The job currently being planned, is a further challenge. For the first time a 1000 mm drinking water pipe made of steel is to be renewed. For this special task it was necessary to develop a new roller blade.
The roller blade consists of a basic body, the exchangeable guiding strip with the guiding rollers and roller blade strips, which are also exchangeable. The basic body is intended for pipes with a diameter range of 400 to 1000 mm. The quantity and arrangement of the guiding strips, which hold the old pipe in a stable circular position during the bursting process, depends on the available diameter.
In this case a total of 11 guiding strips with their guiding rollers hold the roller blade aligned to the old pipe. The precisely aligned guidance is important for a clean cut in the pipe sole. During the cutting process the guiding strips take over the task of keeping the circular cross-section of the old pipe in place. In order to make sure this is guaranteed, the positioning of the rollers inside the guiding strips can provide an exact adaption to the actual old pipe diameter.
The cutting process itself is carried out by a 3-step assembled roller blade strip. The first roller blade is an innovative development and will be applied when the old pipe diameter has partially decreased below the diameter caught by the second cutting roller.
The main cutting work is carried out by the second roller blade. The 3rd roller blade allows pipe sockets or repair sockets to be cut apart. The cutting line can be situated at a distance of up to 150 mm from the outer coating of the old pipe.
The roller blade 1000 is equipped accordingly for the renewal of large scale pipes. It’s length of 1600 mm provides a solid alignment in the longitudinal direction. The swivel integrated in the basic body provides an instant pulling force lead.
The pulling forces of up to 2.500 KN are transferred to the roller blade via the Quick-Lock rods, which have a length of 2.200 mm and weight of 220 kg.
The construction work to be carried out has to be carefully planned with a timely preparation. This starts with the production of the machine pit. The set up area with a length of approx. 9 m and a width of approx. 2,5 m should be equipped with a stable and clean layer. For the induction of the reaction forces of up to 2.500 kN (maximal pulling force), which occur during the bursting and installation process, an abutment is required, which needs concreting in advance. To handle the installation and operation of the pipe bursting jobsite a sufficient sized lifting device should be made available.
This preparation work is very extensive, but are relatively mediocre compared to the extent of work being carried out at bore lengths up to 300 m and pipe diameters of over 1000 mm.
The time required for pushing in the bursting rod and for the real bursting and pipe-pulling process, usually 2 days per bore length, is also very low. Therefore the advance planning, careful preparation work and the ability to master the technical and logistical requirements during the jobsite process, are the main factors for completing these jobsites successfully.
The roller blade 1000 from TRACTO-TECHNIK will also make its own contribution in Russia by successfully bursting pipes with larger diameters.