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Milling and smoothing |
(Image: Repair of a projecting lateral with KA-TE system - milling of the projecting lateral until it is flush with the internal pipe wall [FI-Kunsta])
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(Image: Repair of a projecting lateral with KA-TE system - milling of the projecting lateral until it is flush with the internal pipe wall [FI-Kunsta])
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(Image: Repair of a projecting lateral with KA-TE system - after completing the milling works [FI-Kunsta])
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(Image: Repair … |
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Milling and grouting |
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(Video: KA-TE robot: Milling robot) |
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(Video: KA-TE robot: Sleeve-placing and grouting device) |
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(Video: Repair of a recessed lateral with the KA-TE system [FI-Kunsta]) |
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(Video: Schematic illustration of a grouting system consiting of a folding saddle and a packer)
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(Image: Rehabilitation of a lateral inlet - view of the retracted packer) |
(Image: Rehabilitation of a lateral inlet - expanded packer) |
(Image: Rehabilitation of a lateral inlet - rehabilitated lateral inlet) |
(Image: Rehabilitation of a lateral inlet - mixing plant for mixing the fibre-reinforced dry gorut) |
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(Image: Milling of a crack by means of the KA-TE-milling robot)
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(Image: Milling of a crack by means of the KA-TE-milling robot)
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(Image: Grouting of the crack by means of the KA-TE-smoothing robot)
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(Image: Smoothing of the grouted crack by means of the KA-TE-smoothing robot)
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| (Image: Pros and cons) | Advantages of robot processes: - no or only few obstructions of public transport
- no excavation necessary
- low emissions
- repair of almost all damages of sewers possible due to the manifold functions of the robot systems
- no reduction of nominal size
- no or only temporary interruption of drainage capability during the repairing works
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| (Image: Pros and cons) | Disadvantages of robot processes: - the purchase costs of the equipment are relatively high
- high level of operator skill required
- a precise evaluation of the damage necessary
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Sealing processes are understood to be measures for the local sealing of sewers to restore the leaktightness and, if necessary, to stabilise the load bearing capacity. | |
(Image: Structural calculation)
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(Image: Leaktightness)
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| (Image: Overview of the sealing processes from inside by means of internal sleeves)
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This process group is characterised by a woven sleeve soaked in synthetic resin, which, with the aid of a packer that is inflatable by air, water or steam, is transported to the damage location in the sewer and pressed against the internal wall of the sewer and is then hardened in situ while the pressure of the packer is maintained. (Video: Working steps in the installation of a short liner) |
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(Image: Synthetic resin-based short liner - Packer with … |
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These are the application fields of short liners: | | (Image: Parts of section)
| (Image: Discrete pipes)
| | (Image: Pipe joints)
| (Image: Branch connections)
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Short liners are used to eliminate the following damages: - radial cracks,
- longitudinal cracks,
- fragmentation,
- holes, or
- leaky pipe joints
Short liners are suitable only to a limited extent for the following damages: - positional deviations,
- cross-sectional deformations,
- flow obstacles, e.g. root ingress.
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(Image: Root ingress in the region of a pipe joint [FI-KMG])
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(Image: Fracture in a vitrified clay pipe; pieces are still in place [FI-IfK])
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(Image: … |
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| (Image: Attention!)
As a first step, the flow obstacles that may obstruct the pulling-in or expanding of the packer must be removed. | |
Working steps for the installation of a short liner on the basis of synthetic resin: - The section to be repaired as well as the laterals are placed out of operation and (HD)-cleaned; the subsequent TV-inspection serves to accurately measure the position of the damages and branch connections.
- The short liner is dimensioned, …
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Working step 1: (Image: Water jetting and vacuuming vehicle for cleaning sewers)
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(Image: Soaking of the short liner)
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(Image: Soaking of the short liner)
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| Working step 3: |
(Image: Wounding of the soaked short liner around the de-aerated packer)
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(Image: Wounding of the soaked short liner around the de-aerated packer)
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| Working step 4: |
(Image: Insertion of the packer with the soaked short liner into manhole)
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(Image: Hardened short … |
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| (Image: Pros and cons) | Advantages of short liners: - no earthworks necessary
- no traffic obstructions
- the large range of packers enables repair work for nominal sizes of DN 100 up to DN 800
- constant camera control of repair works
| | Disadvantages of short liners: - formation of folds due to wrong dimensioning and packing or badly soaked carrying materials
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Internal sleeves are elastomeric profiles that are fixed in the sewer by means of tension rings or stainless steel sleeves that are sealed by elastomers or glued to the sewer walls by means of reaction resins. |
(Image: Stuttgarter sleeve – view of the V2A sleeves in the tunnel profile DN 150 to DN 350)
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(Image: Overlapping and pre-tensioned internal sleeve (Quick-Lock-V4A-process))
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These are the application fields of internal sleeves: | | (Image: Discrete pipes)
Discrete pipes | (Image: Pipe joints)
Pipe connections |
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Internal sleeves are used to eliminate the following damages: - radial cracks,
- longitudinal cracks,
- fragmentation,
- holes, or
- leaky pipe joints
Internal sleeves are suitable only to a limited extent for the following damages: - positional deviations,
- cross-sectional deformations,
- flow obstacles, e.g. root ingress.
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(Image: Root ingress in the region of a pipe joint [FI-KMG])
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(Image: Fragmentation of a vitrified clay pipe)
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(Image: Fracture of PE-pipe … |
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Sealing effect: the pressing on of an elastomeric sleeve with sealing beads |
| (Image: Overlapping and pre-tensioned internal sleeve (Quick-Lock-V4A-process)) |
(Image: View onto the sealing beads of the installed internal sleeve of steel) |
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| (Image: Completely installed internal sleeve in the sewer) |
(Video: Installation of the internal sleeve [FI-Rausc]) |
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Sealing effect: Gluing of stainless steel sleeve to the internal sewer wall by means of a two-component adhesive on the basis of epoxy resin | |
(Image: Packer on the trestles)
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(Image: Preparation of the sleeve - Packer with sleeve placed over it)
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(Image: Preparation of the sleeve - Final fixing of the sleeve by means of adhesive tape)
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(Image: Preparation of the sleeve - Applying the resin on to the later overlapping part of the sleeve)
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(Image: … |
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| (Image: Pros and cons) | Advantages of internal sleeves: - long service life of stainless steel sleeves
- pipe sections that have strong static damages, even with a strong groundwater infiltration, can be rehabilitated by stainless steel sleeves without losing their material quality [FI-Geige].
| | Disadvantages of internal sleeves: - high material costs (stainless steel)
- reduction of the discharge section
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This lecture is part of the series "Trenchless 101" and serves to provide an overview of trenchless repair methods for gas, water and wastewater pipelines. |
