Key Benefits

  • Longer lifespan
  • Higher efficiency
  • Fewer spare parts
  • Shorter installation time

The Unax Cooler offers an improved planetary cooler design

Despite the improvements of modern grate cooler technology, it is crucial to have a cooling system that offers better affordability. That’s why FLSmidth has developed the Unax Cooler, a planetary cooler that keeps simplicity, durability, and reliability as top priorities. 

With installations dating back to 1967, we have used our expertise and experience to create a new generation of internal fittings that improve on older versions of the Unax Cooler. The rising costs of energy and labour combined with the development of more suitable materials and casting techniques both necessitate and enable better designs of planetary cooler internals, which is exactly why the Unax Cooler aims to be more affordable than other coolers on the market.

A planetary cooler is attached rigidly to a rotary kiln and rotates with it. This is unlike a rotary cooler, which is attached at a level lower than the kiln, resulting in higher maintainability costs, as the kiln itself needs to be positioned higher than the cooler on expensive foundations. There are more moving parts in a rotary cooler which can increase maintenance costs compared to a Unax Cooler which is attached to the kiln meaing only one drive system.

With its improved design, our Unax Cooler is bound to produce satisfactory results.

Benefits that provide a simpler and more efficient experience

Our improved Unax Cooler design offers many benefits, all of which aim to increase the simplicity of its use, while also boosting its reliability and efficiency.

Longer lifespan
With the new features added to the improved Unax Cooler, the lifespan has been dramatically increased. This is because numerous precautions have been set in place to avoid corrosion and general wear-and-tear, leading to a more durable product.
Higher efficiency 
The Unax Cooler has been designed to be able to handle a more diverse range of feed densities and temperatures. The system itself can be adjusted to suit your plant’s needs, making it more efficient than other coolers on the market.
Fewer spare parts
The limited number of lifter and wear plate designs enables using the same parts for different coolers. This eliminates the need to maintain an extensive and costly stock of replacement parts, allowing you to save more of your money. Also, the standardisation of cooler internals, which is a significant feature of the new design, allows us to maintain a sufficient stock of parts for swift delivery to your refinery.
Shorter installation time
The fitting of new internals is simple and straightforward, making the installation experience a lot quicker. The standard plates and lifters are easy to handle and lock into position, and compared with other designs, only a small number of bolts are needed, which also makes for a shorter installation time.

Features that increase lifespan and boost equipment reliability

The improved design of our Unax Coolers is a result of the numerous features that have been added, which have enhanced the durability, reliability, and functionality of the equipment overall.

Breaker lifters


Breaker lifters in the transition zone between the ceramic cam lining and the steel lifter zone reduce lump size in the cooler, which softens clinker impact on lifters and wear plates in the subsequent zones, reducing the risk of corrosion damage.


Improved lifter profile design


The edges of the lifters have been reinforced and the termination angle chosen lowers the effect of clinker impact, resulting in less wear-and-tear.


Improved cast wear plates


The wear plates overlap, protecting the cooler shell against excessive temperatures and wear. The loose wear plate design eliminates the risk of mechanical stresses, leading to more reliable equipment.


Dam rings


The dam rings in the cooler improve the retention time in the cooler and dramatically reduce the abrasion and impact on lifters and wear plates. Dam rings are flexible and can be placed in various places in the cooler to improve cooler efficiency, resulting in a more effective and durable product.


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