Crescent Tower: Elevator Modernization

The modernization of this tower included an update of its elevator system to increase reliability, safety and improve traffic performance.

by Thorsten Elsaesser

The 22-story Crescent Tower is located on the corniche (a road on the side of a cliff or mountain) of Sharjah, a prime location in the U.A.E. Built in 1996, the tower is owned by Emirate-NBD, a large banking group in the Middle East, and houses oil and gas company offices. Prior to the modernization of the building’s elevators, tenants experienced long waits during peak travel times. In addition, the elevators did not conform to the latest safety standards. A prerequisite to the modernization was to increase reliability and safety of the elevators, and improve traffic performance. 

The project started in October 2009 and was completed in April 2010. One of the main obstacles ThyssenKrupp Elevator (U.A.E.) faced during the modernization was in the building structure itself. The company modernized four elevators capable of speeds up to 3 mps: three 1150 kg passenger elevators and one 1600 kg service elevator. However, the machines and machine frames could not be transported through the narrow staircases in the building, and therefore, required a crane to hoist the equipment to a height of 100 m to the top of the building. In addition, the machine room had no opening to bring the machines inside, requiring a 2- by 3-m opening to be cut to reinforce 300 mm of concrete. During the modernization the building was fully occupied, and work had to be done during late afternoon and night shifts. 

Elevator Features and Specifications

ThyssenKrupp installed its destination selection control (DSC Booster) to the ground floor and mezzanine floor elevators, with conventional push buttons at all other landings. The DSC Booster decreased waiting times by approximately 30%. The equipment also featured regenerative controllers and gearless drives with permanent-magnet motors in order to fulfill the client’s request for energy-efficient motors and protection against uncontrolled movement in the upward direction. The door operators are closed loop to help achieve faster door opening and closing times, and there are LCD direction and position indicators for all landings and cabins. 

ThyssenKrupp replaced the roller guides and diverter pulleys on the cars and counterweights to enhance riding performance. The elevators are equipped with an automatic rescue device that evacuates the elevator at the next landing in case of a power failure. All interiors were modernized with custom panels, floors and ceilings. All landing floors (88 total) have custom finished cladding with Islamic designs in mirror etched stainless steel.

Thorsten Elsaesser is the modernization manager at ThyssenKrupp Elevator (U.A.E.) With more than 15 years of elevator industry experience, Elsaesser started his career with Thyssen Aufzuege in 1991. He has been involved in a range of modernization projects within the U.A.E. from hospitals to office towers and residential buildings. He graduated from the University of Esslingen, Germany, with Engineering and Business Administration degrees.