The Development Trend and Material Selection of Drum Gear Coupling

The development trend of drum gear couplings The drum gear coupling is a new type of gear coupling based on the spur gear coupling and digesting and absorbing technology.It is composed of an outer gear sleeve with a drum-shaped tooth thickness and a matching inner gear ring that connects two shafts. It is suitable for heavy load and two-axis transmission that requires axis displacement compensation.Under normal circumstances, it is required that the two shafts to be connected are concentric, and it is impossible to continue to maintain the concentric state during operation. Because of installation errors, bearing wear, force deformation, foundation sinking, etc., the axis produces radial and angular axis. To displacement.The drum gear coupling has the characteristics of compensating the above displacement, reduces the additional load caused by the axis displacement, improves the working stability and performance of the transmission device, and thus prolongs the service life of the transmission device.In recent years, drum-shaped gear couplings have been widely used in many industries in my country, from high-speed turbine units to medium and low-speed heavy metallurgical, mining, lifting and transportation equipment, and a large number of applications have also formed their own standard series. They have also accumulated rich experience in all aspects.

1. The technical level and current status of the product. Drum gear couplings have caught up to the level in my country in terms of product specifications, performance parameters, and manufacturing accuracy.

1.1产品标准主要参数在   ：德国FLENDER公司的标准系列：   大回转直径1710mm；公称   大转矩4030kN.m。德国TACKE公司的标准系列：其   大回转直径1760mm；公称转矩3550kN.m。日本三菱株式会社标准系列：其   大回转直径1644mm；公称转矩4400kN.m。在我国八十年代制定了      标准：ZBJ19012-89,ZBJ19013-89,ZBJ19014-89,现在修订为：JB/T8854.1-2001,JB/T8854.2-2001,JB/T8854.3-2001；其   大回转直径1644mm；公称转矩4500kN.m。

1.2影响接触强度的齿面曲率半径和齿啮合角鼓形齿式联轴器承载能力和寿命取决于接触强度,而齿面曲率半径和齿啮合角则直接影响接触强度,下面就齿啮合角和曲率半径与接触强度的关系式于下：—接触应力F—齿轮承受的圆周力E—材料弹性模量—齿面曲率半径—位移圆半径—啮合角—内外齿啮合高度从上述式中我们看到齿面曲率半径和齿啮合角直接影响接触应力,啮合角小曲率半径大,曲率半径大则接触应力小。在   鼓形齿式联轴器的啮合角有20°、21.5°、28°、30°。我们选用20°啮合角，有利降低接触应力。

1.3 Manufacturing technology Drum-shaped gear bushing tooth profile processing, from manual, electric pulse, hydraulic profiling to comprehensive CNC processing in China, the accuracy can meet the design requirements.Nitriding treatment can be carried out when hard tooth surface is required, or low-carbon alloy steel can be used for carburizing and quenching and grinding or scraping with an alloy knife to meet the design requirements.

2. Development trend With the continuous development of technology, there are more and more drum-shaped gear couplings that require heavy-duty hard tooth surfaces.The main parts of the heavy-duty drum gear coupling are made of low-carbon alloy steel, which is milled and ground after heat treatment, with high machining accuracy, and the heat treatment carburized layer is controlled by numerical control equipment.The drum-shaped gear coupling used by SMS company in the main drive mechanism of the rolling mill, the main material is 15Cr2Ni2 or 17Cr2Ni2Mo, and the tooth surface is ground.From the above two perspectives, the development of the hard-toothed drum gear coupling requires us to further improve the manufacturing process and equipment.The requirement of the interchangeability of the main parts of the drum gear coupling is worthy of our attention: the parts of each specification in the drum gear coupling can be interchanged. If one of them is damaged, it can be replaced with a single spare part. It does not need to be replaced as a whole, which saves maintenance time and is convenient for users.In my country, the drum-shaped teeth with hard tooth surfaces are generally nitrided, and the hardened layer has a small service life, which is not ideal. In recent years, the Erzhong Group Company and the Erzhong Basic Parts Factory have successfully developed carburized and ground Hard tooth surface drum-shaped gear coupling, the product is used by Baosteel, Tianjin Steel Pipe Company, etc.The problem of parts interchange: Due to the manufacturing cost, we use CNC machine tools to meet the requirements of users if they have requirements. However, from the perspective of the development situation, the interchangeability of product parts will be required regardless of the user's requirements.

3. Production and sales status and market forecasts. In the 1s, drum gear couplings were developed and standards were formulated. Machinery industry standards have been published and implemented for nearly two decades. They have basically replaced the original spur gear couplings. Compact structure, large load capacity, small moment of inertia, and axis offset compensation performance, so it is widely used in various types of mechanical transmission, coupled with the coupling itself is a wearing part, it needs to be replaced every 2 to XNUMX years Therefore, the market demand is large. The annual sales of drum gear couplings in Deyang alone are more than XNUMX million yuan. It is estimated that the annual demand for domestic machinery, metallurgy, and heavy lifting and transportation is not less than XNUMX million yuan. Manufacturers increase technical input, new equipment, and produce drum-shaped gear couplings as soon as possible in the market, and make due contributions to the development of China's technology.In view of the requirements for the use of drum gear couplings, reasonable materials and heat treatment processes should be used respectively to have the performance of the coupling, which can meet the design requirements!