
Duraliner is a unique, patented technology for pipeline renewal resulting in a "stand alone" structural lining. In addition, Duraliner provides an equivalent design-life of new PVC pipelines, thus qualifying the rehabilitated pipelines to be capitalized as new assets under the rules of GASB Statement 34.
The Duraliner system utilizes starting stock of 100% PVC pressure pipe that conforms to cell classification 12454 as defined in ASTM D1784, meets ANSI/AWWA C900 or ANSI/AWWA C905 and NSF 61 Standards for Drinking Water System Components/Health Effects. The outside diameter (OD) of the starting stock is smaller than the inside diameter (ID) of the host pipe. The starting stock pipe sections are fused together and inserted into the entire length of the host pipe. Heat and pressure are applied to expand the pipe tightly against the interior walls of the host pipe - a computer control system is used to manage the process and equipment parameters.
As the starting stock is expanded, the longitudinal molecular structure of the polyvinyl chloride (PVC) is reoriented to a circumferential direction. This new molecular orientation increases physical and mechanical properties of the Duraliner tensile strength. Consequently, the hydrostatic design basis (HDB) is substantially increased from 4,000 psi. Extensive third party testing and research have been conducted to develop the exact nature of the relationship between HDB and the wall thickness ratio of the starting stock wall to the finished expanded pipe. Duraliner pressure ratings can then be calculated using the conventional AWWA formulas with the enhanced HDB.
Duraliner ends can be expanded to a variety of standard sizes using a sizing sleeve. The most common applications have Duraliner expanded to ductile iron (DI) outside diameters (OD), making standard PVC gasketed fittings compatible. Ductile iron mechanical joint fittings and ductile iron push on type fittings can be installed directly onto Duraliner, using the standard M.J. gasket made for cast iron or ductile iron pipe. Any joint restraint devices that are commonly used with standard PVC can be used with Duraliner.
Duraliner is one of the easiest and safest pipes to tap. Duraliner may be tapped with the same tapping saddles used on conventional PVC. The service saddles used should provide full support around the circumference of the pipe and a bearing area of sufficient width along the axis of the pipe. When tapping Duraliner one should refer to the Uni-Bell PVC Pipe Association's guidance for tapping PVC.
Applications for this technology cover every aspect of piping installations including both pressure and non-pressure situations in the water, sewer, industrial and telecommunications industries.
Duraliner is the structural stand-alone water line replacement system for pressure pipe applications from 4" to 16" in diameter. The standard product is designed to deliver a standard operating pressure (the US water industry standard) with a 2.0 safety factor.
Duraliner products offer numerous benefits at or below the cost of alternative methods: