High deposition rate laser cladding in hydraulic applications - HiDEPO

Project summary

Manufacturing and overhauling of hydraulic cylinders is increasing business in Europe. This is attributed primarily to the growth of renewable energy applications such as wind turbines and wave energy systems where the hydraulics play important role. Hydraulics are also widely employed in mining and construction, oil & gas drilling and other energy applications. Due to demanding operating conditions (wear, corrosion, static and dynamic loads), hydraulics is frequently surfaced with various wear and corrosion resistant coatings manufactured by hard chrome plating and thermal spraying to extend their service life and performance. Consequently, surface engineering is key technology in hydraulic cylinder manufacturing and overhauling as the failure of a cylinder renders likely the entire hydraulic-bearing machine inoperable which leads to high financial losses, pollutant emissions to environment and compromised human safety. Due to insufficient coating properties obtained by conventional surfacing techniques, several premature failures of key hydraulic components have been reported particularly in marine and offshore applications. For instance, in oil & gas drilling, piston rod failures of riser tensioning systems due to insufficient coating properties can lead to losses more than 550 000 USD per day. Piston rods composed of solid Ni-based super alloys and duplex stainless steels are good alternatives in many conditions but they are cost prohibitive. Laser cladding is promising new surfacing technique for hydraulic applications. This method combines the strength and availability of low cost steels with excellent corrosion resistance and good adhesion of metallic coatings based on fusion bond. Drawback of current laser cladding technologies based on coaxial powder feeding and 3-6 kW laser devices is, however, low cost-efficiency. The objective of this proposal is to develop novel high deposition rate laser cladding techniques, unique know-how associated with their optimum function and advanced coating solutions for surfacing large hydraulic components. This will allow for higher performance repairs and coatings with improved properties. Significant enhancements in deposition rates and cost-efficiency are achieved by utilizing the state-of-the-art high power diode lasers (HPDL) at the power range of 6-20 kW and developing novel hybrid cladding techniques based on preheated coaxial wire and strip feeding. By the development of innovative, environmentally-friendly and sustainable surfacing technologies, participating SMEs enlarge their business potential, access new markets and become more competitive in global market. By adopting new production methods, end-users reduce their maintenance costs, increase the efficiency of their processes and material efficiency by replacing solid high alloyed metal products with low-alloy steels surfaced with layer of high performance laser coatings. Environmental and safety impact will be enhanced by developing alternative coatings and manufacturing techniques to environmentally hazard hard chrome plating processes which are widely employed in hydraulic applications.