RAMMING METHOD
Dynamic ramming method uses unsteered ramming with pipe propulsion along with the use of a pneumatic pipe ramming machine. With these, open steel pipes can be laid beneath railway tracks, highways and rivers, either as protection or product pipes, with diameters up to 2000 mm for lengths of up to 80 m in the soil without using pressing abutments. The ram is driven by compressed air and has cotter segments to establish a connection between the machine and the pipe. Due to the two gaps in the soil removal cone or adapters, part of the tension of the spoil carried along, is released. The application of cotter segments prevents the pipes from flaring up and enables high quality butt welds of the single pipe lengths. The casing friction of the inner or outer pipe is reduced by bentonite cutting shoes that simplify pipe propulsion by lubricating the pipe. The minimal displacement volume in the area of the cutting shoe eliminates the risk of road surface heave, and means that work can commence even from shallow pit depths. Advantages of the method include surfaces worth conserving are not broken, restoration is not required, low social costs, acknowledged procedure, short set-up times, short pipe laying times, no pressing abutment, no conveyor spiral, no flooding when working on river crossings, minimal covering, no elaborate pits, simple operation technique and adaptation to all pipe diameters with a special ram cone.
TRENCHLESS PARALLEL NO-DIG TECHNIQUE
The trenchless parallel no dig technique is a further developed and refined version of the water flush drilling method that has been developed by Stadtwerke Schwerte GmbH. It solves the problem of space availability for all sorts of utility lines by considerably reducing space both above and below ground, thus making it possible to lay a bundle of pipes in a one step operation without twisting and trenches in precisely defined distances.
TRENCHLESS PIPE REHABILITATION
Trenchless pipe rehabilitation refers to the method of trenchless pipe replacement through the renewal method which includes:
DYNAMIC PIPE BURSTING
In the method of dynamic pipe bursting, the bursting machine is pulled by a winch through the old pipe meant to be renewed. During this procedure, the old pipe is destroyed by dynamic impact energy and the fractured particles are pushed into the surrounding soil, while the new line, in the same width or one size larger, is pulled in at the same time.
PIPE EATING BASED ON MICROTUNELING
Pipe eating is a replacement technique based on microtunneling, where the defective pipe is excavated together with the surrounding ground, as it would be for a new installation. The pipe eating shield is pushed forward along the route of the existing pipeline using hydraulic jacks, located in the drive shaft. The replacement pipes are connected to the back of the tunneling shield. On completion of the drive length the pipe eating shield is recovered at the reception shaft, leaving a new pipeline in place of the defective pipe.
PIPE EXTRACTION METHOD WITH GRUNDOBURST
Pipe extraction method with grundoburst is the method wherein damaged gas and water lines, can be easily replaced by new pipes in the same bore path.
PIPE SPLITTING METHOD FOR TRENCHLESS PIPE REPLACEMENT
Pipe splitting method solves the problem of lead pipes being replaced by plastic pipes to supply potable water. This method was developed by the Water Supply Company of Berlin, in order to carry out trenchless lead pipe replacement within the field of house connections.
STATIC PIPE BURSTING METHOD
Static pipe bursting method with the patented Grundoburst is used to replace old pipes, especially in sensitive soils within the vicinity of other external lines. It is often used for the renewal of potable water lines where stems are pushed through the old line first. The old pipe line is actually cut open by the roller blade immediately followed by the expansion head. Advantages of this method include: path of the old pipe can be used, bursts grey cast iron, asbestos-cement, stoneware, concrete and plastic, pipe bursting can also cut ductile grey cast iron and steel new pipe with new longevity improvement of the hydraulic capacity, because the new pipe to be installed is 1 or 2 sizes larger, no reduction of the cross section, applicable for all types of damage, good bedding conditions, short equipping time and simple operation technique, high daily capacity of up to 150 m.
