Pinions instead of belts

Gravel plant reduces costs and maintenance

2a and b: Bisher gab es im Werk von NorStone viele Grabungsbänder wie das in Bild 2a abgebildete, an dem Zapfwelle und Riemenantrieb mit zwei 55 kW-Motoren verbunden sind. An neu ausgestattete Bänder hingegen sind nun Kombinationen wie das in Bild 2b gezeigte Getriebe SK 9086.1 samt 90 kW-Motor angeschlossen ● The NorStone plant used to have many excavation belts such as the one shown at the Fig. 2a with shaft and drive belt connected to two 55-kW motors. By contrast, the refurbished belts are equipped with combinations, such as the one shown in Fig. 2b, of an SK 9086.1 gear unit and a 90-kW motor

3 Harte und vor allem reichlich staubige Bedingungen: Unter den Brechern auf Band 10 wird mit dem Getriebemotor SK 9052.1-160L/4 ein 15kW-Antrieb eingesetzt ● Harsh and dusty conditions: a 15-kW drive with an SK 9052.1-160L/4-type geared motor is fitted below the crushers on belt 10

4 Das Werk in Tau liegt unmittelbar an der See und hat einen eigenen Anleger, der jährlich von 700-900 Schiffen angelaufen wird. Am Ausfuhrband wird ein 37 kW-Motor mit dem Getriebetyp SK 9082.1-225S/4 eingesetzt ● The NorStone plant used to have many excavation belts such as the one shown at the left with shaft and drive belt connected to two 55-kW motors. By contrast, the refurbished belts are equipped with combinations, such as the one shown at the right, of an SK 9086.1 gear unit and a 90-kW motor

Summary

In many gravel pits, stone crushing plants and similar operations, conveyor belts are powered by shaft and belt drives. For a long time, this had also been the case at the gravel plant of NorStone AS in Tau, located in the southwest region of Norway (Fig. 1). However, recently NorStone, a subsidiary of the German HeidelbergCement AG, decided to change to robust geared motors. This option promised lower investment costs and increased operational reliability, along with better process safety. In addition to that, the operators anticipated an energy consumption reduction thanks to higher efficiency of the new drive systems.

1 The Norwegian producer NorStone

NorStone is Norway’s largest producer of gravel products. The company supplies aggregates for concrete and asphalt, stone cladding for coastal regions, and other special products. Each year, NorStone’s production facilities produce over 6.6 million tons of gravel products of various sorts and qualities. The demand is large, and even with its present annual production capacity of 2.3 million tons of material the Tau plant can scarcely meet the demand. It is therefore all the more important to ensure high availability of the plant and minimize unplanned downtime.