Kolster Engineering and Hesa-tek were merged in 2008 to form Kolster Hesa-tek. The joining together of the two companies means that we can supply an even better service to our customers in the energy sector.

Our product range is designed to meet the diverse requirements of modern enterprises and high-tech processing plants in many areas. Kolster Hesa-tek is now a leading producer of both dampers and heat exchangers.

Dampers for the power generation industry

We supply a range of damper products to the power generation industry, including flue gas dampers, butterfly dampers, louver dampers and guillotine dampers.

The dampers are typically produced in consultation with the client to ensure the best result. For this we use our know-how built up over many years and combine it with new knowledge and techniques to achieve the best solution.

Our DSVK butterfly dampers are high-quality, low-cost and extremely reliable.
LDS louver dampers are typically designed especially for specific requirements in terms of temperature, pressure and materials.
Our AS guillotine dampers are used mostly as shut-off valves.
Our tube heat exchangers are produced in a wide range of materials and sizes, specifically designed according to requirements.
All work is done according to the present rules and regulations for the specific field.

Butterfly dampers

Our DSVK series of butterfly dampers is based on many years of experience with flue gas dampers. Our DSVK butterfly dampers are high-quality, low-cost and extremely reliable.

Sizes range from DN 200 to DN 1000 for circular dampers, and for square and rectangular dampers from 200mm x 200mm to 1,200mm x 1,200mm with 50mm intervals in the shaft direction and/or height.

The dampers are designed by means of a 3D computer-based analysis program, based on a temperature of 300°C and pressure difference of 5,000 Pa. The damper frame construction is based on a standard steel profile or a welded frame. The result is a strong, solid construction in any running condition. Frame and flanges remain stable and in shape even at high temperature and pressure conditions.

To achieve excellent flexibility the DSVK butterfly damper series is modular, so from the basic version dampers can be built which exactly meet customer requirements.

The ‘big brother’ butterfly series type DS is where the damper plate has an airfoil shape, which provides great strength and minimum pressure drop. The ‘all-way-through’ shaft is mounted in heat-resistant bearings, which ensures a solid, strong and reliable unit.

The DS damper is typically designed to meet the customer’s exact requirements. We have delivered hundreds of type DS dampers from DN 1100 to DN 3600 for Aalborg Industries to shipyards in Korea and other locations around the globe.

Louver dampers

Our LDS louver dampers are mainly used for regulation purposes and as shut-off valves where there is a lack of space for the damper plate. The shaft and bearing design can be constructed like our DS type dampers, or as a combined bearing and shaft seal with axle pins. LDS louver dampers are typically designed especially for specific requirements in terms of temperature, pressure and materials.

Guillotine dampers

Our AS guillotine dampers are used mostly as shut-off valves. The damper plate rests on self-cleaning sliding pivots and is close to the sealing bar above. AS type guillotine dampers can be supplied with or without a cover plate. AS guillotine dampers are typically specially designed for our clients’ specific temperature, pressure and material needs.

Tube heat exchangers

Our tube heat exchangers are used in a wide range of applications; for example, for the hot water supply of central water warming by steam, hot water, district heating or HT-oils. Especially in connection with steam applications tube heat exchangers are very often superior to plate heat exchangers, due to their robust design, much higher life expectancy and lower maintenance costs.

In addition, tube heat exchangers are used in a wide range of industrial applications as well as on power plants, etc. and are produced in a wide range of materials and sizes, specifically designed according to requirements.

Our market is mainly production, repair and design of tube as well as plate heat exchangers and other kinds of pressure vessels. HESA-TEK also undertakes the extension / drawing and retubing of tube heat exchangers, as well as the manufacture or repair of vessels, condensers, evaporators and similar products.

Our well-equipped service car can be seen all around the country, and we take on a very wide range of jobs all around the clock, all year round.

Rules and regulations

We work according to the rules and codes present for this specific field. For welding that means using approved welders according to EN287/PED and approved welding procedures according to EN288-3/PED or ASTM IX. In terms of mechanical design we work according to the different codes governing this field, such as EN13445, AD-Merkblätter, BS 5500, ASME VIII, TBK/NORSOK, and Lloyd’s and DNV’s rules and regulations. We work with a wide range of materials.

Materials for heat exchangers

We use the following materials in the manufacture of our heat exchangers:

  • Pipes, plates and forged in carbon steel according to US standard ASTM and European standard EN 10028-2, -3
  • Pipes, plates and forged in austenitic-ferritic stainless acid-resistant steel according to ASTM (AISI 304/316) and European standard EN 10028-7
  • Aluminium brass, seawater-resistant brass and titanium

All materials can be delivered fully documented in accordance with EN 10204 3.1 or 3.2 licence.