrical roller {TodayHot} sub-bearings, two-way thrust angular contact ball bearings, tapered roller bearings and thrust bearings and other six structural types.
With the rapid development of numerical control technology, "compound, high-speed, intelligent, precision, environmental protection" has become the main trend of the development of machine tool industry technology. Among them, high speed machining can effectively improve the machining efficiency of machine tool and shorten the machining cycle of workpiece. This requires the spindle and its related components to adapt to the needs of high-speed machining. At present, CNC machine tool spindle bearings are basically limited to angular contact ball bearings, cylindrical roller bearings, two-way thrust angular contact ball bearings and tapered roller bearings and other four structural types.
With the high-speed development of CNC machine tool spindle, ceramic materials (mainly refers to Si3N4 engineering ceramics) because of its small density, high elastic modulus, small thermal expansion coefficient, wear resistance, high temperature resistance, corrosion resistance and other excellent properties, so as to become the ideal material for manufacturing high-speed precision bearings. Ceramic bearings are more and more widely used. In view of the difficulty of machining ceramic materials, precision ceramic bearings are mostly mixed ceramic ball bearings whose rolling body is ceramic and whose inner and outer rings are still made of chrome steel.
Ball screw pair as precision, efficient and sensitive transmission components, in addition to the use of high-precision screw, nut and ball, should also pay attention to the selection of high axial stiffness, small friction torque, high precision bearings. Ball screw support in the past commonly used two-way thrust angular contact ball bearings, tapered roller bearings, needle roller and thrust roller combined bearings, deep groove ball bearings and thrust ball bearings. At present, ball screw support is more used in 60° contact Angle single row thrust angular contact ball bearings, and the accuracy grade is mainly P4 and its superior.
The rolling bearing installed on the general drive shaft for machine tools has the same requirements and selection as the ordinary mechanical drive bearing. It only needs to meet the requirements of strength and life, and the speed does not exceed the specified bearing limit speed.
In general, the machine tool bearings we refer to refer to the machine tool spindle bearings and ball screw bearings, precision machine tool bearings refer to the accuracy of P5 and P5 to the higher spindle bearings and screw bearings.