Butterfly Dampers

Text Sepi Roshan
Photos Tero Takalo-Eskola

Sammet’s Product Group Manager Mr Jyrki Kuitunen is brimming with enthusiasm as he prepares to discuss the products he helps design and manufacture. Louver and butterfly dampers are Sammet’s most popular product groups, and commonly used in powerplants and by processing industries.

Mr Jyrki Kuitunen, Product Group Manager at Sammet.

Kuitunen’s relationship with Sammet started during his engineering degree when he researched Sammet’s damper control systems for his thesis. The work was of such high quality, Kuitunen was offered a full-time position with Sammet. That was 20 years ago.

Just like Kuitunen, Sammet’s louver and butterfly dampers are a reliable and indispensable part of Sammet’s business. Kuitunen clearly enjoys his work and sharing his knowledge.

Tried and true products

He starts with the basics, explaining that a louver damper is rectangular in shape and a butterfly damper is round, but that the operating principles and mechanical properties are similar. The louver and butterfly dampers can have two functions: On/off (i.e. isolating) or control (i.e. regulating) gas and air flow. They are the most popular and established product groups, commonly used in powerplants and processing industries.

While the on/off damper blades sit parallel to each other, control damper blades turn towards each other and the flow is directed to the centre of the duct for better control. “The blades in the round control damper look like butterfly wings as they move around the central access, which is where the name comes from”, Kuitunen says with a smile. Butterfly dampers are used where flow control and low leakage isolation are a priority. These dampers are especially useful in applications such as Sammet’s world class designs for scrubber systems. A Finnish beer factory is one of the more interesting places to benefit from these Sammet dampers.

Meeting the diverse needs of customers worldwide

Any engineering parameters, such as materials and design, painting and project documentation can be tailored to specific customer needs. Damper sizes range from the smallest DN60 flap damper to an 8x8 meter on/off damper. Maximum tightness is 100% and the minimum tightness is always specified by the customer. Flow speed in ducts is typically between 15 to 25 m/s to prevent too much high-pressure loss. Other important specifications that can be tailored to customer needs include dimensions, pressure, temperature, actuator and accessories, surface treatment and materials. Some purifying plants have very abrasive particles in gas flow and Sammet uses special steels to manufacture the dampers to prevent unwanted wear and tear.

Jyrki Kuitunen, Sammet Louver Dampers

"We are always here to provide what the customer wants”, declares Jyrki Kuitunen

The Sammet team is always able to cater for customer specifications. For instance, dampers can be connected to ductworks by flanges or welding.  “Some customers need to easily remove dampers for servicing and they require flanges to connect dampers. Other customers prefer welding because some dampers, such as those produced by Sammet, do not need heavy servicing that requires removal. We are always here to provide what the customer wants”, declares Kuitunen. Sammet also supports customers with after sale services ranging from spare parts to comprehensive, onsite damper servicing.

"Sammet is like the Mercedes of the damper world - and we invite you all to come for a ride."

Sammet employs strict quality control when sourcing materials. “According to our quality plan, all materials must be sourced with material certificates and in China our manufacturing facility also undertakes material chemical analysis tests to verify material content and quality”, explains Kuitunen. In addition, with manufacturing facilities in Europe (Estonia, Poland, Finland) and in Shanghai, China, Sammet can deliver dampers to any destination worldwide. “Depending on manufacturing capacity and customer specifications, our delivery times range from 6 to 18 weeks”, says Kuitunen.

Customers appreciate Sammet’s reliability and quality

Sammet has delivered over 20,000 louver and butterfly dampers to customers across the globe. These customers are telling Sammet they appreciate the reliability and long operating life of these dampers. Finnish components and products are renowned for their high quality. The Sammet team’s expertise is matched by an openness and ease of communication with customers throughout the project process.

Finding optimal solutions for customers is a passion for Sammet. Finnish people are characterised by a concept called “sisu”, meaning they do not give up easily when problems arise. Sammet’s customers can always rely on Finnish commitment to find solutions. Kuitunen recalls a recent technical challenge where there was very limited space to fit a damper and its accessories. Together, the Sammet team and the customer identified a bespoke solution to the layout challenges, resulting in a perfect fit for the damper and actuator.

Kuitunen finishes by summing up Sammet’s louver and butterfly dampers with two words: Reliability and quality. “They are like the Mercedes of the damper world”, he says, “And we invite you all to come for a ride”.

For more information about Sammet's innovative louver damper technology, continue to read Spotlight on Sammet Louver Dampers for industry