Alphaliner production line for diameters up to DN 1500 now in service

In the market of UV light-curing pipe liners, development has trended towards the rehabilitation of large diameters via DN 1000. The demand for these diameters has particularly increased over the course of 2015. RELINEEUROPE is following this trend to be able to offer Alphaliner users the possibility of serving this interesting market segment.

However, safe installation of UV-cured liners for the rehabilitation of large pipe diameters above DN 1000 is still a new field of application for liner technology. Particular risks can arise on site due to the complex processes and handling involved with heavy liners that must be minimised. It is therefore important that the liners, UV-curing equipment, and the installation process are all well coordinated with each other.

Special Alphaliner1800 and UV-technology for large section pipes.

The DIBt-approved Alphaliner1800 is a liner that RELINEEUROPE has recently developed for the renovation of large diameters and special profiles. This liner features very high mechanical characteristic values. The short-term Young's modulus is 20.000 Mpa while the long-term value is 12.400 Mpa (5% quantile in accordance with DIN EN 1228). This makes the renovation of large sewers with thin wall thicknesses economically viable. Since its introduction to the market in the middle of 2015 the Alphaliner1800 has already been successfully used in renovation projects, both in Germany and abroad. A special glass fibre was used for this new product. that enabled the development of a design concept that combines very good mechanical properties with a high level of transparency. Depending on the UV-curing equipment used, this now makes it possible to cure even large Alphaliners just with UV light very quickly and thus very economically.

These developments in the liners also mean that the UV systems and other equipment also require further development. The application technology must also be coordinated with the on-site installation teams. Errors in the installation of these large diameter sewers can sometimes become extremely expensive.

In its role as system supplier RELINEEUROPE particularly wants to support installers in the solution of these challenges. That is why the company is currently also improving the installation equipment for large and special profiles. For example, a new generation of end packers and a conveyor with a larger automatic folding device are being developed in order to be able to pull heavier Alphaliners into the sewer without difficulty. The currently available conveyors are only suitable for smaller, lighter hose liners. Depending on the length and wall thickness, the liners can attain a weight of 10 – 15 tons. The entire site logistics must be designed to accommodate these high loads.

A challenge for planners: special specification requirements

The requirements involved in the renovation of large diameter sewers also place special demands on the planning and supervising engineers regarding site planning and preparation. The specifications must take account of the particular features of large diameter sewer renovations.

The challenges involved in large diameter renovations are demonstrated even by the apparently minor matter of installing the packer. The installation of large diameter pipes imposes enormous forces on the packer. For example, the force on the end packer for a DN 800 hose liner is about 1.5 tons, while the load imposed on the component during the installation of a DN 1500 is more than double – at 3.5 tons. Securing the packer with simple tension straps, timber wedges or jack screws will hardly be adequate to absorb the enormous forces involved. Health and safety considerations alone are therefore reason enough to consider, and even more importantly to plan safety measures of a whole different order.

Another aspect to be considered is that in order to guarantee a safe and complete curing of the liner material, the UV curing technology must be adapted to suit the larger dimensions. The output of the curing system must be able to guarantee the complete curing of the liner material over the whole liner wall. The liner wall must be irradiated as evenly as possible with UV lamps of a suitable spacing and output. An economic renovation process is possible on condition that the largest possible area is irradiated simultaneously.

More News and Articles