The DS short liner is a procedure for sewer repair and is especially appropriate for sealing and/or supporting the stability of sewer sections. The result of the rehabilitation with the short liner decisively depends on the adhesion primer preperation and the quality of the used materials. One preferably utilises support materials of FRP which are impregnated with a methacrylic resin and provide an installation which is safe and reliable.

The procedure can be applied for defective sewers whether circular or egg-shaped in every current line material and cross section between DN 100 and DN 800. The defects to be rehabilitated are in particular cracks, shards, missing wall parts and leaky pipe joints.

As soon as the preparation and the cleaning of the place to be rehabilitated are done, the FRP support material is impregnated with methacrylic resin (MMA) and mounted on a packer. After the positioning (controlled by camera) of the packer at the damaged spot, the packer system is supplied with compressed air and expands to the size of the internal diameter of the pipeline.

The short liner is thus pressed against the wall of the old pipe and cures under constant pressure. At the end of the curing process the pressure of the packer is released, the packer system is withdrawn and removed from the pipeline. The damaged spot is rehabilitated and the finishing work can begin (opening the branch, camera documentation).

Especially the adhesion to wet and difficult surfaces is one great advantage of this system and the utilised materials. Moreover, the time to work the resin is quite long and takes more or less 25 minutes considering a curing time of approx. 40 minutes. With our D&S short liner, longer rehabilitation sections can also be carried out, as the overlapping of the short liners creates a socketless pipe section over the entire damaged area. And in addition the product has a high resistance against a multitude of chemicals, acids, bases, oils, greases and detergents.

The top-hat profiles are used for the integration of inlets during hose lining or for the partial renovation of an inlet in combination with a short liner. Depending on the inlet geometry, top-hat profiles consist of a prefabricated carrier material with a collar at least 5 cm wide that covers the integration area in the main sewer and a hose liner piece at least 10 cm long that projects into the inlet pipe. The carrier materials consist of synthetic fibre felt, which is impregnated on site with a multi-component resin system.

Top-hat profiles are mainly installed in connection with renovation measures (inliner renovation) of main sewers, but also for partial renovation of cracks in the connection area in combination with a short liner. The nominal width range in the main sewer extends from DN 200 to DN 800 (circular profiles) and DN 100 to DN 200 in the connection pipes. Depending on the system, installation in egg-shaped profiles is only possible to a limited extent and in the upper section of the profiles.

Obstacles must be removed in advance. For a permanent bonding or adhesion a preparation of the surface by means of robot technology is necessary. Film surfaces must be removed by grinding or brushing. After impregnation of the top-hat profile laminate, the top-hat profiles are positioned in the main channel at the inlet, depending on the system, with special inlet packers or with robot crawler and top-hat setting device. Through expansion, the laminate is pressed against the pipe wall in the main channel and in the connection pipe. Depending on the system, the curing of the reactive resins takes place through ambient temperature or thermal support and bonds the cap profile to the liner or old pipe.

Within the scope of the inliner renovation, the transition area from the inliner to the house connection pipe is connected in a backflow-proof and watertight manner by means of surface bonding. The top-hat profile enables the repair of cracks in the connection area during partial renovation. Flexible use with different connection angles is possible

The internal pipe sealing systems of Pipe-Seal-Tec GmbH & Co KG can be used for the partial repair of damaged areas and leaking pipe connections as well as for the tight connection and protection of the liner ends at the shaft, the so-called liner end connection. The internal pipe sealing systems Pipe-Seal (stainless steel sleeve with locking mechanism and EPDM seal) and RedEx® (EPDM pressure sleeve) can be used independently of the old pipe material, even in the case of strong infiltration or difficult adhesive base.

The Pipe-Seal stainless steel sleeves Pipe-Seal-Fix or Pipe-Seal-End can be installed in the nominal width ranges DN 150 - DN 800 both as an internal pipe sealing system and as a liner end sleeve in circular pipe profiles. The one-piece stainless steel sleeve Pipe-Seal-Flex can be used in the nominal width ranges DN 200 - DN 600 with axial deviations of up to 8°, pipe offsets of up to 30 mm and with one-sided conical expansion of up to 30 mm also as a liner end sleeve. Larger damaged areas can also be rehabilitated in a so-called overlapping serial offset. All Pipe-Seal stainless steel sleeves can be used in gravity sewers and also in industrial applications at temperatures from -20°C to +140°C.

The RedEx® EPDM (pressure) sleeve can be used in non-accessible pipes from DN 190 - DN 700 for liner end connections and from DN 800 - DN 6000 in accessible pipes as an internal pipe sealing system. From a minimum nominal diameter, the use is also possible in egg-shaped profiles. With the special solution RedEx®-Connect, in addition to the standard widths 260 mm, 360 mm and 500 mm, longer damaged areas in series and conical pipe connections can be sealed. The RedEx® system can also be used in pressure pipes and drinking water systems in addition to open-channel lines for municipal wastewater with specially approved elastomers. 

The Pipe-Seal stainless steel sleeves are fixed on special so-called liner and relocation packers and precisely positioned at the damaged area with the help of TV or robot technology. With the help of compressed air, the stainless steel sleeve expands under defined contact pressures. Two locking mechanisms, each located in the sleeve, engage in their position on a toothed bar in accordance with the direction of movement, so that the external elastomer seal permanently seals the damaged area.

RedEx® (pressure) sleeves are made up for each nominal size on a project-specific basis and positioned on the damaged area or at the end of the liner. With the help of the stainless steel rings and a hydraulic tool, the RedEx® sleeve is permanently and permanently tightened by hand. RedEx® cuffs can also be uninstalled as required.

Pipe-Seal-Tec GmbH& Co.KG's internal pipe sealing systems can be installed in almost all pipe materials, with almost all types of damage and regardless of the reason for adhesion, even in case of strong infiltration, simply and quickly without waiting times in the cleaned pipe. In addition to an extremely wide temperature range between -20°C and +140°C, the products are also highly resistant to a wide variety of chemicals, acids, alkalis, oils, greases and cleaning agents.