When a leading European plant manufacturer needed to investigate the economics of changing one of its key manufacturing processes it turned to TWI for help.
The Industrial Member specialises in making earth moving plant which are heavily reliant upon hydraulic rams, specifically the shiny actuators which operate the bucket and boom mechanisms. Presently they are chrome plated and then ground to precision dimensions. But could there be a cheaper surfacing process?
'It was an economic study' explains TWI's Dave Harvey. 'By performing an in-depth paper survey TWI investigated the economic arguments for and against changing from chrome plating to high velocity oxy-fuel spraying.'
The 25-50 micron coating is primarily for corrosion resistance. There have been some industrial developments, notably by leading competitors of this client, to develop an alternative alloy that meets the performance requirements, at a price that is competitive with hard chrome plating.
TWI took into consideration the costs of all the operational stages involved. 'In turning raw bar to a completed chromed actuator there are several operations; induction hardening, grinding, plating, finishing and polishing.' explains Harvey. 'It was our job to work out whether any different economically attractive steps could be taken if the client switched to HVOF coating'.
The client was already able to provide considerable data on chrome plating.
What TWI had to do was determine like-for-like operations and costs.
It found that many operations were actually really similar for both processes.
But the big difference lay in the price of the coating material.
As part of the work TWI calculated the required price of surfacing consumables at which using the HVOF process would become economically viable.
If you are an Industrial Member company and would like advice on surfacing processes, please contact us.