Pega hoists on the construction site of the world's tallest building - Burj Dubai
19 March 2009
Sometimes the most obvious measures, such as height and speed, get the most attention. Pega Hoists already holds two world records for rack-and-pinion hoists - longest single run, at 425 m; and fastest, non-counterweighted, at 100 m/min at full load of 3.2 t -- as a result of its contract at the Burj Dubai. Next month it will add a third: the world's highest - at 625 m base station - permanent rack-and-pinion lift.
As significant as those performance measures undoubtedly are, in the economics-oriented world of project deadlines and budgets, it is not height or speed that is most important. When a contractor is under scrutiny for schedule performance, reliability is critical.
Pega can justifiably claim an accolade in that respect, too. Four of its 3240 BD VFC double-caged hoists have been climbing to 425 m with loads of 3.2 t at a speed of 100 m/min for 24 hours a day, seven days a week, for more than three years.
In total, that service has been more than 35000 hours, Pavel Policar, industrial and special projects director for Pega and the manager of Pega's Burj Dubai activities, tells AI. "No major breakdowns, all key original components." He says that the hoist traffic over the three years "...corresponds to over 20 years on any other site, for example, in the UK."
Pega met the project's reliability challenge with daily, weekly, and monthly maintenance programmes, developed in conjunction with site operator and Burj Dubai joint venture member Arabetc. It also positioned a "special" stock of spares and consumables on site and elsewhere in Dubai.
The Czech company also cites "superb" personal relations with Mr Reyad Awwad, Arabtec's project manager, and other key project participants. "We all were on the job 24/7, just as were the machines, and there was no problem that we could not overtake fast and smoothly," said Mr Policar.
At the height of construction, Pega had 15 hoists on the tower (see diagram). In addition to four double-caged hoists rising from ground level, two other double-caged hoists of the same type, based at 425 m, lifted to 625 m (floor 160). Three smaller, single-cage "jump" hoists, also mounted at the 425 m level, travelled 80 -120 m to handle the most intense inter-floor traffic. The last one is still there at the very top.
As you can imagine, optimising the flow of materials and workers (8000 at project's peak) up and down the 625 m of the structure served by the hoists was critical to Arabtec. Pega helped design and optimise the traffic scheme as part of its US$4 million (€3.2 million) contract with its client.
The last hoist at the base of the tower came down in October, and two other hoists will remain on the tower for a few months. Now is the "end game" of Pega's involvement. Soon it will install the permanent Pega IL 1012 model hoist to service the radio transmitters, GSM amplifiers, antennas, and other gear going into the steel spiral that will crown the 800 m iconic landmark.
Part of Mr Policar's mission in November was placing that 1 t capacity hoist to the highest-ever position on earth -- over 630 m. Its installation awaits placement of the spiral itself, whose weight will significantly compress the supporting structure.
Pega developed its hoist technology five years ago. It was proven at tall buildings, but not at such as the Burj Dubai - none existed. During the final bidding process the selection committee asked Pega chairman Rudy Vanecek: "How many buildings like this have you helped build?" He promptly replied, "None! And how many of buildings like this you built, gentlemen?"
Mr Policar compares Pega's work at the Burj Dubai to climbing Mount Everest: "There is only one Mount Everest and for anyone there is always the first time. To get to the top of Mount Everest, one has to be modest enough and objective. For two years we performed pre-bidding technology checks, calculations, etc., just to be sure that we were up to the project.
"Getting the project was only some 20% of the effort. The real achievement was to successfully complete the mission and to feel the weight of reputation on site. Obviously, even if you are very good in climbing, Mount Everest teaches you a lot and pushes you miles ahead."
Mr Policar said his biggest surprise during the project was how intense the vertical traffic really was - and how well over the three years the machines coped.
The machines, yes, perhaps the most apparent stars of the project. With job completed, where are they? Pega said the machines are being serviced and will soon hit another project - this time "only" 400 m high.