Bogiflex KGD (Kiln Gear Drive)

By introducing the Bogiflex KGD (Kiln Gear Drive), CMD’s aim is to make the drive system an integral part of kiln performance by enhancing its reliability and performance.

Kiln running behavior greatly impacts the running conditions of the pinion and girth gear. Deformation of the kiln shell is prone to modify the girth gear geometry which led CMD to develop a completely new solution, to solve the listed issues.

The Bogiflex is a floating and self-aligning gearbox. It follows the movement of the girth gear, and therefore kiln shell, in every direction. It compensates for any kiln deformation or movement and ensures that pinion-girth gear meshing conditions are always constant. The CMD Bogiflex KGD components include standard components and therefore allow commonality of spare parts between several plants. The tuning of the drive reduction ratio is obtained by adjusting the specification of the primary gearbox. Three standard sizes of Bogiflex KGD units exist so far which cover most existing kiln sizes.

Table 1: Bogiflex KGD range

KGD size Kiln shell Max driven torque at the shell (Nm)
KGD20  <4.6 1,000,000
KGD26  4.6-5.2 2,300,000
KGD32 >5.2 >4,000,000

Bogiflex Benefits

Some of the obvious benefits brought by the Bogiflex concept are:
• constant position of the pinion to the girth gear and, therefore, constant meshing conditions and excellent load repartition on the pinion and gear teeth
• a direct consequence is the increase of pinion and girth gear life
• reduction of shutdown risk thanks to stable working conditions
• no more pinion alignment required.
The globalisation and standardisation of the concept also bring other advantages:
• safety of the integrated oil circulation systems
• integrated monitoring system (for vibration, temperatures, optional monitoring of torque available)
• standardised spare parts, which can be shared between several plants
• reduced foundations requirement (the
Bogiflex itself is only supported by a reaction arm), which allows its use for new kilns as well as for the replacement of existing drives.
These technical advantages make the Bogiflex KGD solution a cost-effective system as well as demonstrated by the net present value (NPV) calculation carried out by our customers.