O&K is a German-based company known for the manufacture of railway equipment and vehicles as well as large hydraulic excavators. Founded by Benno Orenstein and Arthur Koppel in 1876, O&K began by developing a portable light rail system to move rock and soil more efficiently. To increase productivity O&K mounted backhoe excavators to the rail cars. These excavators eventually became freestanding machines powered by steam and then diesel, and traveled on crawler tracks.
O&K became the first European company to produce all-hydraulic excavators. It also led the way to introducing electronic control and monitoring systems.
 Entering the Portable Light Rail Market
At the Paris World Exposition of 1878, Arthur Koppel attended a presentation by Paul Decauville, a French railway pioneer. Decauville was showcasing a portable light rail system he believed would be ideal for the agricultural industry. His invention was awarded the gold medal at the 1878 Expo. Koppel believed this light rail system would be perfect for use in Eastern Europe and so he brought it back home with him to Germany.
Benno Orenstein and Arthur Koppel had been partners since 1876, and together they introduced the light rail system into new markets: Russia, Egypt, and South-West Africa. Initially O&K were reluctant to get into the manufacturing of locomotives, instead focusing solely on laying the rail tracks and purchasing locomotives from other distributors.
 Factory Openings
It wasn’t until 1890 that O&K developed its first locomotive factory, Maerkische Lokomotiv-Fabrik in Schlachtensee, Germany (near Berlin). In 1892, O&K printed a catalog, which included discussions of light railway problems. The catalog, which was entitled Leichte Lokomotiven (“Light Locomotives”), included no engines manufactured by O&K because none had been produced yet. Also, instead of distributing the book to potential customers, it was only available for purchase from bookstores.
In 1893, O&K constructed a light railway equipment factory in Dortsfield. When the company became more serious about locomotive manufacturing, it purchased a new factory in Drewitz, combining it with the Schlachtensee facility. The new 13,000 square foot (1,170 m2). facility was designed to manufacture 300 locomotives per year. However, the Drewitz facility only produced 100 locomotives its first year, 200 in its second year, and fluctuated the following years until it reached its potential in 1905. From then on, the factory excelled in production, and by 1908 it was producing 600 locomotives per year.
 Product Developments
With the success of O&K light rail systems came new innovations creating new forums for income. In 1908 it produced its first backhoe excavator, initially mounted to the rails. By 1922, these excavators were steam-driven and moved on crawler tracks. In 1926 diesel engines replaced steam engines. Then, in 1934, O&K introduced the first bucket wheel excavator.
After 1949, O&K seemed content to focus most of its energy into the development of construction and mining equipment, especially the manufacturing of excavators. By 1961 O&K was the first European company to produce all-hydraulic excavators. From then on, O&K concentrated all its efforts into being the forerunner in excavator development, leading to the introduction of electronic control and monitoring systems.
O&K eventually developed the world’s largest excavator: the 1000-ton RH400. The machine is so huge it can include a small kitchen and living quarters to adjoin the operating cabs.
In April 1998, O&K was acquired by the Terex Group for US$168.5 million. As a leader in the manufacturing of articulated and rigid trucks, coal trucks, scrapers, and hydraulic excavators, Terex, along with O&K, hopes to build powerful and cost-efficient mining equipment.
 The Company Today
As a part of the Terex Group, O&K continues to produce a number of different excavators of varying powers and sizes. It currently has sales sites around the world, with head offices located in Dortmund, Germany. Terex head offices are located in Westport, Connecticut, USA.
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