Advanced remanufacturing boosts compressor repair innovation at Howden
Background
Howden, a Chart Industries Company, is a global provider of mission-critical air and gas handling products for a range of industries. It partnered with the National Manufacturing Institute Scotland (NMIS) to explore more sustainable ways to extend the life of screw rotors, which are vital parts in industrial compressors.
Worn rotors are typically replaced, with lead times of up to several months. These parts are also chrome-plated using a 100-year-old process involving chromium trioxide - now heavily restricted under European Union Registration, Evaluation, Authorisation and Restriction of Chemicals (REACH) regulations. The project set out to modernise this process with cleaner, faster repair methods.
What did NMIS do?
Through the ReMake Glasgow project, funded by the Glasgow City Region Innovation Accelerator programme, NMIS trialled advanced techniques, including laser directed energy deposition (DED), high-velocity oxygen fuel coating, and cold spray manufacturing. Cold spray was selected as the most effective by depositing material without heat and avoiding distortion.
NMIS researchers developed a novel coating with nine times better wear resistance and four times improved fatigue performance than traditional chrome plating. The team also supported lifecycle assessment (LCA), cost modelling, and the integration of a Digital Product Passport (DPP) to capture detailed information including materials, processes, and lifecycle data, enabling efficient remanufacturing and potentially creating new revenue streams through servitised business models.
Training was delivered through the NMIS Manufacturing Skills Academy to build in-house circular manufacturing expertise.
Impact
The project helped demonstrate the technical and commercial feasibility of cold spray remanufacture, supporting Howden to explore future in-house capability. If applied at scale, each remanufactured rotor could save up to 40 tonnes of CO₂, equivalent to the annual emissions of 29 average UK cars, with significant potential across Howden’s global installed base of more than 40,000 compressors.
It also provided a blueprint for potential new aftermarket models — where components are returned, refurbished, and redeployed — helping to extend product life, retain value, and reduce environmental impact.
.png)
Fraser Jardine, Lead Product Engineer at Howden, said:
This project helped us develop a model to extend the lifespan of our compressors and explore new ways to repair parts instead of replacing them. With NMIS’s support, we now have the evidence and confidence to invest in more sustainable processes, keeping value and skills local and reducing our environmental impact.