Weholite sopii vesistöasennuksiin: se kestää suolavettä ja korroosiota, hitsausliitokset ovat vesitiiviitä ja toimitusvalikoima ulottuu DN/ID 3 500 mm saakka.

Cooling intake and outfall pipes

Durable pipes for underwater installations

The installation of intake and discharge pipes in water is a multi-stage project, which includes pressure and strength calculations, material deliveries, welding, assembly and the actual installation. Uponor can supply all the relevant services as a complete package.

Weholite is suitable for installation in water: it withstands salt water and corrosion, the welding joints are waterproof, and the available size range reaches up to
DN/ID 3,500 mm. The light pipes – even the large diameters – are easy to install and handle. Flexible pipes adapt better to the load variations of ground water than rigid pipes do.

Conventional polyethylene pipes with solid walls are typically weighted against buoyancy with external concrete weights. This approach can also be used for Weholite pipes, but it is preferable to make use of the pipe's flexible structure by filling the hollow thread profile with concrete mortar. This method saves you dredging costs since the trench needed for a profile weighted pipe is narrower than the one required for outside weighting. Profile weighting is not only quick, it requires less heavy installation equipment, and any related welding can take place at a separate work site. Plumbing components can be towed to the final installation site with pontoons.


Inlet and outlet pipes in polyethylene are corrosion-resistant, water-tight and have a long service life. We have long-standing experience of underwater pipelines and with the Weholite pipe's unique properties in combination with high-level technical expertise we can offer a cost-effective design. Weholite Weholite is a profile pipe with smooth surfaces on both the inside and the outside, developed in the 1980's. It is a HDPE pipe which is suitable for internal pressure of up to 22.5 psi and is one of the few pipes in the world which can be manufactured in sizes up to 132" ID. Weholite is available with an internal diameter of 18" to 132" and ring stiffness classes of up to 400. Pipe lengths are usually 40-50', but can also be delivered in longer lengths, transport permitting. Weholite is eminently suitable for inlet pipes and outlet pipes for water treatment plants, waste-water treatment plants, power stations and various industrial plants. The main advantages of Weholite compared with other materials are that it is extremely strong and resistant to both corrosion and chemicals, which make it the ideal choice for underwater pipelines. The pipes are flexible, which makes it possible for them to adjust to different loads, vibrations, stress and movements in the ground without the pipe being damaged. Weholite has all the technical advantages of the corresponding massive HDPE pipe, but weighs much less, making installation quick and cost-effective. Installation of underwater pipelines Polyethylene floats as it has a lower density than water. This makes it possible to weld the pipes in a convenient, protected location and then tow the pipeline to the installation site by boat. What makes Weholite a really unique pipe system is that it has a profile wall structure which can be filled with concrete. In this way, the pipeline can be weighted and still retain its flexiblity. Internal weighting also reduces the overall cost of the project as a narrower trench can be dredged than is required for pipes with external concrete weights