ISO/TC 138/SC 5 - General properties of pipes, fittings and valves of plastic materials and their accessories -- Test methods and basic specifications

This document specifies a test method for determining the resistance to slow crack growth of polyolefin pipes, expressed in terms of time to failure in a hydrostatic pressure test on a pipe with machined longitudinal notches in the outside surface. The test is applicable to pipes of wall thickness greater than 5 mm.

This document specifies two methods of testing for checking the leaktightness of assembled joints between mechanical fittings and plastic pressure pipes with diameters up to and including 63 mm. The test applies regardless of the design and material of the fitting used for jointing plastics pipe. This test method is not applicable to fusion-welded joints.

This document specifies a method for testing the leak tightness under negative pressure, angular deflection and deformation of assembled joints between elastomeric-sealing-ring-type sockets made of plastic or metal and plastic pressure pipes.

This document specifies a method for checking the ability of assembled uniaxial joints between fittings and plastic pressure pipes to withstand longitudinal tensile stresses. The test applies regardless of the design and material of the fitting used for jointing plastics pipe. This test method is not applicable to fusion-welded joints.

This document specifies a method for determining the tensile properties of pipes made of unplasticized poly(vinyl chloride) (PVC-U), oriented unplasticized poly(vinyl chloride) (PVC-O), chlorinated poly(vinyl chloride) (PVC-C) and high-impact poly(vinyl chloride) (PVC-HI, PVC-M or PVC-A), and in particular the following properties: — the stress at yield and stress at break; — the elongation at break. NOTE The general method of test for the determination of the tensile properties of thermoplastics pipes is given in ISO 6259‑1. This document also gives, for information purposes only, the corresponding basic specifications in Annexes A, B, C and D.

This document describes the phased array ultrasonic testing (PAUT) of polyethylene electrofusion (EF) socket joints used for the conveyance of fluids. This document provides a test whereby the presence of imperfections such as voids, wire dislocation, misalignment, pipe under-penetration, particulate contamination, cold fusion and lack of fusion in electrofusion socket joints can be detected. The technique is only applicable to polyethylene electrofusion socket fittings without a barrier to ultrasonic waves. This document also provides requirements for procedure qualification and guidance for personnel qualifications, which are essential for the application of this test method NOTE 1 At the time of publication, experience only exists on the use of PAUT for polyethylene (PE80 and PE100) electrofusion socket joint sizes between 90 mm and 710 mm (SDR 11 and 17)[7][8][9][10][11][12][13]. NOTE 2 Round robin testing has shown that PAUT is a viable method for enhancing the integrity assessment of electrofusion joints[16]. NOTE 3 This document does not apply to the detection of unscraped pipe. Such detection can be achieved by a simple visual inspection, provided mechanical scraping tools are employed.

This document describes the phased array ultrasonic testing (PAUT) of polyethylene butt fusion (BF) joints, including pipe-to-pipe, pipe-to-fitting and fitting-to-fitting joints, used for the conveyance of fluids. This document provides a test, whereby the presence of imperfections such as voids, inclusions, lack of fusions, misalignment and particulate contamination in the BF joints can be detected. The document is only applicable to polyethylene pipes and fittings without a barrier to ultrasonic waves. This document also provides requirements for procedure qualification and guidance for personnel qualifications, which are essential for the application of this test method. This document also covers the equipment, the preparation and performance of the test, the indication assessment and the reporting for polyethylene BF joints. The assessment of ultrasonic indications and acceptance criteria are not covered in this document. NOTE 1 At the present time, laboratory experiences exist on the use of PAUT for polyethylene BF joints and/or reference blocks of wall thickness between 8 mm to 100 mm[1] to [5]. Recently, field experience on BF joints in PE80 and PE100 materials has been reported[6]. NOTE 2 Round robin testing has shown that PAUT is a viable method for enhancing the integrity assessment of BF joints[7]. NOTE 3 PAUT techniques for cold fusion detection are known to be available. However further research, verification and experience are needed to transfer the technique into an ISO Standard. This document does not provide any information regarding the detection of cold fusions.

This document specifies a method for the preparation of test pieces assembled from polyethylene (PE) pipes or spigot-ended fittings and electrofusion fittings (e.g. socket fittings such as couplers, or saddles). The assembly criteria specified include parameters such as ambient temperature, fusion conditions, fitting and pipe dimensions, pipe configuration (coiled or straight pipe), taking into account the limiting service conditions specified by the relevant product standards. This document can apply to other shapes, e.g. re-rounded pipes, dependent on the manufacturer's instructions. NOTE For the purpose of this document, PE is understood to be PE, PE-RT or PE-X.

This document specifies test methods for the determination of the carbon black content of polyolefin compositions used in particular for the manufacture of pipes and fittings, and provides a basic specification for polyethylene pipes and fittings. This document applies equally to the material for manufacture and to any material taken from a pipe or fitting.

This document specifies the minimum values for expected strength as a function of time and temperature in the form of reference lines, for use in calculations on crosslinked polyethylene (PE-X) pipes and crosslinked medium density polyethylene (PE-MDX) pipes. NOTE 1 This document is applicable for pipes with the minimum level of crosslinking after production in accordance with Clause 4. NOTE 2 The density range for medium density polyethylene is 926 kg/m3 to 940 kg/m3 in accordance with ISO 17855-1:2014[2].

ISO 13761:2017 specifies a method for the derivation of pressure reduction factors to obtain the allowable operating pressure for operation of polyethylene (PE) pipeline systems at temperatures between 20 °C and 40 °C or 50 °C, dependent on the classification of the material used for manufacture.

ISO 9967:2016 specifies a method for determining the creep ratio of thermoplastics pipes having a circular cross-section.

ISO 9969:2016 specifies a test method for determining the ring stiffness of thermoplastics pipes having a circular cross section.

ISO 18489:2015 specifies a method to determine the resistance to slow crack growth (SCG) of polyethylene materials, pipes, and fittings. The test is applicable to samples taken from compression moulded sheet or extruded pipes and injection moulded fittings of suitable thickness. ISO 18489:2015 provides a method that is suitable for an accelerated fracture-mechanics characterization at ambient temperatures of 23 °C of different polyethylene grades, especially for PE 80 and PE 100 types for pipe applications. NOTE This test method could be adapted for other thermoplastics materials by developing the procedure using different test parameters.

ISO 18488:2015 specifies a method for the determination of the strain hardening modulus which is used as a measure for the resistance to slow crack growth of polyethylene. The strain hardening modulus is obtained from stress-strain curves on compression moulded samples. This International Standard describes how such measurement is performed and how the strain hardening modulus shall be determined from such a curve. Details of the required equipment, precision, and sample preparation for the generation of meaningful data are given. ISO 18488:2015 provides a method that is valid for all types of polyethylene, independent from the manufacturing technology, comonomer, catalyst type, that are used for pipes and fittings applications. NOTE This method could be developed for materials for other applications.

ISO 6259-3:2015 specifies a method of determining the tensile properties of polyolefin (polyethylene, cross-linked polyethylene, polypropylene, and polybutene) pipes, and the following properties: the stress at yield and the elongation at break.

ISO 3458:2015 specifies the method of test for checking the leak tightness of assembled joints between mechanical fittings and plastic pressure pipes. The test applies regardless of the design and material of the fitting used for jointing plastic pipe.

The ISO 6259 series specifies a method of determining the tensile properties of thermoplastics pipes, including the following properties: stress at yield, and elongation at break. ISO 6259-1:2015 is applicable to all types of thermoplastics pipe, regardless of their intended use.

ISO 17778:2015 specifies a method for determining the flow rate/pressure drop relationship of components for plastics piping systems when tested using air at 25 mbar.

ISO 13951:2015 specifies a method for testing the resistance to longitudinal tensile loading of uniaxial plastic pipe/pipe or pipe/fitting assemblies with electrofusion joints, butt fusion joints, or mechanical fittings (made of plastics or metals). For electrofusion joints and butt fusion joints, this test method is limited to nominal pipe diameters up to and including 250 mm.

ISO 3503:2015 specifies a method for checking the leak tightness under internal pressure of assembled joints between mechanical fittings and plastic pressure pipes when subjected to bending. It defines the calculation method for the average bending radius and how to perform this bending. Checking of the leak tightness under internal pressure is carried out in accordance with the method given in ISO 3458. This test method is not applicable to fusion-welded joints.

ISO 13845:2015 specifies a method for testing the leak tightness under internal pressure with angular deflection of assembled joints between elastomeric-sealing-ring-type sockets made of plastic or metal and plastic pressure pipes.

ISO 9080:2012 specifies a method for predicting the long-term hydrostatic strength of thermoplastics materials by statistical extrapolation. The method is applicable to all types of thermoplastics pipe at applicable temperatures. It was developed on the basis of test data from pipe systems.

ISO/TS 16479:2012 determines the slow cracking resistance of pipes and fittings using the Notched Ring Test (NRT) which is a method for determining the slow crack resistance of thermoplastics resins and compounds in pipe form and/or finished products (e.g. pipes and fittings) from which a ring specimen can be cut and notched. The test is performed under sustained constant loading in a test medium at a specified temperature and the time to the on-set of slow cracking is measured. This method applies to the rings from pipes or fittings having a wall thickness greater than 5 mm. ISO/TS 16479:2012 specifies the method of testing using notched ring specimens directly obtained from pipes or fittings.

ISO12230:2012 specifies minimum values for the expected strength as a function of time and temperature in the form of reference lines and tabulated data, for use in calculations on pipes made of polybutene-1 homopolymer (PB-H), and polybutene-1 random copolymer (PB-R). For the sake of simplicity the designation polybutene and the abbreviation PB are used throughout.

ISO 19893:2011 specifies a method for testing the resistance to temperature cycling of joints for piping systems with rigid or flexible thermoplastics pipes. It is applicable to thermoplastics piping systems intended to be used in hot and cold water pressure applications.

This International Standard specifies a method for testing the leaktightness under vacuum of joints for thermoplastics piping systems. It is applicable to piping systems based on thermoplastics pipes intended to be used in hot and cold water pressure applications.

ISO 19892:2011 specifies a method for testing the resistance of joints to pressure cycling. It is applicable to piping systems based on thermoplastics pipes intended to be used in hot and cold water applications.

ISO 23228:2011 specifies a method for the determination of the time-to-failure of thermoplastics resins and compounds for piping and fitting applications by the use of a plane strain grooved tensile specimen in a stress-rupture test. The grooved tensile specimen produces a biaxial state of stress on uni-axial loading, which is taken to be indicative of the stress conditions found in pressurized solid-wall plastics pipes. The ratio of the stress in the axial direction to the transverse direction approximates that for a pressurized end-capped solid-wall pipe specimen. It is intended that the data generated on these specimens be utilized to determine the stress-rupture (time-to-failure) resistance of moulding materials for pipes and fittings as well as experimental piping resins. This method is also applicable to stress-rupture evaluations of pipes which are difficult to test, e.g. larger diameter pipes, including their batch release tests. ISO 23228:2011 is not intended to replace the stress-rupture test of ISO 1167, which uses internally pressurized end-capped pipes.

ISO 10147:2011 specifies a method for the assessment of the degree of crosslinking in crosslinked polyethylene (PE-X) pipes and fittings by determination of the gel content by solvent extraction.

ISO 9311-2:2011 specifies a method for the determination of the shear strength of joints made with adhesives for thermoplastic piping systems.

ISO 21751:2011 specifies a strip-bend test method for the evaluation of ductility of the fusion joint interface of assemblies of pipe and electrofusion fittings and saddle fittings intended for the conveyance of fluids. It is applicable to polyolefin assemblies.

ISO 13956:2010 specifies a method for the evaluation of the ductility of the fusion joint interface of assemblies of polyethylene (PE) pipe and electrofusion or heated tool saddles, intended for the conveyance of fluids.

ISO 19899:2010 specifies a method to determine, for mechanically jointed polyolefin pipe and fitting assemblies in sizes of nominal outside diameter of less than or equal to 63 mm, the effect of component relaxation and creep on the resistance of the assembly to pipe pull out under the long-term application of a constant and longitudinally applied force.

ISO/TS 26873:2010 defines reference lines as the generic representation of the creep rupture properties of pipes made of thermoplastics material and gives procedures for drafting reference lines in a mathematical form.

ISO/TS 19911:2010 describes the individual elements of a technical file, specifying the characteristics of fittings with spigot ends for butt fusion or electrofusion assembling.

ISO 13967:2009 specifies a method of determining the ring stiffness of bends and branches made from thermoplastic material and for use with plastics pipes having a circular cross-section. The method can be used to determine the stiffness of bends, equal branches and unequal branches, provided the fitting allows a diametric deflection of at least 4 %.

ISO 12162:2009 establishes the classification of thermoplastics materials in pipe form and specifies the material designation. It also specifies a method for calculating the design stress. It is applicable to materials intended for pipes and fittings for pressure applications.

ISO 3213:2009 specifies the minimum values for expected strength as a function of time and temperature in the form of reference lines, for use in calculations on pipes made of: - polypropylene homopolymer (PP-H); - polypropylene block copolymer (PP-B) (also called heterophasic copolymer); - polypropylene random copolymer (PP-R); - polypropylene random copolymer (this material can be distinguished by DSC testing or another appropriate method to indicate a second melting peak) with a modified crystallinity (PP-RCT).

ISO 11414:2009 specifies a method for preparing butt-fusion-jointed test piece assemblies between polyethylene (PE) pipes and spigot-ended fittings. ISO 11414:2009 specifies the assembly parameters involved, such as the ambient temperature, joint geometry and fusion parameters, taking into account the service condition limits specified in the relevant product standards, as well as the type of pipe to be used. ISO 11414:2009 is intended to enable the effect of site assembly variables on joint performance to be determined. The fusion-jointing procedures and parameters used in the field can differ from those in ISO 11414:2009, depending on the manufacturer's written procedures and/or local standards.

ISO 24033:2009 specifies minimum values for expected strength as a function of time and temperature in the form of reference lines, for use in calculations on pipes made of: polyethylene of raised temperature resistance (PE-RT) type I; and PE-RT type II.

ISO 13968:2008 specifies a method for testing the ring flexibility of a thermoplastics pipe having a circular cross-section. The method enables determination of the deflection, and necessary force, at which physical damage, if any, occurs within the specified diametric deflection.

ISO 13477:2008 specifies a small-scale (S4) test method for determining the arrest or propagation of a crack initiated in a thermoplastics pipe at a specified temperature and internal pressure. ISO 13477:2008 is applicable to the assessment of the performance of thermoplastics pipes intended for the supply of gases or liquids. In the latter case, air can also be present in the pipe.

ISO 18373-2:2008 specifies a method for the determination of the enthalpy of fusion of crystallites in rigid PVC pipe samples. The method is based on the measurement of the thermal history using differential scanning calorimetry (DSC) and is suitable for all types of rigid PVC pipes.

ISO 1167-4:2007 specifies the procedure for the preparation of both end‑load‑bearing and non‑end‑load‑bearing assemblies, for the determination of their resistance to internal hydrostatic pressure according to ISO 1167-1.

ISO 1167-3:2007 specifies the procedure for the preparation of components, i.e. fittings and valve bodies, for the determination of their resistance to internal hydrostatic pressure according to ISO 1167-1.

ISO 13478:2007 specifies a full-scale test (FST) method for determining the arrest or propagation of a crack initiated in a thermoplastics pipe at a specified temperature and internal pressure. The method is also suitable for the determination of defined critical pressure, critical stress and critical temperature parameters. It is applicable to the assessment of the performance of thermoplastics pipes intended for the supply of gases or liquids. In the latter case, air could also be present in the pipe.