API RP 15S:2006 pdf download

API RP 15S:2006 pdf download.Qualification of Spoolable Reinforced Plastic Line Pipe.
Pressure tests shall be conducted with potable waler as the pressurizing fluid. Addition ofadditivcs for boiling point suppression is acceptable if required. The qualification test temperature shall be selected by the manufacturer, and shall be greater than or equal to the design temperature in any application for which the product is employed. The prcfi.rcncc shall be for all tests to be conducted in a thermostat controlled water bath. For products with thcrmosct resin based outer layers, with no thermoplastic cover, regression data collected in air should be supplemented by proof of the longevity of the reinforced thermoset resin in an external wet environment. using a 1000 hr survival wst similar to that described in 5.1.3.
Test specimens may be taken either from straight pipe or from pipe that has been coiled. If straight pipe samples are employed. then the effect of reeling and unreeling on pipe performance during manufacture, installation and service can be proven with 1000 hour survival tests on two samples conditioned with 10 fully reversed cycles at the minimum storage bend radius. If this test is unsuccessful, or if the manufacturer prefers, pipe samples for full qualification shall be conditioned with 10 fully reversed cycles.
Where it is necessary to introduce discontinuities or joints of any type into the manufactured pipe. samples containing discontinuities shall either be employed in the full qualification procedure. or be treated as a product variant. Examples of discontinuities are joints in the reinforcing tape. PE liner butt welds are exempt from this, provided the appropriate procedures are followed to ensure consistent high weld quality, as described in 4.2.1, and that they arc subjected to the elevated temperature test.
Appropriate safety precautions should be observed during the pressure testing of plastic pipe. There are hazards on failure due to high-pressure fluid jets and the release of significant levels of strain energy.
5.1.2.2 Permissible Failure Modes
The manufacturer shall specify the principal mode (PM) of failure. For products reinforced with glass, carbon, ararnid or other non-metallic fibers, tensile (hoop) or mixed mode (hi-axial) failure the structural reinforcement shall be the only acceptable failure modes under hydrostatic pressure testing. These lead to loss of integrity by a combination of structural layer failure, localized leaking weeping, and or rupture of the liner and outer cover.
Any failure mode other than the PM invalidates the test. Any such failures shall be thoroughly investigated by the manufacturer to determine the cause, and the necessary steps shall be taken to prevent recurrence. Examples of non-permissible failure modes include failure of the liner (leading to pressurization of the structural layer). and failure involving an end fitting or coupler. especially the ejection of the pipe from the fitting or coupler.
5.1.2.3 Qualification Procedure
The pressure rating of the product family representative shall be determined by a series of stress rupture tests under constant pressure at the qualification test temperature. The procedure as described in ASThI I) 2992—Procedure B shall be used. At least IX failure points are required for this procedure. with not more than 2 samples below I 0() hours, at least three samples 1000 to 600t) hours, and at least one over 10,000 hours.
As illustrated in Figure 1. test data is used to determine the mean regression line of the long term hydrostatic pressure. LTHP. and its Lower Confidence Limit for the product family representative. LCLPFR. The LCL shall be taken as the value above which 97.5% of results can be expected to lie. The LCLPFR is obtained by extrapolating this confidence limit on the regression relationship until it meets the design life. In common with other composite pipe standards, a design life of 20 years should be assumed. unless otherwise requested by the purchaser. For transmission applications a 50 year life may also be quoted. Manufacturers may choose to express LCLs in terms of either hoop stress or pressure— stress units are typically more relevant to SCPs. while pressure units are more useful for RTP manufacturers. Figure I also shows the use of service factors for determining the maximum pressure rating and the maximum service pressure as described in 5.1.4 and 5.1.5.
A manufacturer may choose to carry out additional regression tests at a temperature lower than the qualification test temperature. Pressure ratings at temperatures between two test temperatures shall be based on a linear interpolation.