For a PVC-coated conduit system to achieve its longest possible service life and be most cost-effective, proper installation using the manufacturer’s recommendations is a must. Listed on this page are suggested installation methods to better protect PVC-coated conduit systems from corrosion, and techniques that will increase installer efficiency.
Installation Procedures
Clamping
When using a yoke-style vise, it is recommended that the jaw assembly be replaced with Jaws 3 vice adapters, which spread the clamping force over a larger area. For conduit diameters less than two inches in a chain-style vise, wrap the clamping area with emery cloth coarse side down, or secure the conduit with two pieces of angle iron. For conduit two inches in diameter or larger in a chain-style vise, use half-shell clamps to protect a large surface area while providing a strong grip. These methods will keep the conduit from spinning during cutting and threading.
Cutting
Use a roller cutter to cut PVC-coated conduit. When used properly, it will produce a square cut end and remove ¼” of the PVC coating to aid in the threading process. Use a reamer to remove any rough edges caused by cutting—this prevents any wire pulled through the conduit from being damaged. Conventional manual or power saws may also be used to cut conduit, but for conduit to be properly threaded, it is essential to ensure the cut is straight.
Threading
Always use a new die head to thread coated aluminum. Using the same die head to thread PVC coated aluminum and PVC coated rigid steel conduit is not recommended.
When using a power threader, ensure the threader dispenses clean threading lubricant. Prior to threading, gauge the length of the threads by placing the factory-applied thread protector on the cut end of the pipe and using a marker to mark the length. Hold a utility knife upside down on the mark and slowly press the foot pedal of the threader, causing the conduit to spin and a cut to be made around the circumference of the conduit. Then, make longitudinal cuts from the cut end to the mark. Thread the conduit to the mark.
When using a handheld threader, the conduit must be pencil-cut in order for the dye teeth to engage the conduit. Use the factory-applied thread protector to gauge the length of the threads by placing it on the cut end of the conduit and making a mark where it ends. Use a knife to cut around the circumference of the conduit at the mark, then make longitudinal cuts from the mark to the cut end of the conduit. Then, in the same manner as sharpening a pencil with a knife, cut away ¼” of the exterior coating at the cut end. Proceed with threading the conduit, using a pump oiler with good-quality thread cutting oil.
Once threading is complete, use a degreasing spray to clean the threads and the interior of the conduit. Never clean the conduit while it is still spinning in the power drive. Apply thread compound to all field cut threads to protect the bare metal from corrosion and ensure a completely sealed system.
Bending
PVC-coated conduit is available in a complete line of standard, special, and large-radius elbows ready for quick shipment. However, sometimes field bending may be necessary.
For hand bending ½” to ¾” size conduit, use equipment specifically designed to bend coated conduit. Or, if necessary, use the next larger size shoe to allow space for the PVC coating. A special PVC hickey is also available to make sharp bends, saddles, and offsets while reducing the potential of damage to the coating.
If a hydraulic bender is to be used, it is recommended to use shoes sized for coated conduit. If those are unavailable, conventional shoes can be machined out 0.006” to accommodate the coating thickness. Use rubbing alcohol to clean the inside of the shoe and the bending area of the conduit. Never use lubricant in the shoe or on the conduit. This could cause the conduit to slip above the centerline of the shoe, flattening the elbow.
Assembly
Special tools are available to aid in the installation of PVC-coated conduit systems.
PVC Touch-Up Compound can be used to repair nicks, cuts, and abrasions to the outer surface of a PVC-coated conduit. The touch-up compound can also be used as a sealant at access fitting openings and in wet locations.
The PVC Coating Repair Kit uses a custom formulated UL recognized two-part epoxy to repair damage in a small surface area that penetrates the coating and exposes the metal substrate.
When assembling parts of a PVC-coated system, Z-Wrenches can be used instead of standard adjustable pliers to spread the clamping force and allow for a secure grip without damaging the PVC coating. Strap wrenches can also be used to safely tighten conduit or couplings.
To efficiently speed up the assembly of smaller conduit sizes and fittings, use the Spin-It tool with a cordless impact driver. The Spin-It never touches the PVC coating and eliminates time wasted on repairing damage.
The unique Plasti-Socket can be used to speed up U-bolt and beam clamp installation while preventing encapsulated nuts from cracking. It creates a tight seal between the nut and the saddle for an efficient installation.
Use the innovative PVC-Coated Sealing Locknut to create a consistent seal over exposed conduit threads at points of connection, especially when a sleeve at the female thread is unavailable. The locknut’s simple design allows for easy installation and tightening over conduit threads at joints throughout the system, providing a sealed system that provides maximum protection and prevents costly and time-consuming corrosion damage.
The PVC-Coated SpeedCouple helps installers quickly and easily complete connections between PVC-coated rigid conduit and elbows, especially in tight space applications. The SpeedCouple’s internal swivel ring allows the connection to be made without having to turn the conduit or elbow, saving time by eliminating difficult maneuvers and money by eliminating the need to use costly unions in tight spaces.
In hazardous locations, all PVC-coated sealing fittings are equipped with the patented P5SA feature, which makes it simple to tell when the inspection plug is fully engaged. This gives additional assurance to both installers and inspectors that the plugs are engaged the first time, every time.