When faced with a couple of challenging lifting projects in its local region of Valladolid, Spain, crane rental company Tinlohi called on two of its most dependable performers to get the job done a 250 t Grove GMK5250XL-1 and 400 t Grove GMK6400.
Alberto Lozano, commercial director at Tinlohi, said that while both cranes offer class-leading capacity and reach, it was their smooth control and reliable performance that made them prime picks for the projects.
“For each of the jobs, the weight of the load was not really an issue. The challenge was the size of the components and the complications of local conditions,” he said. “We already knew we wanted to use two cranes for each project, and they had to be dependable so, it was an easy choice to select the GMK6400 and GMK5250XL-1.”
The first job took place in Palencia, in northwest Spain, where the pair were able to dismantle a wind turbine in just one day – including all the preparation. The GMK6400 was rigged with 35t of counterweight to support its maximum 60m boom plus a 30m fixed jib. It lifted just over two-thirds of the load. Alongside it, the five-axle GMK5250XL-1 was also rigged with its maximum boom of 78.5m and fitted with a 9.4m jib. The counterweight was 30.5t for the GMK5250XL-1 to manage its role in supporting one-third of the load and the components were lowered from a height of 90 m.
“Although each load was only 11t, the 36m-long turbine blades were too tricky to handle using just one crane,” Alberto Lozano said . “It goes without saying that local site conditions were windy, and the unusual profile of the turbine blades made them complicated to handle. They taper from a 2m diameter where they join the hub to virtually nothing at the tip. We talked to Manitowoc, and the company developed a lift plan which worked perfectly. Despite local conditions, unusual loads, and coordinating two cranes at once we got everything wrapped up easily inside one day.”
For the set up on the wind farm, the GMK6400 was located next to the turbine mast, where it could support the extra weight and lift at a 24 m radius. The GMK5250XL-1 was then set up 16 m away to lift at a 22 m radius.
Team up to tear down
Less than an hour’s drive south of the wind farm in Valladolid, the two Grove cranes reunited again for a complicated dismantling task. This time the load was heavier, with each crane bearing an equal share of the burden as they removed a 55t drying tube from a gasification plant. With boom length set to 40m, the GMK6400 employed 45t of counterweight, while the GMK5250XL-1 was configured with 62.5t of counterweight and a 41.2m boom.
“This was another challenging project, as we had to coordinate the swing of each lift to pass the tube section between silos into the staging area,” said Lozano. “Nevertheless, all of the work – including preparation – was completed without a hitch before lunch.”
In spite of the GMK6400 having the strongest load chart on six axles and the GMK5250XL-1 having the longest boom on five axles, these two cranes prove something much more than their headline features.
“These Grove cranes are so versatile. On the turbine project it was vital that the descending speed of each hook block was the same to avoid the load slipping off,” concluded Lozano. “We were able to ensure this thanks to the efficient control systems on the cranes. The operators were able to work in perfect harmony, to ensure each job was completed smoothly, quickly, and safely.”