Olsberg GmbH

About Olsberg

Olsberg GmbH is a family-owned company headquartered in Olsberg in the Sauerland region, tracing its origins to the Olsberger Hütte, first documented in 1495. The company is organized into three business units: The Casting Technology unit produces highly precise, complex and thin-walled castings from cast iron, made among other things for the heating appliance industry and general mechanical engineering. The Sheet Metal Technology unit processes steel, stainless steel, aluminium and copper into precise sheet metal components, primarily enclosures for external business partners from the electronics and construction sectors. The Heating Technology unit develops and produces design-oriented wood-burning and pellet stoves. All three business units as well as company management are located at the headquarters in Olsberg; serial castings receive their surface finishing in Brilon, and the foundry of the subsidiary Olsberg Königshütte GmbH & Co KG in the Upper Harz supplements the casting capacity. The company employs around 260 staff and is certified to DIN EN ISO 9001:2015, ISO 14001 and ISO 50001.

Site

Olsberg

Processes

Casting Technology – production of highly precise cast components (complex, thin-walled castings), Surface finishing for serial castings, Partial and final machining of castings, Sheet Metal Technology – processing of thin sheet material, production of precise sheet metal, Manufacture of wood-burning and pellet stoves, Casting Technology: highly precise, complex, thin-walled castings, Heating Technology: wood-burning and pellet stoves, Sheet Metal Technology: enclosures and sheet metal components (steel, stainless steel, aluminium,

Materials

Cast iron, Iron casting / cast iron products, Steel, Stainless steel, Aluminium, Copper, Cast iron (iron casting)

Certificates

DIN EN ISO 9001:2015, DIN EN ISO 9001:2015 (Brilon site), DIN EN ISO 50001:2018 (Energy management, Olsberg site), DIN EN ISO 50001:2018 (Energy management, Brilon site), DIN EN ISO 14001:2015 (Environmental management, Olsberg site), DIN EN ISO 14001:2015 (Environmental management, Brilon site), AD 2000 Merkblatt W 0 (Materials manufacturer), EcoVadis Silver (Rating 2025/2026, 75 points), BSFZ seal (Research and Development), ISO 9001, ISO 14001, ISO 50001, AD 2000 Merkblatt W 0, EcoVadis Silver

Founded

1495

Employees

260

Industries

Heating appliance industry, General mechanical engineering, Electronics, Construction

1. 01

   Development and design (research and development, BSFZ seal)

2. 02

   Foundry (Casting Technology, among others in Königshütte)

3. 03

   Automated casting finishing (fettling machine Reichmann MAUS 900 TL)

4. 04

   Partial and final machining of castings

5. 05

   Surface finishing of serial castings (Brilon)

6. 06

   Sheet metal processing (enclosures and sheet metal components)

7. 07

   Assembly (wood-burning and pellet stoves)

8. 08

   Shipping to industrial customers

Materials and Processes

Locations

Olsberg

DE

Headquarters: all three business units (Casting Technology, Heating Technology, Sheet Metal Technology) and company

Materials

Cast iron, steel, stainless steel, aluminium, copper

• Fettling machine Reichmann MAUS 900 TL (automated casting finishing)

Brilon

DE

Surface finishing of serial castings and shipping to industrial customers

Materials

Cast iron

Königshütte (Upper Harz)

DE

Foundry of the subsidiary Olsberg Königshütte GmbH & Co KG; castings for the heating appliance industry and mechanical

Materials

Cast iron

Components and Products

Inside the production

Processes & technical limits

1 Anlagen & Maschinen

Quality and Certifications

Olsberg GmbH operates certified management systems according to DIN EN ISO 9001:2015 (TÜV NORD), ISO 14001 and ISO 50001 and is recognized as a materials manufacturer under AD 2000 Merkblatt W 0. Its sustainability performance was rated Silver (75 points) in the 2025/2026 EcoVadis rating.

History

1. 1495

   First documented mention of the Olsberger Hütte (deed of the Imperial Chamber Court regarding the sale of three shares, Westphalian State Archive Münster).

2. 1577

   Construction of a water channel to the Gierskoppbach at today's headquarters; start of ore smelting (from dispute file of 1584).

3. 1597

   Gerd Krüper and Heinrich Stengel mentioned as owners in the inventory book of the Duchy of Westphalia.

4. 19. Jahrhund

   Transition from ore smelting to casting technology with the first cupola furnace; Olsberger Hütte becomes a significant manufacturer of cast iron products; start of stove manufacturing (Halbmond wood-burning stove 1860).

5. 20. Jahrhund

   Expansion of Heating Technology (cooking stoves, cooking appliances, oil stoves, electric storage heaters, heat pumps) and introduction of Sheet Metal Technology.

6. 1965

   Edward Kersting joins the Olsberger Hütte on 01.10.1965 and takes over as managing partner; start of series production of electric storage heaters.

7. 2000

   Ralf Kersting takes over as managing partner on 01.04.2000; start of export orientation.

8. 2017

   Discontinuation of the thermal storage business and sale of the Japanese subsidiary; Ralf Kersting ends his operational activities on 31.12.2017.

9. 2018

   As of 01.01.2018, Ulrich Herrmann and Stefan Osebold become managing directors.

10. 2024

    EcoVadis certification (Bronze, 59 points); company visit by Friedrich Merz, Member of the German Bundestag.

11. 2025

    Upgrade in the EcoVadis rating from Bronze to Silver (75 points, top 6% of industry and size class).

12. 2026

    Commissioning of the automatic fettling machine Reichmann MAUS 900 TL; another EcoVadis Silver medal; recertification to ISO 9001 by TÜV NORD.