Reliable technologies for renovating damaged pipelines, manholes and culverts
Most of the water and sewage infrastructure in Europe are nearing the end of their service life. Numerous investment projects in 1970s and 1980s were based on reinforced concrete, steel and cast iron pipes, which now need continuous repair, renovation or replacement. While repair is a temporary solution and replacement an expensive one, renovation seems a reasonable compromise. Such projects involve, among others, different renovation methods by means of polyethylene pipes.
Uponor Infra is one of the most experienced manufacturers and suppliers of polyethylene pipes since its history goes back to 1950s. Since 1976 the company has also developed pipe systems for renovation of damaged pipelines, used for repairing water pipelines as well as sewage pressure and gravity systems or technological pipelines.
The renovation methods using Uponor Infra systems have become one of the most reliable technologies in the market. The fact that the pipes are made of polyethylene has got numerous benefits. The renovated canal or pipeline is corrosion, abrasion and impact resistant, guarantees long-term operation and is characterized by low roughness coefficient ‘k’. These methods of renovation require installation trenches only, which helps minimize car and pedestrian traffic disturbance. What is more, during the renovation process water and sewer system can normally operate and – in most cases – there is no need for drainage.
Choosing the optimal renovation method
Prior to renovation works, an in-depth analysis of pipeline technical condition is required. Before choosing a particular renovation method one must:
- determine the structural and hydraulic condition of the damaged pipeline
- assess degree of damage to the pipeline
- prepare a detailed calculation of pipeline parameters, including location, side connections, dimensions and material used to build it
- choose the most optimal renovation method.
Uponor Infra can offer a range of several renovation technologies:
Long (sliplining) and short relining with Weholite pipes
Weholite pipes can be joined by extrusion welding, thread joint or snap joint.
In short relining method, short - from 1 to 6-meter long Weholite pipes are pushed through existing manholes or small installation trenches. Weholite modules can be joined by snap joints with a seal, machine installed at the ends of the pipe, or can be thread joined with an additional weld.
Weholite pipes are offered in wide diameter range, from 300 mm to 3000 mm, which allows to customize a given pipe to the requirements of a given project.
Short relining and static cracking with VipLiner modules
Static cracking consists in crushing the old pipe by means of a special head connected with a hydraulically driven head by means of steel rods and simultaneous pushing in of a new pipe. As the old pipe is crushed and new modules are introduced, it is possible to maintain the present diameter of the pipe or even to increase it by approx. 10% of the cross-section.
Long relining (sliplining) and cracking with WehoPipe and WehoPipe RC/RC+
For this renovation method, solid walls WehoPipe PE or WehoPipe RC/RC+ pipes with diameters DN 63 mm – 1600 mm are used. Depending on the condition of the old pipeline and the parameters of the new pipe (DN, SDR, PE), it is possible to slip pipe lengths even longer than 1000 m. The joints are butt-welded. In result of renovation, the inner diameter of the pipeline is slightly reduced. If it is especially important to minimize the narrowing of the repaired pipe, the swagelining „tight fit” renovation method, should be applied.
If it appears that due to its technical condition, the pipeline should be reconstructed or if a new pipe would cause considerable reduction of pipeline capacity, cracking method is used.
Long relining with WehoPipe and WehoPipe RC/RC+
For renovation of damaged pressure pipelines solid walls WehoPipe PE or WehoPipe RC/RC+ pipes with diameters up to 1800 mm are used. The joints are butt-welded. In the long relining method a PE liner is pushed into the old, damaged pipeline. In result of renovation, the inner diameter of the pipeline is slightly reduced.
If it is especially important to minimize the narrowing of the repaired pipe, the swagelining „tight fit” renovation method, should be applied. This installation technology is based on slipping long lengths of a PEHD pressure pipe into an old pipe. The difference is that the diameter of the new pipe is slightly greater than the diameter of the renovated pipeline.
The swagelining method involves reducing the outer PE pipe diameter (by a “hot” or “cold” method) and slipping the pipe through a special reducing matrix using the continuous, controlled pulling force. Deformed PE pipe is pushed inside the renovated pipeline, where, once the pulling force is released the pipe comes back to its original shape, which makes it fit tightly. Pipe within the range DN 75 mm – 1800 mm are used for this renovation method.
Cracking consists in breaking the old pipe by hammer equipment or hydraulic expanders and introducing the new pipe directly after the crushing device. Once the work is completed, the new pipe takes over all the functions of the old collector.
We propose Weholite pipes, used for a long time in the road construction, for the renovation of road culverts. Road culverts built in Weholite technology have very high dynamic load resistance. The properties of their construction material, i.e. polyethylene, give them long service life, complete lack of corrosion and high chemical resistance (inter alia to oil derivatives, salts). Weholite culverts are made from double-wall pipe which ensures high ring stiffness. The pipes are admitted for use in the mining damage areas up to 4th category (inclusive).
Weholite culverts installed in many European countries are an alternative to traditional materials. The culverts are used both under the roads and the railway tracks. Weholite culverts became a standard in road construction in Europe, and specifically in Scandinavia, as the polyethylene is a completely environment friendly material.
Weholite culverts can be installed both with small and very big overburden. The ends of the culverts can be formed in any way accordingly to the inclination of the slopes. Weholite culverts are offered in a very extensive range of diameters, from 300 mm to 3000 mm and in a standard 12.5 m length. At client’s request we can make the culverts of any diameter, length and ring stiffness.
The analysis of technical condition of a collector should comprise the manholes along its route. Their technical condition may also pose the same threats as the collector itself. Even if, before renovation, no infiltration of ground water in the manhole was found, after the collector is tightened, the ground water level may rise and leaks may occur. That is why in the areas characterized by a high level of ground waters, it is worth renovating not only the collector but also the manholes. Depending on the collector diameter and dimensions of existing manholes, their renovation can be performed using the existing range of PE pipe diameters.
Manholes are connected with the renovated collector by extrusion welding. Manholes are either replaced or their upper part is removed and dismantled and a chimney of a shorter diameter is introduced, while the space between the chimneys is filled with sand or cement mortar, depending on the structural condition of manhole.
Support for customised solutions
Do you need a tailor made product, or a turnkey solutions on a global scale? We offer full support within: design & calculations, tailor made products, field services, technical support and project management.