Kobelco SL6000 - Bok Seng
Bok Seng from Singapore (SG) was using this sharp Kobelco SL6000 to lift a component of a tunnel boring machine (TBM). It is a 550-tonne crawler crane from year of manufacture 2008.
The undercarriage is 11.49 meters long and 9.9 meters wide. The tracks are 11.49 meters long, 1.5 meters wide and 1.79 meters tall. The mass each is 40 tonnes.
The crane is powered by an Hino E13C-UV, a 12.9-liter 6-cylinder diesel engine with a power of 320 kW (439 hp). The diesel engine powers in total six hydraulic pumps.
Attached to the superstructure is a counterweight of 180 tonnes, the counterweight exists out of a 20 tonne base plate and sixteen slabs with a mass of 10 tonnes each.
Attached to the carrier is a total of 50 tonnes of central counterweight, 25 tonnes per side.
The lifting- and adjustment winches are fitted in the boomfoot sections of the main boom and superlift. The crane is fitted with two 14-tonne hoist winches. The boomfoot of the main boom has a mass of approx. 29.3 tonnes.
Here was the crane fitted in HL configuration, with the 300-tonne boom head. The length of the main boom is minimum 30 meters and maximum 84 meters long. On this job was the crane fitted with a 36 meter long main boom.
This boom head is also required when the crane is used with a luffing jib.
The rigging for the lift is prepared. The 300-tonne hook is reefed at 24 part lines.
The load is going to be this section of a TBM with a mass of approx. 156 tonnes. The TBM has a 7.56 meter diameter and will be used to drill a tunnel for an underground sewerage system. This part will be used to push the TBM forwards with the hydraulic cylinders.
As assist crane was a Liebherr LTM 1500-8.1 also of Bok Seng used. The crane was fitted with 135 tonnes of counterweight.
The load is hooked on, time for some action!
The superlift has a length of 30 meters. The counter radius is to choose at 11, 13 or 16 meters.
The load is now hanging in both cranes and is beeing tilted.
The load is now transfered to the SL6000, in total is now hanging 173 tonnes in the crane, that is inclusive of 17 tonnes for the hook and rigging. In Singapore is for such projects a safety coefficient of minimum 1.25 requested; the crane should be configured in such a way it is able to lift a load of approx. 217 tonnes.
The crane is slewing the load above the shaft and the superlift counterweight is attached to the superlift.
The load is boomed down to a radius of approx. 24 meters.
The superlift counterweight has a total mass of 191 tonnes, the maximum superlift counterweight is 250 tonnes.
The load is lowered to a depth of approx. 50 meters and will be connected with the rest of the TBM. A very sharp job by Bok Seng!