Liebherr LRB 255 - Sterk
Sterk from Drachten (NL) was using at the end of 2009 this interesting Liebherr LRB 255 with year of manufacture 2004 on a project in Leeuwarden (NL). This machine was rented by Sterk directly from Liebherr.
The LRB 255 was at that time the largest drilling rig from Liebherr. Today that is the LRB 355.1. The operational weight of this machine is approx. 95 tonnes with the tool in the leader.
The machine is powered by a MAN D2842LE, a 12-cylinder diesel engine with a power of 605 kW (811 hp). The engine powers in total five hydraulic pumps.
The undercarriage is 5.89 meters long and 4.7 meters wide. For the transport over the road is the width to be reduced to 3.49 meters.
The counterweight is 12.5 tonnes and has a 4.23 meter tailswing.
The leader can be adjusted in an angle of 1:6 forwards or 1:3 backwards.
In the leader is hanging a Liebherr BVV 32 VM ring vibrator with a mass of approx. 12.5 tonnes. The pile with a maximum diamter of 610 mm is clamped and vibrated into the ground.
When the pile can't be lowered anymore with the vibrator is the pile driven with the Kobelco BM700. Once reaced the right depth is rebar mounted in the pile and filled with concrete. Then, the LRB will vibrate the pile out of the ground again. An interesting job by Sterk!