Pipe Reduction with the GRUNDOBURST System
Since the 1980’s it has been recognised that pipe bursting technology is a safe and reliable pipe renovation method. The GRUNDOBURST pulling rig combined with the QuickLock rods has continually proved itself in the most difficult applications and jobsite conditions and now as well as ‘pipe string re-lining’ and ‘tight in pipe’ methods, there is another trenchless application to add to the list.
The Pipe Reduction method is used in the rehabilitation of gas, water and sewage pipes which have reduced flow capacity and impaired structural integrity due to aging, cracking, wear and tear and corrosion etc.
The TT Pipe reducer guides the PE pipe string and connects to the QuickLock rods. During the pulling in process, the outside diameter is reduced by about 5-12% of the original pipe’s pre-formed size. Tension is then relieved and the new pipe adapts close-fit to the old pipe’s inner wall. Close fit installation means no annular space remains between the host pipe and the new pipe.
Five reasons for pipe reduction
The pipe reduction method is beneficial for the:
- Repair of pipe leakages, cracks, aging, wear and tear, pitting and corrosion etc.
- The rehabilitation of old pipelines which have reduced flow capacity and impaired structural integrity
- The installation of a mechanically robust new pipe up to OD1200 in pressure steps SDR 17 and 11 in lengths up to 1,500m
- The increased capacity of a pipeline network with increased flow volumes, e.g when required by a growth in the population
- The prevention of unnecessary traditional open trenching and increased civil engineering works
- Features and Benefits of the pipe reduction method
- Due to the close fit installation, no annular space remains between the inside of the host pipe and the outside of the new PE pipe
- The installed PE pipe is industrially manufactured; factory tested and has defined material characteristics
- The effective diameter of the host pipe is only slightly reduced, at the same time the hydraulic capabilities of the new pipeline are improved
- The contractor/customer gains a mechanically robust and new pipe with an extended service life
- Shorter construction time and civil engineering works, results in minimal delays to traffic flow and reduced disruption to the public
- Costs are considerably lower than traditional open trenching methods
- PE pipe tension measurements are possible using the GRUNDOLOG tensile load measuring system