A new molecularly oriented PVC pipe for pressure applications is designed to be lighter, have better impact resistance and increased tensile strength when compared to standard PVC.
The pipe, available from IPEX under the brand name Bionax™, is intended for use in water mains, sewer force mains, process piping and irrigation applications. It will be available in cast-iron outside diameters (CIOD): 4-inch through 12-inch Pressure Class 235 pipe; and iron pipe size (IPS): 4-inch through 12-inch Pressure Rated 160 pipe.
Molecularly oriented PVC (known as “PVCO”) was developed as an improvement to conventional PVC pipe. PVCO retains many of the same features as PVC, including resistance to corrosion and ease of installation.
Molecular orientation of PVC pipe is not a new concept. In fact, the process was developed in the early 1970s. However, PVCO pipe has been difficult to produce efficiently and in sufficiently high volumes. Thanks to recent innovations in the manufacturing process, IPEX is now able to offer the pipe as a stronger, tougher alternative to PVC.
How is molecular orientation achieved? PVC pipe is extruded at about half the diameter and twice the thickness of the finished PVCO pipe. (This unexpanded pipe is called “starting stock.”) Under controlled conditions during the extrusion process, the starting stock pipe is pulled over a mandrel, doubling the pipe’s diameter. This expansion process stretches the pipe in both the radial and longitudinal directions, reorienting the molecules to become biaxially oriented PVCO.
The PVCO pipe has almost double the tensile strength of conventional PVC, which yields larger internal diameters, lower flow velocities, and reduced pumping costs. It also has about triple the impact strength of PVC pipe. Reduced notch sensitivity results in a high resistance to cracking and splitting. If any pipe damage should occur, only local repairs would be required.
The biaxial orientation of the material allows the pipe to be more flexible than PVC and provides increased resistance to cyclic fatigue --about three times the resistance of PVC pipe.
The Bionax line carries the following Standards and Certifications:
- AWWA Standard C909 – PC 235 CIOD pipe
- ASTM Standard F1483 – PR 160 IPS OD pipe
- CSA Standard B137.3 – Bionax conforms to the performance requirements of the standard.
- Bionax is third-party certified to meet the AWWA C909 and ASTM F1483 standards.
