Common Types and Manufacturing Equipment of Mechanical Gears

Gears are the main basic transmission components in the machinery manufacturing industry. Wheeled mechanical parts, which transmit torque by meshing teeth, can realize the functions of changing rotational speed and torque, changing the direction of motion and changing the form of motion by driving with other gear mechanical parts. But for the manufacturing process of high precision gear, especially the gear with many teeth, large diameter, long tooth surface, high precision and long processing cycle, strict process guarantee is required in the hobbing process, and all links such as blank processing, fixture, cutter, machine tool adjustment and environment must be well controlled. Following is a brief introduction to the manufacturing process of automotive gears in Yida Borun Petrochemical Company.

I. Types of Common Gears

Gears can be classified according to the shape of the gear, the shape of the tooth line, the surface of the gear teeth and the manufacturing method.

(1) Gears can be divided into cylindrical gears, bevel gears, non-circular gears, racks, worm and worm gears according to their shape.

(2) Spur gear, helical gear, herringbone gear and curve gear are classified according to the shape of tooth line.

(3) According to the surface of the gear teeth, it can be divided into outer gear and inner gear.

(4) According to the manufacturing method, it can be divided into casting gear, cutting gear, rolling gear, sintered gear and so on.

(5) According to the hardness of gear tooth surface, it can be divided into soft tooth surface gear and hard tooth surface gear.

II. Equipment for Gear Manufacturing

(1) Hobbing machine is a kind of gear hobbing machine, which uses hobs to develop rough, precision straight teeth, helical teeth, herringbone gears and worm gears, so as to achieve higher accuracy and efficiency.

(2) Gear shaping machine is used to cut spur, helical gear and other teeth by generating method with gear shaping cutter. It is mainly used for multiple gears and internal gears.

(3) The gear milling machine is milling by indexing method with forming milling cutter, which is mainly used for instrument gears with special tooth profile.

(4) Shaving machine is a kind of efficient machine tool which uses gear shaving cutter to finish gears.

(5) Grinding machine is a high-precision machine tool with grinding wheel, precision hardening cylindrical gear or gear cutter tooth surface;

(6) Honing machine is a machine which uses the free meshing between the honing wheel and the gear to eliminate the burr of hardened gear and other tooth surface defects.

(7) The extruder is a machine tool which uses the free meshing of the extruder with high hardness and no cutting edge to smooth the slight unevenness on the tooth surface, so as to improve the accuracy and smoothness.

Selection of Cutting Oils

(1) Silicon steel is a relatively easy-to-cut material. Generally, in order to clean the finished gear workpiece easily, low-viscosity gear cutting oil will be selected on the premise of preventing burrs.

(2) When choosing cutting oil for carbon steel gear cutting, the better viscosity should be determined according to the process difficulty and degreasing conditions.

(3) Because galvanized steel and chlorine additives will react chemically, attention should be paid to the possibility of white rust of gears when choosing gear cutting oil. Rust can be avoided by using Yida Borun sulfur-type special gear cutting oil, but degreasing should be done as soon as possible after processing.

(4) In the cutting of stainless steel gears, the gear cutting oil containing sulfur-chlorine compound additives is generally used to ensure the extreme pressure performance, while avoiding burrs and cracks in the workpiece.

These are the common types of gear and gear manufacturing equipment. Rational selection of gear manufacturing equipment can effectively reduce investment and improve efficiency.