Dec 18, 2023
A modern autoclave process involves challenging conditions, and the autoclave must remain at the correct stream and pressure. Valves are a small but important part of the complex process: They control the flow and keep the autoclave’s process stable, helping ensure that the process vessel operates efficiently. This is why Neles™ and Jamesbury™ valves were chosen for MK Technology GmbH’s production unit in Grafschaft, Germany.
MK Technology has developed and produced specialist machines for vacuum and metal casting and testing in the field of rapid prototyping and production since 1997. Their fully automatic steam autoclaves are manufactured in their modern production facility near Bonn, Germany. The innovative products are exported all over the world. The modern high-tech company has close to 30 employees, and they have enjoyed successful cooperation with Valmet now for two years.
MK Technology’s unique production process is quite complex. The autoclave used in investment casting consists of two boilers. “In the first boiler, steam is generated from water. That is why we also call it a steam generator. In the second boiler – the actual autoclave – in which the wax-filled ceramic shells are located, the steam is abruptly injected at 192 °C and 12 bar,” explains Marius Kahl from MK Technology. The energetic steam melts the wax, beginning on its surface. Before the wax starts to expand, the surface has already liquefied completely and drained off. This way, destructive internal pressure does not build up at all. “Although this basic principle is very simple, its implementation is quite complex,” Marius Kahl continues.
Previously, the steam generator and the autoclave were located separately, being only connected by steam piping. Now the modern autoclaves are interlaced. “The advantage is that the steam generator, which is located around the autoclave, preheats it ‘virtually for free’ and thus saves a lot of energy,” states Marius Kahl. A multistage water processing, intuitive operations and numerous safety regulations of the admission board make the double boiler quite a complex system.
Valves are needed to control the flow, in this case the steam, and to keep the process running. There is a total of 14 control, on/off and manual valves installed in the autoclave process. The valves are used to control the steam injection, water condensate, wax and atmospheric balance outlet.
MK Technology has invested significantly in research to create an energy-efficient tool that guarantees a smooth dewaxing of the ceramic shell that is easy and safe to use and maintain. They therefore also needed safe, reliable, and efficient valves. MK Technology had experienced challenges with their existing on/off valves, as they were unable to keep up and lacked the desired pace and pressure to control the process sufficiently. In the long run, this could have resulted in delivery delays and lost business. A longer lifetime for the valves was therefore needed, and a quicker steam pressure inlet to 10 bar. So, MK Technology turned to Valmet’s flow control experts to look for an optimal valve solution for their needs.
MK Technology's expert checking the control valves
After thorough discussions and comparisons, MK Technology chose to go for Valmet’s Neles™ and Jamesbury™ control valves. “The use of a pressure control valve instead of an on/off valve has a smother pressure curve. The faster and more accurate control also secures our competitive edge,” says Mr. Kahl. “The good control performance and quick reaction time of our products helped achieve good controllability and a smooth pressure curve,” adds Marco Laudenbach from Valmet. Valmet’s scope of the delivery consisted of Neles and Jamesbury ball valves and butterfly valves for manual, on/off and control applications with Neles™ ND9000 intelligent valve controllers. “In future, we’re going to use the Neles NDX™ valve controller with digital outputs,” confirms Marco Laudenbach.
“We are very happy with the valve solutions Valmet’s flow control experts provided us. They work super well,” says Marius Kahl from MK Technology. “The control of steam transfer is according to our client’s requirements and expectations, and the transfer of the steam is now faster.”
The cooperation between MK Technology and Valmet was open and active. “Valmet experts are very competent and are committed to customer service. Thanks to Valmet’s deep industry knowledge, we can be sure they always offer the best possible valves for our specific needs,” concludes Mr. Kahl. He also added, “MK was more than enthusiastic about the fast and close cooperation and the optimizations, especially with Mr. Laudenbach.” “Valmet is happy to bring MK Technologies’ products and solutions to a higher level and really appreciated the open-minded cooperation and development,” says a smiling Marco Laudenbach.
Neles and Jamesbury control valves on top of the autoclave