Capacity increase at a cement plant in the Middle East
FLSmidth won the contract for a plant expansion in the Middle East. The contract included, among other things, a new cement mill of OKTM 54-6 type. This type of vertical roller mill is designed for a production rate of 328 tph of cement.
The mill is equipped with a conventional three stage gearbox MAAGTM WPV-5000 from FLSmidth MAAG Gear. It is designed for a drive power of 7800kW and gear ratio of 51:1 reduces the input speed from 995 rpm at the asynchronous motor to the required 19.46 rpm of the mill table. The gearbox has an overall dimension of 5 m in dia. and a height of 3.35 m. With a weight of nearly 200 t it is the largest and most powerful gearbox for vertical roller mills in the world.
After the successful factory acceptance test in the workshop in Elblag, Poland, the gearbox was moved to the cement plant where the installation and commissioning took place in spring 2016. Three months later the concluding load tests under the mill were carried out successfully. With this commissioning FLSmidth reached a new milestone in the field of vertical roller mills and drive systems.
But this new cement mill will not have the largest conventional gearbox for long. A second gearbox, of the same size, for the expansion of an Indonesian cement plant has passed its factory acceptance test in 2015. This gearbox is designed for a type OKTM 56-6 raw mill with a drive power of 8600 kW and a gear ratio of 45:1. The commissioning of this gearbox is expected to be in the nearest future.
Conclusion
The trend towards single mill cement lines is strengthening despite the stagnating global economic situation. The vertical roller mill is the ideal mill type for this application because of its flexibility, low energy consumption and high throughput rates. The vertical roller mill will likely become more important in the future and will gain more market shares.
With increasing throughput rates the power demand of the drive system is also increasing. The recent past shows a cumulation of mills in the power range of 6000 kW to 9000 kW.
The major suppliers for drive systems have developed different new drives for vertical roller mills with high power demand.
With the WPV-gearbox FLSmidth MAAG Gear can provide a unique drive system for the above mentioned mill applications. The high-grade bevel gear in combination with the innovative compound epicyclic gear and an efficient condition monitoring system enables the cement producer to rely on common drive technology for high power application. It makes the implementation of complex control systems for new drive solutions needless.
This is part two of a two-part article written for World Cement’s December issue and abridged for the website. Subscribers can read the full December issue by signing in, and can also catch up on-the-go via our new app for Apple and Android. Non-subscribers can access a preview of the December 2016 issue here.