Continuous and Lasting Performance

1 | 4  About Wey

With a patent registered in 1956, we revolutionized the design of knife gate valves forever. The engineer’s name: Joseph Wey. The Original Wey Design and the Wey brand were born.


A Swiss innovation conquers the world

Wey products and solutions have been conquering the world ever since, and today stand for performance, reliability, quality and cost-effective solutions for knife gate and butterfly valves as well as water control gates.

Any application, anywhere in the world

Whether in mining, the pulp & paper or the food & beverage industries. Whether in wastewater treatment, oil & gas or chemical processing. Wey is the trusted name in the most demanding industries, all over the world.

There’s only one original

Often copied, but never equaled – ever since Joseph Wey’s invention and the launch of the Wey brand, Sistag has been setting standards worldwide.

Learn more about our company and our employees.

2 | 4 Values

Values that we live by and in which we believe

Reliability – our commitment
Our customers and partners can rely not only on Wey products, but also on the people behind them. Because delivering on our commitments is part of our DNA.

Quality – our attitude
At Sistag, quality is the keystone of everything we do. From the way we design Wey products, to the precision in execution, to installation and customer service.

Long-term cost efficiency – our perspective
Wey’s solutions are designed to meet not only technical specifications, but also economic requirements. This is why Wey solutions are among the most efficient when it comes to TCO.

wey valve

Facts & Figures

>1 Mio

Wey valves ensure reliable connections in many countries around the world.


Even with our largest current Wey knife gate valve, we pay attention to every detail.


distribution partners worldwide are here to help.


We exceed expectations and take every challenge as a personal incentive.

4 | 4 Certification

For us, quality is key

in order to develop solutions that meet the highest demands thanks to their precision and durability. This means we are also audited by external organizations.

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