Siemens Industrial Turbines were struggling with the reliability and longevity of their transport cocoons made from ABS plastic. They tasked design company Assystem who subsequently contacted us at NORCO for a composite solution, which was accepted and the three parties collaborated together to develop a more robust alternative.
The pre-NORCO ABS plastic design was failing and could not withstand the rigours of airfreight. The new design brief enabled additional features and improvements to be incorporated. This called for tighter control over the internal and sealing surface with the base frame.
We manufactured a composite tool from a CNC pattern. The use of a male mould controls the internal geometry of the cocoon and guarantees high levels of repeatability. The cocoon shell is made from a lightweight construction of toughened epoxy prepreg glass with a PVC foam core. The double skin and closed cell foam core provides significant improvements in stiffness and damage tolerance.
Prior to delivery, the finished cocoon shell is dry fitted to a base frame. We also managed the supply of the base frame, which provides Siemens with a one-stop-shop solution for the complete transportation unit.
The cocoon shell is fully fitted out by our assembly team with lifting points, hatches, signs and a seal around the base. A dehumidifier unit is installed into each cocoon so they can double up as long term storage containers by Siemens customers.
A final test fit of the prototype cocoon with the gas turbine engine inside was carried out to check for any potential clashes. The finished cocoon also saw a 30% weight reduction vs the ABS plastic design as well as marked rigidity improvements when lifting and handling.