Description of a trenchless rehabilitation method
Maintenance and repair
according to PN-EN 752-5; 13689
1. DESCRIPTION OF A SEWER PIPELINE CLEANING AND MAINTENANCE TECHNOLOGY USING HYDROKINETIC METHOD
The hydrokinetic method of cleaning and maintaining sewer lines consists in introducing a water hose with special cleaning heads inside the pipeline. The hose is pulled into the line by the jetting force of the water leaving the head under high pressure. The method is designed for cleaning pipelines of diameter from 100 to 1200 mm.
There are two kinds of high-pressure equipment:
- standard pressure (operating on pressure up to 200 bar)
- hydromonitored (operating in 700-1000 bar pressure range)
The type of unit and head depends on the type of pipeline, type of the deposits present there and their thickness and the reasons behind the cleaning process. A single section that can be cleaned can be 100 to 500 m long, depending on many factors, such as: horizontal layout of the pipeline and its longitudinal section, fittings installed, cross-section of the pipe and amount of deposits.
The hose with the head are introduced to the pipeline through a launch manhole and after applying the pressure, it is moved forward by the jetting force of water. Water not only cleans the pipeline but also washes away the „muck” when pulling the hose back to the launch pit. The deposits are vacuumed from the pit with a pumping unit mounted on a sanitation truck.
The cleaning heads can have different shape and different mode of operation. Custom-making of heads to specific orders is not a problem.
When cleaning is complete, depending on technical options available, the efficiency can be checked using CCTV cameras or other methods approved by the Employer.
2. PART LINER rehabilitation
PART-Liner System is a universal and economic method of rehabilitating sewer networks of diameter from 150 to 1000 mm by using polyurethane sleeves 0.5 to 1.5 m long, i.e. the „short sleeve” system.
It is designed mostly for rehabilitation of specific points or places and rehabilitation of pipeline sections when the damage in the line does not exceed 30%. In those cases an rehabilitation sleeve of required length (even up to 15 meters) is made using overlapping section. The source material for production of the sleeves are is fiber glass ECR mats manufactured in France and Canada and polyurethane resins Harz 2000 manufactured in Germany. The components are of top quality and have EU certificates for use rehabilitating rainwater, sanitary, general and industrial wastewater networks.
The method is also successfully used for rehabilitation of new sewer lines, when minor flaws are found using CCTV control, such as:
- protruding seals,
- minor longitudinal and latitudinal cracks,
- leaks on connections: infiltrations, etc.
If the surface over the sewer is paved with asphalt, the repair is done non-invasively using a P-L system; it takes much less time than the traditional way and does not damage newly paved roadways.
