Drilling with Robit DTH SF down to the bedrock, steel pipes are connected to eachother with pre-welded interlocks building up a waterproof wall. The company touts the pipe pile walls as having excellent bending stiffness and resistance. Robit DTH SF for Pipe-Pile Walls are suitable for use in applications including retaining wall structures, building foundations, wharves and piers, road and railway structures, and bridges. www.robit.fi