CPL Sump and Trench Liners

Plastic trench and sump liners are used in applications where coatings have not performed adequately or in applications where a primary and secondary containment system is required. Immersion service, where the trench and sump are constantly exposed to corrosive acids and caustics, are generally where trench and sump liners perform well. These materials are also classified as Concrete Protective Linings (CPL) that mechanically anchor into freshly poured concrete. The materials are available in a selection of resins including HDPE (high density polyethylene), polypropylene, PVDF, and E-CTFE (HALAR). When these materials are welded by certified welders, they offer years of maintenance-free, leak proof containment.

Frequently Asked CPL Questions:

Do I have to pour concrete? When using CPL materials, yes. Existing trench drains are usually saw cut on each side of the trench, to accommodate the new pour, rebar and reinforcement wire. By the time most trenches require retrofitting, that material should come out anyway, since it is contaminated from years of service and is exhibiting corrosion, or complete failure. Sumps are done differently, using the “overpour” method of installation. The lined sump area would be reduced by 3-4” off of each wall surface, to allow room for rebar and reinforcement wire.

Why not just use a drop-in liner? Drop in liners do not handle thermal cycling, which is a major factor in premature plastic liner failure. Additionally, due to the expansion ratio of plastics, they buckle during temperature rise and disrupting flows.

Can I monitor the liner performance with leak detection? Yes. Unlike coatings that bond chemically to the concrete, CPL mechanically bonds to concrete with anchors that are integrally molded to the plastic during the extrusion process. Leak detection can be visual or electrical monitoring. Dual wall CPL materials are available, as well as single wall systems.

Is there an advantage to using plastic trench drain and sump linings where seismic concerns exist? Due to the elongation properties of all CPL resins, the materials have 300-500% elongation before yield. This makes them ideal for geographic areas where seismic activity occurs.

How expensive are CPL materials? Each project is reviewed based on chemical concentrations, temperatures and other factors. CPL materials are more expensive than coatings, but they offer more value and performance than other options. We regularly replace coatings with CPL; coatings do not replace CPL trench and sump linings. We work with concrete contractors, and general contractors to assist you in keeping project costs to a minimum.

How is the product shipped? Trenches and small sumps can be prefabricated and pre-formed with block Styrofoam (no additional formwork is required). Larger sumps and tanks require field installation of CPL materials on the forms and field welding of seams and pipe penetrations.

How far will you go to install/weld CPL materials? Our crews work throughout the U.S, Central and South America. Please send us your inquiry, regardless of where you are.

How are welders certified? All Plastek Werks welders are certified by our company. Senior welders have more advanced welding certifications, such as those who have achieved DVS (German Welding Society) certification. All welders welding in a chemical or environmental application must be certified.