From Eight Months to Nine Weeks: KSB Accelerates Impeller Production with Additive Manufacturing
Using the EOS M 400-4, KSB produced and delivered 14 Alloy 625 impeller blanks in nine weeks, supported by DNV-qualified additive manufacturing processes.
More Than 20 Years of Additive Manufacturing Experience
KSB is one of the world’s leading manufacturers of pumps and valves, operating in more than 150 countries. With over 20 years of experience in Additive Manufacturing, the company opened its Additive Manufacturing Center in Pegnitz, Germany, in 2018 to make this expertise available to other companies. The center covers the process chain from material selection and design to qualified component production. Through its Parts on Demand service, KSB also produces custom parts, prototypes, small series and impeller spare parts according to customer requirements. This approach enables components to be manufactured when needed, helping customers shorten delivery times and reduce the need to maintain extensive physical spare-parts inventories.
KSB’s experience extends beyond production. The company was the first manufacturer to receive TÜV certification for the Additive Manufacturing of components subject to the European Pressure Equipment Directive. Its AM facilities have also received a DNV Facility Qualification Certificate. For the impeller parts family, KSB holds a Qualification of Manufacturer according to DNV-SE-0568 and DNV-ST-B203 at AMC 3 level.
Challenge
During the overhaul of two multistage high-pressure ring-section pumps, KSB needed to supply 14 impellers for a demanding oil and gas application involving seawater exposure. The impellers therefore had to combine reliable mechanical performance with high resistance to corrosion. These parts were initially requested through the conventional casting route. However, the expected lead time for this approach was between six and eight months. For the operator, this timeframe was too long.
The challenge was not simply to manufacture the required geometry faster. The material and production process also had to meet the requirements of a demanding industrial application. KSB therefore needed a solution that could provide the required impellers within a substantially shorter timeframe while maintaining process reliability and the necessary level of qualification.
Industrial 3D printing offered an alternative to waiting several months for cast components. Unlike conventional production methods, it also allowed KSB to manufacture the impeller blanks directly from digital production data, using an internally qualified system and process.
Solution
KSB produced 14 impeller blanks on a qualified EOS M 400-4. The system enabled KSB to manufacture the large metal components within the required timeframe and according to its established AM processes.
Each impeller had a diameter of 409 mm. The build time for a single component was approximately 76 hours. For the material, KSB selected Alloy 625, a seawater-resistant nickel-based alloy suited to applications in corrosive operating environments. For this application, KSB obtained a DNV Facility Qualification Certificate at AMC 3 level for Alloy 625. The impeller parts family is covered by KSB’s Qualification of Manufacturer according to DNV-SE-0568 and DNV-ST-B203 at AMC 3 level.
The qualification process included fatigue testing of additively manufactured Alloy 625 against cast duplex steel. The results indicated improved fatigue performance compared with the cast material. In addition, Alloy 625 offered improved corrosion resistance, mechanical properties and geometric accuracy compared with the previous cast solution.
Resistance to seawater corrosion was particularly important. In oil and gas applications involving seawater exposure, corrosion can affect component durability and ultimately the availability of the surrounding equipment. The selected material and qualified additive manufacturing process therefore addressed both the immediate need for shorter lead times and the longer-term requirements of the application.
EOS’s Smart Fusion was used as part of the production approach. The technology supported process stability by helping to reduce deformation and the need for support structures during production. Its role was integrated into KSB’s overall manufacturing process, with the EOS M 400-4 remaining the central production platform for the impeller blanks.
"For me, the EOS M 400-4 stands out because its high process quality and the excellent synergy between material and process significantly simplify the certification process while ensuring reliable results."
Stephan Braun, Business Development Additive Manufacturing - Parts On Demand, KSB
Results
KSB produced and delivered all 14 impeller blanks within nine weeks, reducing the expected lead time of six to eight months for conventional casting. This allowed the customer’s pump overhaul to proceed without waiting several additional months for cast components.
The finished order demonstrated that KSB could translate its extensive AM experience into a qualified response to an urgent spare-part requirement. The Alloy 625 impellers provided the corrosion resistance required for an oil and gas application involving seawater exposure, while the EOS M 400-4 enabled KSB to manufacture components with a diameter of 409 mm within the required timeframe. Just as importantly, the project did not remain a one-off solution. The successful delivery met the customer’s requirements and resulted in a follow-up order.
By combining KSB’s application and process expertise with the production capabilities of the EOS M 400-4, the project shows how 3D printing for energy applications can provide a qualified production route for critical spare parts when conventional manufacturing lead times are too long.
