Is Duraliner™ approved for drinking water?
Yes, Duraliner™ conforms to ANSI/NSF - 61 - Drinking Water System Components - Health Effects. Duraliner™ has been tested by NSF and certifications are listed on the NSF website under Pipe and Related Products.
What types of pipes can I reline with Duraliner™?
In reality, any type of pipe that is accessible can be relined with Duraliner™. Cast iron, ductile, concrete, welded steel, corrugated steel, asbestos cement and even wooden pipes can be relined with Duraliner™.
Does Duraliner™ rely on the structural integrity of the host pipe to resist internal pressures?
No. Duraliner™ is a stand-alone structural piping system. Duraliner™ provides normal operating pressure with a 2:1 safety factor without relying on the condition of the host pipe.
Will I save any money by installing Duraliner™?
Yes. We all know that job costs vary greatly depending on the specific conditions associated with each project, but on average, installing Duraliner™ will save you 30% to 50% over traditional dig & replace methods, especially in congested urban areas.
What effect does Duraliner™ have on friction loss?
Since the interior surface of Duraliner™ is very smooth, less power will be required to transmit fluids in Duraliner™ compared with most other piping systems. Furthermore, the excellent corrosion resistance of Duraliner™ means that the low friction loss characteristic will not change over time. Duraliner™ "C" value is consistent with PVC and is in the 150 range, this value is significantly better than the existing lines that Duraliner™ is installed in. Aged, corroded lines usually have a "C" value in the 80~100 range.
What is the life expectancy of Duraliner™?
PVC has an impressive record of long-term durability. When water utility managers and engineering firms were surveyed in a study sponsored by the American Water Works Association Research Foundation (AWWARF), they cited corrosion resistance, longevity and durability as their top reasons for choosing PVC piping. When these same water professionals were asked to rank PVC against other common types of pressure pipes for life expectancy, PVC ranked first. [Source: Moser, A.P., and Kellogg, Kenneth G., "Evaluation of Polyvinyl Chloride (PVC) Pipe Performance," AWWA Research Foundation, Denver, Colorado, 1994.] According to the Uni-Bell PVC Pipe Association, a properly designed and installed PVC pipe system (such as Duraliner™) should have a conservative service life of 100 years.
Is Duraliner™ resistant to corrosion?
Yes, Duraliner™ is PVC, which is not conductive so it is therefore immune to galvanic or electrolytic erosion. Since Duraliner™ is corrosion resistant, it can be utilized in acidic, alkaline, wet or dry conditions and protective coatings are not required.
Is Duraliner™ chemical resistant?
Yes, Duraliner™ is resistant to many chemicals; however each proposed industrial application should be evaluated separately before installation of Duraliner, or any other thermo-plastic.
Is Duraliner™ resistant to biological attack?
Yes, to date there are no documented reports on any fungi, bacteria, or termite attacks on any PVC piping system. In fact, because of its inertness, PVC piping is the preferred material in deionized and other high-purity water applications. See the report entitled "Resistance of Thermoplastic Piping Materials to Micro- and Macro- Biological Attack TR-11/2000" issued by the Plastics Pipe Institute located in our Technical Information section.
Does Duraliner™ have a low thermal conductivity?
Yes, Duraliner™ has the same conductance as PVC, which is low. This feature maintains more uniform temperatures when transporting fluids than in metal piping. In certain industrial applications, low thermal conductivity of the wall lined with Duraliner™ may eliminate or reduce the need for pipe insulation to control sweating.
Is Duraliner™ resistant to abrasion?
Yes, Duraliner™ provides excellent service in handling slurries such as fly ash, bottom ash, and other abrasive solutions. The material toughness and smooth inner-bore of Duraliner™ make it ideal for applications where abrasion-resistance is needed.
How will Duraliner™'s performance hold up long term?
Owing to the relative chemical inertness and the minimal effects of internal and external corrosion on Duraliner™, there is very little change in the physical characteristics of Duraliner™ over many years of use.
Can Duraliner™ be exposed to the sun?
Duraliner™ does not readily degrade when exposed to sunlight (ultraviolet radiation) due to the high level of UV inhibitors present in the material. Short-term exposure to sunlight, such as during installation, is not a problem for Duraliner™. Permanently exposed sections of Duraliner™ may be used in outdoor applications when the exposed Duraliner™ is painted with a light-colored water based acrylic or latex paint that is chemically compatible with PVC. When painted, the effects of UV exposure are significantly reduced.
In order to accurately quantify the effects of UV radiation on PVC pipe, the Uni-Bell PVC Pipe Association conducted a two-year study in the late 1970's at various outdoor locations in the United States and Canada. In this study, PVC pipe samples were placed on horizontal exposure racks and placed so that they received continual exposure to the sun. At various points throughout the study, tests to evaluate mechanical properties were performed on the portion of the pipes that received the maximum UV exposure.
The results of the study (published as UNI- TR-5, "The Effects of Ultraviolet Aging on PVC Pipe") indicate gradual decline in the pipe's impact strength. The lowest impact strength recorded after two years of exposure was 158 ft-lb, or 75% of the original ASTM value. Even this reduced value exceeds those of most alternate pipe products. These results indicate that no unusual handling problems should be expected from Duraliner™ even after long-term exposure to sunlight.
The study results also show that Modulus of Elasticity and Tensile Strength were virtually unaffected. The fact that these properties were unaffected signifies that structural integrity and pressure capacity remain unchanged. UV degradation does not continue after installation when exposure to UV radiation is terminated.
Can Duraliner™ withstand a vacuum? If so, what is the maximum vacuum that Duraliner™ can withstand?
Yes, Duraliner™ can withstand vacuum pressures. According to research conducted by Dr. R.K. Watkins at Utah State University, vacuum pressures cannot collapse an underground PVC pipe that is properly encased in a soil envelope (or a host pipe in the case of Duraliner™) and exposed to normal service temperatures. In fact, quick calculations show that even under conditions of elevated operating temperatures of 100 degrees F, the pressure required to collapse most PVC pipe is greater than atmospheric. In other words the pipe (and therefore Duraliner™) can withstand a complete vacuum. Vacuum pressures are generally not considered a favorable occurrence in water distribution systems of any pipe material. However, if the effects on the entire system are taken into consideration, Duraliner™ offers adequate strength and safety to withstand vacuum pressures.
Does Duraliner™ require extensive maintenance?
No. When properly designed and installed, Duraliner™ requires no maintenance because there is no rust, pitting, or scaling to contend with. The interior and exterior surfaces of Duraliner™ are not subject to galvanic corrosion or electrolysis. Duraliner™ is not generally affected by chemically aggressive environments.
What are the maximum internal temperature limitations of Duraliner™?
The maximum long term internal fluid temperature of Duraliner™ is 140 degrees F.
Can Duraliner™ negotiate bends?
Duraliner™ easily handles the normal sweeps and direction changes made by joint deflections in bell and spigot cast iron, ductile iron, RCP, etc. Depending on the Duraliner™ starting stock and the host pipe ID, some 11 ¼ degree and 22 ½ degree elbows have been successfully pulled through and lined.
Does the added wall thickness of Duraliner™ restrict the flow through the pipe?
No, although the ID (inside diameter) of the host pipe is slightly reduced, the smooth interior walls of the Duraliner™ reduce friction and maintain if not increase the flow capability within the lined pipe. This means that for the same head loss, more flow is possible, or for the flow less head losses will be generated.
Can Duraliner™ bridge holes, corrosion pits, intervals between pipes and open joints?
Yes, and as a structural stand-alone system, they have no bearing on the pressure rating, structural integrity or longevity of the new Duraliner™ system.
What is the maximum length of Duraliner™ installed between access pits?
That really depends on a number of factors such as how straight the existing host pipe is laid, the diameter of the host pipe and the wall thickness of the Duraliner™ starting stock (which is determined by the operating pressures of the system), and the capacity of the equipment available. To date the longest run in commercial service is in the 700 foot range. Duraliner™ expansion equipment as presently sized was intended for the "city block" length of about 500ft. In most projects, fitting location, pit access points, valve location, etc. are the limiting factors as to how long of a run can be expanded.
Are special fittings and valves needed to reconnect the system?
No. The Duraliner™ system is 100% compatible with conventional fittings and valves used every day by water companies throughout the United States. Standard MJ fittings with standard PVC restraints are used to connect together sections of Duraliner™ with valves, fittings, etc.