Conservative industries are generally characterized by very precise product requirements and very little or no room for either improvement or innovation. While this may be true, it has certainly not kept Westad from seeking more efficient and cost-effective ways to provide the services its customers demand. The latest innovation: Following an investment of slightly less than 1 million euros, Westad now relies on powerful laser beam welding technology in its manufacturing processes.
Just as there are valves for just about every application in the process industry, individual industries also feature highly specific valve types and characteristics. In this context, the maritime industry is no exception: The disks of LNG valves, for example, have to be coated with an additional layer – typically Stellite, a cobalt-based material – in order to ensure that the sealing surface cannot be scratched or develop other defects. In the past Westad outsourced this part of the production process, also known as "hard facing", to a subcontractor in Norway. "Contracting a third party to do this job cost a substantial amount of money every year," remembers Jørn-Inge Throndsen, Managing Director of Westad, and adds: "As a supplier of high-quality and critical valves, we came to the conclusion that it would make more sense to integrate this part of the manufacturing process into our core business in order to achieve optimal control in terms of both quality and output." What followed was extensive research on the side of Westad into alternative solutions.
After identifying, discussing and subsequently dismissing several proposals, the Norwegian colleagues finally "struck gold" in the Industry 4.0-related field of additive manufacturing, which relies on 3D design data to build up a component – layer by layer – by depositing material on another surface. In the case of Westad, the technique is called laser cladding or laser deposition: A stream of the desired (metallic) powder is fed into a focused laser beam as it scans across the target, the disk of the LNG valve. Upon cooling, it leaves behind a coating of the chosen material, i.e. the laser-precision applied layer, which will in future protect the valve from damage and thus potential leakages. At the same time, the new technology also offers both Westad and its customers a wide range of benefits: Compared to traditional electron beam welding, laser welding is achieved at twice the speed but with significantly less heat to the base material. This also ensures that the additive mixes less with the base material, resulting in a cleaner surface, which again means less final machining. And thanks to the underlying high-precision additive manufacturing algorithms, the process is also indefinitely repeatable and requires significantly less additive material to complete.
"We have been the proud owner of a fully automated welding laser beam cell since October 2016," explains a visibly proud Jørn-Inge, "it features its very own 6-axis ABB robot which enables us to treat even the most complex surface structures." And the company has every reason to be proud: The first LNG discs manufactured with the new technology were delivered less than half a year later in March 2017. And Statoil, Norway's main oil company, has in the meantime revised its general specifications for cladding/hard facing to include Westad's innovation. At present, Westad is the only company to currently meet the requirements of Statoil's TR2000 standard.
New business for Westad
"We are continuously adapting the laser welding technology to meet the very specific requirements of the marine industry," confirms Jørn-Inge, adding: "For example, we have recently partnered up with another company to create a new type of butterfly valve that will require laser welding. Furthermore, we are also looking at related industries, which work on the basis of similar principles: Take, for example, the subsea field where a technique comparable to cladding is used to protect piping and connector products against corrosion and erosion." However, the laser welding technology should not be exclusively limited to the marine industry and Westad is also looking beyond its own field of expertise: Surface-welding discs for metal-sealing double-offset valves, anti-corrosion treatment or wear coating inside of valve bodies are just a few of the likely scenarios that customers from related or other industries may find attractive.