Our customer designs and produces a range of Industrial Air Equipment systems used to provide breathing and ventilation application in hazardous environments so that work can be carried out safely.

The design of the bespoke Fan Assembly was designed to provide ventilation of train tunnels when excavation and maintenance work is being carried out. This fan design proved successful and out of that design concept other variants of the design were required.

The initial design was modular and allowed for a stackable system to be created. Other introductions included a bi directional louver to allow for better directional control and a range of impeller sizes to produce more air flow when required.

Our challenges were to take the initial design of the fan assembly, make it more portable, accommodate further new features and create a new design.

At over 2000 kg the unit was on the heavier side to be transported to and from various sites using their normal transport methods. We were therefore tasked with the challenge of reducing the weight of the unit and incorporating the new design features required.

The design issues that were required on this project needed resolving from a functional perspective. The hazardous environment, to which the centrifugal fan is to operate in, required that the frame assembly must be robust but lighter than the existing design. Suitable guarding was also needed around the equipment to ensure that it met with the machinery directives for safety of rotating equipment.

In our solution we changed the overall size and section modulus of the frame fabrication and completed an FEA (Finite Element Analysis) to ensure that the frame still met with the same operating specifications. Further changes to the shape of the frame, enabled more weight to be removed as well as making the design more flexible for its intended purpose. Other functionality changes included

– Allowing for different impeller sizes to be fitted to the frame
– Allowing for a removable ladder ease of maintenance and site installation
– A directional louver at the front to guide the flow of air horizontally or vertically.
– A turntable to the base of the design to allow for further directional ability.

The final design incorporated all the features requested and now contributes to creating a safer working environment for tunnelling engineers today.