Industrial Gear Units and Services for Heavy Duty Applications

? The SEW-Unit Heavy Industrial Solutions has been introduced to the market in October 2012. What is the idea behind this positioning?

Holz: Heavy Industrial Solutions is not only about single large-scale gear units, but system solutions as well. And the demand for such system solutions is continuously increasing – currently mainly on the European market. But we see that this trend is also growing on overseas. This, too, was reason for us to ensure an optimal positioning in good time.

? What are the advantages of such system solutions?

Holz: System solutions offer a significant increase in efficiency along the supply chain. A typical industrial gear unit drive package consist of of a number of different components. In addition to the gear unit – if requested by the customer – we also deliver the brake system, coupling, motor, frequency converter, and control system. This allows for an optimisation of the interfaces between those components which results in a significant reduction of cost and complexity. With a solution that is optimally adapted to a certain application it is, in general, possible to achieve a higher efficiency, reduced space requirement and, quite often, a lower system weight.

? Where do you see the biggest demand for Heavy Industry Solutions and the respective system solutions?

Holz: Typical areas are, for example, material handling applications, mining, mineral processing, or sugar production. This is a fundamentally complex field – and this is also the challenge. To meet the specific requirements of a customer, commonly a solution specific for the respective application is required. We are increasingly covering these requirements by means of modular packages standardised towards a specific application. A good example for this is our programme of bucket elevator- and belt conveyor drive systems. Based on our global market strategy, we decided to serve certain priority branches and applications. Bucket elevators and belt conveyors are part of this programme, as well as e.g. hoisting, mixing and mill drives.

Mining company Store Norske is operating a open pit coal mine on Spitzbergen, a group of islands in the North Atlantic above the polar circle, a place where the mean average temperature is a low as -4.4°C. Part of the bulk material handling equipment at the mine is scraper conveyor manufactured by Halbach & Braun which receives coal from truck coming out of the mines and moves it to a downstream belt conveyor. The scraper conveyor draws the coal from a bunker which contains up to 120 t of material. “To draw the coal from the bunker with such heavy loads, a great power is needed”, explains Dr. Dietrich Braun, director and shareholder of Halbach & Braun. "Accordingly, the conveyor requires a drive system with a high gear reduction to create the necessary torque.” In case of the bespoke scraper for conveyor this means an operating torque of 29.4 kNm and a nominal torque of 130 kNm. However, despite the large torque, only a comparatively small motor power is needed because of the low conveying speed. This combination of high torque and small motor power call for a custom drive solution. “In such cases we generally use a drive system by SEW Eurodrive,” says Dr. Braun. “Because SEW has a large portfolio of standard components from which an suitable, individual drive solution can be compiled very fast. Because the components are are manufactured in large quantities, the systems have an attractive price, despite the customisation.” The solution selected for the scraper conveyor on Spitzbergen consists of a double drive system with 37 kW AC motor from the DRE type series and a 4-stage gear unit from the X type series of size 190. The motors are connected to the gear unit via a motor lantern and an elastic coupling. To make sure that the oil in the gear unit has the right viscosity even at the very low temperatures occurring on Spitzbergen, the system is also equipped with an electrical heating system. In case of a failure of the drive system, Halbach & Braun can resort to the world wide service network of SEW Eurodrive, which also has offices in Norway and Finland. However, Dr. Braun is confident, that this won't be necessary. “Because we have discussed the operating conditions with SEW Eurodrive at the beginning of the project, we do not expect to experience any unpleasant surprises.”