The primary function of a PVC-coated conduit system is to maximize the life of the electrical system contained within it and to prevent corrosion from sabotaging its structural integrity. This is achieved through a PVC coating properly adhered to the external surface of the conduit and fittings, preventing exposure to external environmental conditions that could result in corrosion of the steel or aluminum substrate.
Preventative Measures
A variety of solutions exist to prevent the occurrence of damage to PVC-coated conduit systems. Some manufacturers of factory-coated products offer free installation training and certification based on classroom instruction, hands-on instruction, and online tutorials. Through the utilization of proper tools and methods during the installation process the product will perform as designed by the manufacturer.
Disaster Strikes
However, damage is possible due to accidents – even with trained personnel. Bundles of heavy conduit can be dropped onto hard, pointed surfaces; construction equipment and tools can fall or run into a system. In these cases, a method of repair is inevitable. As a result, PVC-coated manufacturers have developed products to easily patch minor defects to the factory-applied coatings.
Damage Control
Perma-Cote currently offers a PVC Touchup Compound and Touchup Spray to repair minor damages to the surface of the PVC coating. However these compounds are not formulated nor are they intended to bond to the metal substrate when the damage penetrates the coating and exposes the metal substrate. For these cases, a PVC Coating Repair Kit was developed using a custom formulated UL recognized two part epoxy capable of bonding to both polyvinyl chlorides and steel or aluminum substrates.
The repair kit includes all tools needed to prepare a small surface prior to applying the epoxy patch. This includes an emory cloth to prepare the surface of the damaged area, mixing tools, cleaning cloths, an applicator tool, instruction sheet, and chemical information (SDS) for the compound. The PVC Coating Repair Kit uses a two-part epoxy cold weld system that provides strong, lasting repairs to metal and PVC. After mixing, it forms a permanent bond that can be shaped, tapped, filed, and sanded after curing. The PVC Coating Repair Kit epoxy sets in 6 minutes and cures in 3-4 hours (at 70⁰F) to a dark grey color that matches Perma-Cote’s PVC coating. This epoxy is a UL recognized performance material that has been tested for flame resistance according to UL’s HB Flammability test for safety assurance.
| Property | Rating |
|---|---|
| Flame Resistance | HB Rating – self-extinguishing |
| Tensile Strength | 3960 psi |
| Heat Resistance | 550⁰F – No change after cooling |
| Freeze Resistance | -67⁰F – No change after thawed |
| Hardness | 2H-4H pencil (ASTM D2240) |
| Adhesion | Pull Test – Pass |
| Conductivity | This material is an insulator |
Once the epoxy is completely cured, it is resistant to water, gasoline, and other petroleum products. It is important to note that the kit is only for use in the case of small repairs caused by unavoidable damage to PVC conduit systems. It should not be used to repair damaged areas with a surface area greater than 4 in2.
For additional information on the PVC Repair Kit and proper application, please see the below video.
