The static pipe bursting method is recommended for the trenchless renewal of gas and potable water lines in sensitive soil conditions, where other external lines and buildings are within the immediate vicinity.
Static pipe bursting method with long pipes
When replacing pipes with the static bursting technique, a bursting rod is pushed from a start pit (shaft) through the old pipe into a target pit (shaft). On arrival in the target pit the bursting blade with the new pipe connected is attached to the rod string. When pulling back the rod string the old pipe is destroyed by the blade, the pipe fragments are displaced into the surrounding soil and the new pipe - of equal or larger diameter - is pulled in simultaneously. Usually long plastic pipes are pulled in - in narrow spaces also short pipe modules can be installed.
A common application form is the renewal of pipes from pit to pit. The maximum distance between the pits (often house connection pits) is 200 meters. Shafts along the path are simply passed through.
Special forms of application are the pipe extraction technique and the TIP-technique.
The hydraulic GRUNDOBURST, produced by TRACTO-TECHNIK, has proved its outstanding reliability. Five Grundoburst models of different power classes are available. The GRUNDOBURST- system consists of a robust bore rig, a hydraulic power unit and the QuickLock bursting rods. The system is easy to install and operate. This means, the equipping time is so short, it can almost be ignored. With a daily capacity of 200 m and more, the GRUNDOBURST can achieve peak values.
The bore rig is telescopic and can be extended hydraulically from 1.20 m to 1.90 m as a support in the front of the pit wall. The bore rig is fastened securely to give the rods a sure guidance. The operator stands on top of the unit and not at its side, so the pit needs to be no wider than 60 cm. It is clever to install the starting pit halfway between two target pits, so you can work in both aligning directions from one pit without having to change the position of the bore rig. After the QuickLock bursting rods have been pushed into the first main, they are not
This saves you a further working step, lengths of more than 200 m are easily achieved. Laterals require intermediate pits. Slight bends of the old line are no problem for the supple QuickLock bursting rods.
QuickLock bursting rods
The QuickLock bursting rods are ladder-shaped; they are not screwed, but simply clicked together, absolutely stable towards pulling and pushing. This saves a lot of time, because the thrusting and pulling in process is not interrupted. Compared with the 70 cm long QuickLock bursting rods, it takes a lot of time to screw and unscrew conventional round threaded rods. Also, the power is not safely transmitted, not to mention wearing out the threads with numerous screwing operations. Also the threads inevitably get dirty.
Obstacles in the old line can be overcome with the available thrust force, 275 or 610 kN, depending on the model. A winch is not required for static pipe bursting. When pushing in or pulling out the rods, you can switch over from manual to automatic mode. This saves time and a second operator.
After the rods have been pushed in, the bursting operation commences with the pulling in of the pipe. In the target pit, the guiding head is replaced by a roller blade with expanding head and the new pipe attached. A joint makes coupling with the pipe string easier, and guides it in the required radius. The old pipe is destroyed by the roller blade running ahead when the rods are pulled back. The expansion head, following immediately, pushes the shards of the old pipe away, expands the bore hole and smoothes the bore channel. To make the following pipe assembly easier, the rollerblade and the expansion head with the pipe can be pulled through the frame of the bore rig right into the pit. You can pull in the pipe straight from the pipe coil, welded together as a pipe string, or as a short pipe.
Static pipe bursting method with short pipes
All advantages at a glance:
- applicable in sensitive areas without dynamic impact to the ground
- one machine for supply lines of diameters from DN 80 upwards
- also suitable for renewing steel pipes and ductile cast iron pipes
- articulated QuickLock bursting rods
- no time-consuming screw thread turning of the rods, but simple QuickLock coupling
- interlocking thrust and pull connection
- high thrust and pull back force
- no winch required
- very simple handling (only two persons necessary)
- short assembly time - simple installation
- 150 - 200 m daily capacity
- easy transport. on a small truck permits taking a PE pipe coil trailer along at the same time
- PE-pipes can be pulled in soil-free directly from the hosereel