ISIK Engineering Ltd. Co. was recently awarded a Eur 14.7m contract to supply six ladle crane units of 320t, 75t and 10t capacity - with 320t ladle lifting and 75t and 10t auxilliary lifting capacities - for ISDEMIR Iron and Steel Works in Turkey - a venture of the ERDEMIR Group.

The order was received in February 2005 and the last of the cranes will be delivered later this month (July). It may sound like a long time, but there were a host of complications that needed to be overcome.

The scope of the project included basic and detailed design, manufacturing, transportation, site erection, start-up and commisioning of the cranes. ISIK completed all of the mechanical, electrical and automation engineering itself. Cranes were frequency controlled, equipped with anti-collision systems, load cells and PLC controlled. Automation engineering included PLC software. Sub-contracted work included the machining of 320t drums, trolley frames and lifting beams.

ISIK described the project as a challenging one with a variety of complex elements making lifting difficult. For example, the design of the cranes needed to be unique in order to operate in confined spaces - at speed. The 320t hoisting reached 10m/min, while 75t hoisting took place at 10m/min. The main trolley traversing was 30m/min, as was auxillary traversing. The crane itself, travelled at 80m/min.

ISIK founding partner Gurel Gencer said: "After an early elimination period our company was selected as one of the participants for the international bid [in which international companies such as Konecranes and Kranbau Koethen also participated]. Since we gave the best price among the participants we received the order."

It was no mean feat to out-gun the bigger companies - but this was the easy part.

The overall project schedule was short. In fact, all of the cranes were to be delivered in an 18 month period - this included the manufacturing, transportation, erection and start-up of these giant cranes. All of the large components, including rope drums, trolley frames and lifting beams had to arrive on site within this time frame.

One of the biggest problems was the difficulty in transportation, due to the size of the crane components, to Iskenderun, which is 600km from the production plant, which is located in southern Turkey, close to the Meditteranean. Also of concern during the planning stages was the site erection of the cranes. Lifting and completing the erection of the main girders (110t each) and main trolley (170t) to the crane runway, which was 36m above, needed serious attention and a strong mobile crane.

Gencer explained: "The problems were overcome in advance but we experienced some timing problems due to a limited number of alternatives for turning and boring machines, transportation vehicles and mobile cranes."

ISDEMIR and ERDEMIR plants are investing to increase their total output to seven million tons by the year 2007. Gencer says the most critical cranes within this investment are the 320t capacity machines. He adds that ERDEMIR Group is the biggest steel group in Turkey. ISDEMIR is the second largest plant in terms of total capacity but the largest plant in terms of long products capacity.

According to ISIK, this is the biggest crane project, both from an engineering point of view and financially, ever seen in Turkey.

The cranes were four girder and two trolley cranes - two of them with 28m span and four with 21.5m. They had approximately 30m of lifting height and limited space within which to operate considering the height and width of the units. ISIK says it was able to fit the crane to a maximum height of 5.8m and maximum width of 20m. They consisted of one main trolley and one auxilliary trolley. The main trolley carried the 320t hoisting group and the ladle beam underneath. The auxiliary trolley carried two hooks - one of 75t and one of 10t capacity.

The main hoisting group is equipped with two drums of 1,750mm diameter and 6m length. Emergency drum brakes are installed against any failure in the mechanism. The cranes are equipped with a differential main hoisting gearbox, which enables them to operate the crane in half speed in case of failure of one of the main hoisting motors. Anti-collision devices, load cells for weighing and central lubrication systems were some of the other systems that were used on the project.

Frequency controlled regenerative stepless speed drive system and PLC was also used. Electrical panels were located in an air conditioned electrical panel room since the ambient temperature is 70 degrees centigrade.

Four of the cranes have already been delivered, three are already erected on the site. The last two cranes will be delivered later this month. The commission date is expected this month (July) and the cranes are expected to be operational in August. They have an ISO m5 duty rating.

Gencer says: "We specialise in tailor made cranes. Since the number depends on many factors such as capacity and span etc it is not easy to give an annual output quantity." ISIK Engineering Ltd. Co. has manufactured 44 steel mill cranes since it was formed five years ago to both Turkey and abroad - mainly to European countries.