CPVC DUCTING
INSTALLATION
CPVC DUCTING
INSTALLATION
Joining Methods
Corzan® CPVC Duct can be easily assembled in the field using standard thermoplastic pipe joining techniques.
The most common methods involve thermal hot air welding or solvent cementing. Both of these methods provide reliable, cost-effective joints. Other methods of joining and fabricating Corzan CPVC Duct and system accessories include thermoforming, extrusion welding and hot-plate welding.
Solvent Cementing
Belled end duct, couplings, flanges and other socket style fittings can be joined using the solvent cementing process. This process involves the application of a primer and solvent cement to join system components.
Solvent cementing, or solvent welding, has been used successfully for more than 50 years in tough corrosive pressure applications. When properly conducted, this method provides a strong, homogenously joined area in which the mating surfaces are chemically fused together, producing a strong, leak tight seal when cured.
Detailed solvent cementing procedures are available and should be referenced for proper installation techniques.
Adequate surface-to-surface contact of the parts being joined is necessary for reliable solvent cemented joints. Generally, a minimum socket depth of 3 in. (all sizes) will provide sufficient joint strength for most systems.
Since duct dimensional tolerances can vary when compared to heavy wall pipe, the use of extra heavy bodied CPVC cement (such as IPS 3461 or equivalent) is recommended due to the cement’s excellent gap-filling properties. Care should be used when solvent cementing duct diameters 18 in. and larger to ensure tightness of fit of mating components. The solvent cementing method is not recommended for any type of end-joining.
Thermal Welding
The hot air welding technique utilizes clean hot air to preheat the duct material and CPVC welding rod, while pressure is applied to the weld area as the rod is guided along the mating surface areas. This joining method results in the surface molecules of the parts being joined to fuse together at the weld seam.
Only welding rod produced from Corzan CPVC material is recommended for this joining process to ensure the highest system integrity.
All welding should be conducted by personnel adequately trained in the art of hot air welding of thermoplastics. Detailed information concerning Corzan CPVC welding and fabrication is available.
Flanged Systems
For flanged systems, the general recommendations for flange fabrication are as follows: