Laser DED additive manufacturing: Pelton turbine bucket (energy / hydropower)

Manufacturing Pelton runners requires the production of buckets with complex geometries, subjected to extreme conditions of cavitation, erosion and corrosion. The challenge is to reduce material losses and assembly constraints while improving production flexibility and lead times.

IREPA LASER has developed a solution for manufacturing buckets using wire-fed laser DED on a forged base. The approach is based on a complete digital chain integrating 3D reverse engineering, toolpath generation and thermomechanical simulation to secure manufacturing.

Manufacturing the bucket requires simultaneous control of process stability and thermomechanical phenomena on a complex geometry. The key challenge lies in maintaining consistent metallurgical quality while managing high deposition rates, without compromising the precision or integrity of the part. In addition, high performance must be guaranteed in a harsh environment (cavitation, abrasion, corrosion), while ensuring the industrial reproducibility of the process on large parts.

The demonstrator produced a 61 kg functional part at a high deposition rate (6 kg/h). The solution guarantees a dense part that meets mechanical requirements, validating a hybrid approach combining manufacturing, repair and the optimisation of costs and lead times.