How to choose the right pipe lining resin? What are the different types of resins for lining and their specificities?

Pipe lining, an effective repair method for sanitation, drinking water, and industrial effluent networks, avoids complete pipe replacement. This technique involves inserting a flexible sleeve impregnated with resin inside the damaged pipe, which hardens to form a new sturdy inner wall adhering to the existing walls. It is a practical solution to fix cracks, leaks, corrosion issues, or even the presence of asbestos, without the drawbacks of heavy construction work.

This guide explores choosing the ideal resin for your lining project. It covers the different available resins, their characteristics and applications, to help you make an informed decision on the most suitable, efficient, and durable resin for your needs.

The foundation of the choice: understanding pipe lining

To select the ideal resin for your pipe lining project, it is crucial to understand the fundamentals of this renovation technique, its benefits, and the key criteria to make the right choice.

The principle of lining

This method creates a new internal layer inside damaged pipes without requiring their full replacement. It uses a flexible sleeve coated with resin that hardens by polymerization, thus adhering to the walls of the existing pipe.

Lining can be done by resin spraying via a robot, or by coating with a fiberglass sleeve, applicable to various networks (sanitation, drinking water, industrial effluents, etc.) and pipe materials (cast iron, concrete, PVC, steel, etc.).

Advantages of the method

Lining offers multiple advantages compared to traditional pipe replacement methods, notably it allows to:

• Repairing cracks, leaks, corrosion, or the presence of asbestos without resorting to demolition or excavation work.
• Minimizing costs, delays, and inconveniences related to the work.
• Increasing the performance and longevity of networks through better sealing, resistance, and flow of pipes.
• Preserving the environment by reducing material waste and soil pollution.

Essential selection criteria

Choosing the most appropriate resin for your project depends on several specific factors, including:

• The diameter, length, shape, and general condition of the pipe to be renovated.
• The type of network (drinking water, wastewater, industrial effluents, etc.) and the applicable standards.
• The properties of the resin (type, composition, viscosity, curing time, etc.) and its compatibility with the pipe material.
• The application conditions (temperature, humidity, accessibility, etc.) and the necessary equipment.

The different types of resins and their applications

There is a variety of resins used for pipe lining, each offering unique characteristics and applications. This article explores the four main types: epoxy, polyester, silicate, and vinylester resins.

Epoxy resins

Epoxy resins, thermosetting, harden following a chemical reaction between the resin and the hardener. They stand out for their superior adhesion, mechanical and chemical robustness, as well as their low viscosity. Ideal for drinking water pipes due to their compliance with health standards, they are also suitable for lining wastewater or industrial effluents thanks to their resistance to bio-aggressions and thermal variations.

Polyester Resins

Based on a chemical reaction between the resin and a catalyst, polyester resins are also thermosetting but at a lower cost than epoxies, though with limitations. With higher viscosity, their application is more challenging, and their lower chemical resistance makes them less suitable for industrial waters. Nevertheless, they are effective for wastewater pipelines, resisting biological attacks well.

Silicate Resins

Less common, silicate resins are mineral resins that harden through a reaction with a specific hardener. Their low viscosity simplifies their application, and their excellent chemical resistance makes them ideal for lining industrial conduits. Depending on the hardener used, they are suitable for both drinking water pipelines and wastewater or industrial water.

Vinylester Resins

Close to polyesters but offering better chemical and thermal resistance thanks to a reaction between the resin and a catalyst, vinylester resins are ideal for lining industrial effluents exposed to corrosive substances and high temperatures. They are also suitable for drinking water pipelines, meeting health standards.

Common points and major differences

These types of resins share several important characteristics:

• Used to reinforce pipelines, they create a new internal wall to repair damaged conduits.
• Solidification occurs through polymerization, a chemical reaction between the resin and another component (either a hardener or a catalyst).
• Offer an economical solution to repair rather than replace pipelines, thus minimizing costs, delays, and the inconveniences of construction work.
• Increase the performance and longevity of pipeline systems by improving their tightness, resistance, and flow capacity.

However, they differ according to several criteria:

• The type of network they serve (drinking water, wastewater, industrial effluents, etc.) and the specific standards to be met.
• Their viscosity, which directly impacts the ease of application and the final quality of the coating.
• Their chemical and thermal resistance, essential to withstand environmental constraints.
• The cost, which varies depending on the quality and specific performance of the resin.

Choosing the Ideal Resin for Your Project

After exploring the different types of resins and their uses, it is crucial to choose the one that best suits your pipeline renovation project. This decision involves considering several factors, such as the specifics of the pipeline concerned, the application conditions, the necessary preparation, and of course, the desired budget and durability.

Pipe Specifics

It is essential to know the details of the pipe to be rehabilitated: its diameter, length, shape, as well as its current condition. This information determines the choice of liner (fiberglass or polyester), the amount of resin required, and the application method. The composition of the pipe (cast iron, concrete, PVC, steel, etc.) must also be compatible with the resin to avoid any risk of degradation.

Application Conditions

The application context is another determining criterion. The type of network (drinking water, wastewater, etc.) as well as specific standards guide the choice towards suitable resins, such as epoxy resins for lining drinking water pipes. Climatic conditions and external aggressions (chemical, thermal, mechanical) also influence the selection in terms of resin resistance and curing.

Preparation and Application Constraints

The success of the application depends on the accessibility of the pipe, the possibility of shutting it down, and its cleanliness. Equipment requirements, project duration, and complexity must also be considered. The viscosity of the resin has a direct impact on the application; a resin that is too fluid can run, while a thick resin can be difficult to spread properly.

Cost and Durability

The budget and expectations in terms of renovation lifespan guide the final choice of resin. High-quality resins, such as epoxy or vinylester, although more expensive, ensure better long-term performance. Conversely, polyester resins, which are more economical, may offer lower resistance. It is crucial to find the right balance between cost and quality to best meet your needs.

Conclusion

This article has guided you in choosing the ideal resin for your pipe lining project, explaining how it works, its benefits, as well as the selection criteria for this network renovation method.

You have explored the different types of resins available and their specific uses. You have also learned how to assess the properties of the pipe in question, the environment where it is located, the preparation steps, implementation challenges, and the financial and durability aspects of the chosen resin.

Armed with this knowledge, it is time to take action. Call on a qualified and experienced specialist who can guide and support you in carrying out your pipe lining project.