News –

NORD drives ensure trenchless tunnel construction in Abu Dhabi

Underground project of the century: A new sewage tunnel is under construction in the capital of the United Arab Emirates. Drive solutions from NORD ensure safe transport of personnel and materials with lifting equipment in the access shafts.

Bargteheide, 2019-04-19

40 kilometres, up to five metres diameter, 800,000 m3 waste water: The new sewer construction in Abu Dhabi is gigantic. The "Strategic Tunnel Enhancement Programme" (STEP) is intended to meet the increasing demand for sewage disposal. In order not to inconvenience the inhabitants and public life in the metropolis more than absolutely necessary, the tunnel construction had to be carried out without trenches and from tunnel shafts. Lifting equipment with robust drive solutions were required, which could operate almost without maintenance for more than two years and were capable of operating as synchronous pairs in order to lower personnel and materials over considerable distances of up to 90 metres.

The conveyor technology specialist ElectroMech from India utilised NORD expertise for this mammoth task. Over the years, the two partners have implemented several projects. This time solutions based on heavy duty bevel geared motors were jointly developed for the main and auxiliary lifting equipment, which have an efficiency of more than 95% and also a very high load capacity. Each crane was equipped with a pair of drums with two separate drive systems, each consisting of a geared motor and frequency inverter.

Automation of the entire system utilises encoder signals to perfectly synchronise the two drums, so that there is no risk that the supply platform will become dangerously tilted. NORD inverters with field-oriented control work to ensure constant speeds and high starting torques even with varying loads. With this, loads can be precisely, quickly and carefully positioned.