Gear drives play an important role in the system of load transmission in a production process, and are available in a variety of types, sizes and shapes. In the production process of cement manufacturing, there are many hardware components which have a very important role to play. Moving equipment like rotary kilns, ball mills, roller presses, vertical roller mills, and conveyor belts are a few such examples. All of these use gearboxes and gear drives.
Since the equipment is continuously moving to carry out assigned jobs, the gearbox attached to the equipment requires proper and timely attention for maintenance. Out of these gear drives, the most important and critical gearbox is that of the rotary kiln and next to that, is that of a vertical roller mill.
In fact, the industry across the globe has been trying to identify the reasons for failures of gear drives, and several case studies have been formulated and distributed across the industry. In fact, over the past few years in the Indian cement industry, the incidences of breakdown of gearboxes have come down drastically.
Worldwide, there are very few manufacturers of gearboxes and gear drives. German companies have a strong presence in this domain and companies like Flender and Renk are major suppliers to the cement industry. Particularly, manufacturing a gearbox and gear drive for rotary kilns and vertical roller mills is a super-specialty area and requires understanding of the user industry and the conditions in which the product is set to be used. In-depth knowledge of metallurgy is a basic requirement. The product range of these multinational companies not only includes gearboxes for the cement industry, but also for the automotive, shipping, and power generation businesses.
The first generation of gearboxes for vertical roller cement mills was designed on the basis of a bevel-spur-gear arrangement. The challenge of this design was to balance the ratio of the two-gear stages equally. This allowed keeping the dimensions of the bevel wheel and the spur gear within a manageable range. In order to fulfil the demand of the cement industry, gear suppliers have since chosen a new gear arrangement. The spur gear design has been replaced by a spiral bevel helical with a multi-planetary stage and consequently, it is now possible to reduce the overall dimension and weight of these gear drives, compared to bevel-helical gears.
Actually, a gearbox is a fine piece of sophisticated equipment produced based on the specifications provided by a client, under stringent conditions and strict quality control.