In 2019, TERLAN implemented an innovative spray-applied technology for the rehabilitation of water mains using COVERLAN composites.
We have applied the experience gained in the rehabilitation of drinking water pipelines conducted in many Polish cities to develop a new method for the rehabilitation of industrial infrastructure. In cooperation with Resimac TECH Ltd, we have developed and introduced a material called COVERLAN TECH to the Polish market.
We encourage you to learn more about this technology.
COVERLAN TECH coating is designed for trenchless rehabilitation of underground and above-ground pipes:
- for pressurized and non-pressurized cooling water in the power industry up to an operating water temperature of max. 50°C,
- for pressurized and non-pressurized non-potable raw water,
- for pressurized and non-pressurized technological and industrial fluid media transfer (for each application, an analysis of the applicability of resin material in contact with the flowing medium should be carried out),
- for non-pressurized and pressurized sanitary and rainwater sewers.
COVERLAN TECH is a solvent-resistant and abrasion-resistant hybrid epoxy coating specially designed for the rehabilitation of pressurized pipelines for process water, cooling water, non-potable water and sewage.
- Diameter range DN150 – DN1200 (higher diameters available on request)
- installation length: up to 170 m (up to 300 m for diameters higher than DN800)
- overcoming underground curves from 15° to 90° (depending on the diameter and design of the curves)
- tight-fitting coating maximises inner diameter while maintaining throughput
Technical specification:
Why is it worth using?
The innovation of COVERLAN technology translates into tangible benefits that should be taken into account when planning an investment. They concern environmental, financial, and functional aspects.
1
MINIMIZING THE AMOUNT OF EQUIPMENT ON THE CONSTRUCTION SITE
Direct impact on the size of the construction site and the scale of the ecosystem interference.
2
MINIMUM TECHNOLOGICAL TRENCH (max. 3 x 4 m)
Also minimal interference with the parent pipeline (2 m pipeline cut) what allows to maintain the traffic during the works and reduce the site restoration costs.
3
FULL COST OPTIMISATION
By flexible selection of coating thickness depending on the current condition of the pipeline.
4
THE TECHNOLOGY ALLOWS YOU TO ADAPT TO CHANGES IN THE DIAMETER AND NARROWING OF THE PIPELINE, SMOOTHLY OVERCOMES BENDS (up to 90°)
Cooling systems of power plants are notable for their large number of elbows and fittings, making the use of other methods, e.g. CIPP, very difficult.
5
NO CHANGE IN PIPELINE OPERATION AFTER REHABILITATION
The coating works together with the parent pipe; no additional tools are required to drill new connections or make process cuts for T-pieces or additional fittings.
6
IMPROVEMENT OF PIPE HYDRAULICS
The coating adheres tightly to the pipeline surface to maximize the cross-sectional area of the pipeline, and the smoothness of the coating makes it difficult for hard deposits to build up in the pipe.
7
NOT ONLY UNDERGROUND!
Thanks to the adhesion to the pipe surface and resistance to elongation of min. 4%, the technology creates a permanent pipe-coating bond, which also allows rehabilitation of the overhead pipelines.
8
THE COATING IS SELF-SUPPORTING.
This means that during its 50-year lifespan, it is resistant to the corrosion punctures that can occur when the pipe is corroding from the outside.
The COVERLAN composite centrifugal spray technology is based on the application of a coating of the appropriate thickness inside the pipe. Due to its adhesion to the parent pipeline and its flexibility, the material forms an integral pipe-coating composite.
The thickness of the coating is selected on a case-by-case basis depending on the diameter and condition of the pipeline in relation to its intended purpose. Two types of coatings are used:
- anti-corrosion – provides protection for the pipeline against corrosion,
- structural – reinforces the strength of the entire pipeline..
COVERLAN composite spray scheme
RIG
– spray
machine
guide
roller
starting
trench
shower
hose
pipeline
undergoing
renovation
shower
trolley
The COVERLAN pipeline rehabilitation process can be divided into 3 stages: preparation – spraying – inspection.
01
Preparation
This includes all the works required to preparation of the site and the starting chambers, including cutting into the pipeline itself. The pipeline surface must be clean and in good condition, free of rust, impregnants, foreign particles and any other materials. Therefore, the pipeline is cleaned and dried, after which all surface pitting is filled.
1.1
Cleaning
Once opened, the pipeline should be inspected by CCTV. Pre-cleaning involves the removal of tarnish and scale permanently adhering to the pipeline. This step can be skipped if pipeline conditions allow. The actual cleaning should be carried out using a high-pressure water jet. High-pressure cleaning prepares the pipeline for spraying. In hard-to-reach areas, manual cleaning is recommended.
1.2
Drying
After cleaning, the pipe must be thoroughly dried, as material cannot be applied to a wet surface. Adequate drying of the surface after cleaning determines the quality of the adhesion of the coating to the pipe. This can be achieved by leaving the pipeline open, allowing the pipe to dry naturally. This process can be assisted by using fans or manual drying. The basic method for ensuring that the pipeline has been properly dried is organoleptic verification, as well as verification using a CCTV camera.
1.3
Defect filling
If camera verification reveals issues with the structure of the pipeline, supportive measures should be used to fill any detected defects. Any cracks, holes and gaps present inside the pipeline should be repaired before the commencing of the spraying process.
02
Spraying
The material is sprayed by mixing it in a special RIG spraying machine, which then feeds the material via a spraying hose onto a spraying trolley, where it is automatically applied to the inside walls of the pipeline using centrifugal force.
COVERLAN should be applied in layers 1 mm to 2 mm thick in a single-pass mode. Multiple passes can be made when additional coating layers are required. The wall thickness is determined individually, depending on the prevailing pressure in the pipeline.
COVERLAN should not be applied to substrates with temperatures below 5.0°C.
03
Inspection
The entire spraying process is controlled by a qualified operator and recorded by the spraying machine using digital and analog methods. The surface of the COVERLAN coating forms a tight barrier protecting the pipeline against abrasion, corrosion, and the flowing medium.
