CEN/TC 249/WG 16 - Welding of thermoplastics

This document provides the requirements for the tests made on welded thermoplastics semi-finished products.
The selection of the appropriate test method(s) is made in accordance with the particular type and application of welded product.
The test results depend on the conditions of manufacture for the test specimen and on the test conditions. They can therefore only be related to the behaviour of the product or can only be used for designing a structure, if the test conditions can be related to the service conditions.

This document specifies the dimensions, the method of sampling, the preparation of the test specimens and the conditions for performing the tensile test with waisted test specimens in order to determine the tensile energy welding factor.
A tensile test with waisted specimens can be used in conjunction with other tests (e.g. bend, tensile, tensile creep, macro, etc.) to assess the performance of welded assemblies, made from thermoplastics materials.
The test is applicable to co-axial or co-planar heated tool butt welded assemblies made from thermoplastics materials filled or unfilled, but not reinforced. It is not applicable to tubular assemblies with a nominal outside diameter less than 90 mm.

This Technical Report identifies the quality related responsibilities and tasks included in the supervision of activities related to the welding of products and semi-finished products made of thermoplastic materials and provides guidelines to ensure the quality of the supervision.
The fundamental aspects of this Technical Report are the following:
- definition of tasks and responsibilities;
- definition of the required knowledge, skills and competence.
The plastic welding supervisor (PWS) should be employed by the organization involved in the welding activities. This Technical Report applies to all thermoplastic welding processes.

This document specifies quality levels for imperfections in thermoplastics welded joints that have cooled to ambient temperature and is applicable to material thickness above 2,0 mm.
Three quality levels are specified in order to permit application for a wide range of welded fabrication. They are designated by symbols B, C and D, where B is the most stringent. The quality levels refer to production quality and not to the fitness-for-purpose (see 3.2) of the manufactured product.
The quality level necessary are expected to be defined by the application standard or by the fabricator in conjunction with the user and/or other parties concerned. The level is expected to be prescribed before the start of production, preferably at the enquiry or order stage.
This document applies to the following thermoplastic materials in Table 1:
and to the following welding processes:
-   heated tool welding;
-   electrofusion socket welding;
-   hot gas welding using filler rod only;
-   extrusion welding;
-   solvent welding of pipes.

This document specifies the dimensions, the method of sampling, the preparation of the test specimens and the conditions for performing the tensile test in order to determine the short-term tensile welding factor.
A tensile test can be used in conjunction with other tests (e.g. bend, tensile creep, macro) to assess the performance of welded assemblies, made from thermoplastics materials.
The test is applicable to welded semi-finished products made from thermoplastics materials filled or unfilled, but not reinforced, irrespective of the welding process used.

This document specifies the method of testing the knowledge and skill of a welder who is required to carry out welds on thermoplastics in new constructions and repair work.
The skill examination of a welder is an essential condition for the assurance of the quality of the welding work.
The application of this document guarantees that the examination is carried out according to a uniform test procedure.
This document applies when the contractor or the authorities responsible for the application require it.
Gas and water utility network industries with alternative qualification programmes are excluded from this document.
This document applies to the following welding processes:
-   hot gas welding: round nozzle, speed, wedge;
-   extrusion welding;
-   heated tool welding: butt, saddle, socket, wedge;
-   electrofusion welding: socket, saddle;
-   solvent welding: socket.
This document applies to the welding of the following products:
-   sheet;
-   pipe (unreinforced, solid wall only);
-   fittings (unreinforced only);
-   lining membrane.
This document covers the welding of the following groups of materials:
a)   for sheets, pipes and fittings:
-   group 1: PVC (including all kinds of PVC-U, PVC-C) or ABS;
-   group 2: PP (including all kinds of PP);
-   group 3: PE (including all kinds of PE);
-   group 4: PVDF;
-   group 5: ECTFE or PFA or FEP;
b)   for lining membranes and flooring:
-   group 6: PVC-P;
-   group 7: PE (including all kinds of PE);
-   group 8: ECB;
-   group 9: PP;
c)   for pipes and fittings only:
-   group 10: PA-U 11 or PA-U 12.

This document specifies fundamental radiographic techniques with film, which enable repeatable results to be obtained economically.
This document applies to the X-ray radiographic examination of heated tool, electrofusion, extrusion and hot gas joints in plastics materials.
It applies to joints in solid wall pipes and plates with a range of thicknesses from 5 mm to 100 mm. It only applies to pipes containing air or other gases at the time of X-ray testing.
This document does not specify acceptance levels of the indications.

This document specifies a system for classifying imperfections that may be encountered in thermoplastic welded joints during manufacture and provides examples of imperfections for the following welding processes:
-   heated tool butt welding;
-   heated tool socket welding;
-   electrofusion socket welding;
-   hot gas welding;
-   extrusion welding;
-   solvent socket welding.
This document does not describe imperfections that may be generated during service or imperfections present before welding, which are due to poor preparation or assembly of components (e.g. fit up). The correct preparation and assembly of components (e.g. fit up) are described in the relevant welding procedure specification (WPS).
This document is also not concerned with the search for the possible influence of these imperfections on the behaviour of joints in relation to the different types of stress to which the latter may be subjected or on methods for preventing such imperfections.
This document can be used in conjunction with EN 16296 [1] to determine the acceptance of welds.
Only imperfections giving rise to discontinuities of materials or changes in shape are taken into consideration in this document, specifying their type, their shape and their positions. This classification can be used to determine the possible origin or causes of the imperfections.

This document specifies the dimensions, the method of sampling and the preparation of the test specimens, and also the conditions for performing the peel test perpendicular to the weld in order to determine the peel resistance and the failure behaviour.
A peel test can be used in conjunction with other tests (e.g. tensile creep, macroscopic examination...) to assess the performance of welded assemblies, made from thermoplastics materials.
Peel tests are applicable to overlap welded assemblies made from thermoplastics materials.
The T-peel test as defined in Clause 5 will be used only for assessing welded sheet assemblies. This test is not applicable to welded test pieces containing sheets of different nominal thickness.
The decohesion test as defined in Clause 6 will be used only for assessing electrofusion joints with nominal thickness of pipe/fitting greater than 10 mm.
For socket fusion and for electrofusion socket joints with nominal outside diameter less than or equal to 90 mm, a crush test will be used, as defined in Clause 7.
The crush test can also be used for electrofusion joints with outside diameters greater than 90 mm.
The crush test for electrofusion saddle joints will be performed in accordance with ISO 13955 [1].
NOTE   A decohesion test is also defined in ISO 13954 [2].
The tests defined in this standard are not intended to be used for assessment and/or qualification of thermoplastic fittings that already have their own requirements, e.g. polyethylene fittings according to EN 1555-3 [3] and EN 12201-3 [4].

This document specifies the dimensions, the method of sampling and the preparation of the test specimens, and also the conditions for performing the peel test perpendicular to the weld in order to determine the peel resistance and the failure behaviour.
A peel test can be used in conjunction with other tests (e.g. tensile creep, macroscopic examination...) to assess the performance of welded assemblies, made from thermoplastics materials.
Peel tests are applicable to overlap welded assemblies made from thermoplastics materials.
The T-peel test as defined in Clause 5 will be used only for assessing welded sheet assemblies. This test is not applicable to welded test pieces containing sheets of different nominal thickness.
The decohesion test as defined in Clause 6 will be used only for assessing electrofusion joints with nominal thickness of pipe/fitting greater than 10 mm.
For socket fusion and for electrofusion socket joints with nominal outside diameter less than or equal to 90 mm, a crush test will be used, as defined in Clause 7.
The crush test can also be used for electrofusion joints with outside diameters greater than 90 mm.
The crush test for electrofusion saddle joints will be performed in accordance with ISO 13955 [1].
NOTE   A decohesion test is also defined in ISO 13954 [2].
The tests defined in this standard are not intended to be used for assessment and/or qualification of thermoplastic fittings that already have their own requirements, e.g. polyethylene fittings according to EN 1555-3 [3] and EN 12201-3 [4].

This European standard covers the visual examination of welds in thermoplastic materials. It may also be applied to visual testing of the joint prior to and during the welding.

This Technical Specification provides guidance for the minimum content of welding procedure specifications for the following welding processes:
-   hot gas welding: round nozzle, high speed nozzle, wedge;
-   extrusion welding;
-   heated tool welding: butt, socket, wedge;
-   solvent welding: socket;
-   electrofusion welding: socket, saddle.
This Technical Specification applies to the welding of the following products and semi-finished products made of thermoplastic materials:
-   sheet;
-   pipe;
-   fittings;
-   lining membrane.

This European Standard specifies the dimensions, the method of sampling and the preparation of the test specimens, and the conditions for performing the tensile creep test perpendicular to the weld in order to determine the long-term tensile welding factor.
A tensile creep test may be used in conjunction with other tests (e.g. bend test, tensile test, macrographic examination,...) to assess the performance of welded assemblies, made from thermoplastics materials.
The test is applicable to welded assemblies made from thermoplastics materials filled or unfilled such as tubes and fittings, sheets, plates and profiles, but not reinforced, irrespective of the welding process used.

This European Standard specifies the equipment and methods for the high voltage testing of butt or overlap welded joints in thermoplastic sheets for locating through-thickness defects only. It applies to new unused constructions only.

This document specifies the cutting and preparation of test specimens and the conditions for performing the macroscopic examination of the test specimens.
The test is applicable to welded assemblies made from thermoplastics materials filled or unfilled, using the following processes:
-   hot gas welding: round nozzle, high speed nozzle, wedge;
-   extrusion welding;
-   heated tool welding: butt, saddle, socket, wedge;
-   electrofusion welding: socket, saddle.

This document specifies the dimensions and the method for sampling and preparing test specimens, together with the conditions for carrying out the bend test.
The result of the test is also influenced by the deformation behaviour of the tested material, the kind of welding process and the geometry of the sample.
The test is applicable to plate and tube butt jointed assemblies made from thermoplastic materials filled or unfilled, but not reinforced, irrespective of the welding process used. It is not applicable to assemblies with a wall thickness < 3 mm.

This document provides the requirements for the tests made on welded thermoplastics semi-finished products.
The selection of the appropriate test method(s) is made in accordance with the particular type and application of welded product.
The test results depend on the conditions of manufacture for the test specimen and on the test conditions. They can therefore only be related to the behaviour of the product or can only be used for designing a structure, if the test conditions can be related to the service conditions.

This Technical Report identifies the quality related responsibilities and tasks included in the supervision of activities related to the welding of products and semi-finished products made of thermoplastic materials and provides guidelines to ensure the quality of the supervision.
The fundamental aspects of this Technical Report are the following:
- definition of tasks and responsibilities;
- definition of the required knowledge, skills and competence.
The plastic welding supervisor (PWS) should be employed by the organization involved in the welding activities. This Technical Report applies to all thermoplastic welding processes.

This European Standard provides quality levels for imperfections in thermoplastics welded joints. It applies to material thickness above 2,0 mm.
Three quality levels are given in order to permit application for a wide range of welded fabrication. They are designated by symbols B, C and D, where B is the most stringent. The quality levels refer to production quality and not to the fitness-for-purpose (see 3.2) of the manufactured product.
This European Standard applies to the following thermoplastic materials:
Table 1
Abbreviation   Material description
ABS   Acrylonitrile-butadiene-styrene plastic
ECTFE   Ethylene-chlorotrifluoroethylene copolymer
FEP   Fluorinated ethylene propylene
PB   Polybutylene
PE   Polyethylene
PFA   Perfluoroalkoxy
PP-B   Polypropylene block copolymer
PP-H   Polypropylene homopolymer
PP-R   Polypropylene random copolymer
PVC-C   Chlorinated polyvinyl chloride
PVC-U   Unplasticised polyvinyl chloride (rigid PVC)
PVDF   Polyvinylidene fluoride
and to the following welding processes:
- Heated tool welding;
- Electrofusion welding;
- Hot gas welding using filler rod only;
- Extrusion welding;
- Solvent welding of pipes.

This European Standard specifies the method of testing the knowledge and skill of a welder who is required to carry out welds on thermoplastics in new constructions and repair work.
The skill examination of a welder is an essential condition for the assurance of the quality of the welding work.
The application of this standard guarantees that the examination is carried out according to a uniform test procedure.
This European Standard applies when the contractor or the authorities responsible for the application require it.
Gas and water utility network industries with alternative qualification programmes are excluded from this standard.
This European Standard applies to the following welding processes:
- hot gas welding: round nozzle, high speed nozzle, wedge;
- extrusion welding;
- heated tool welding: butt, saddle, socket, wedge;
- electrofusion welding: socket, saddle;
- solvent welding: socket.
This European Standard applies to the welding of the following products:
- sheet;
- pipe;
- fittings;
- lining membrane.
This European Standard covers the welding of the following groups of materials:
a)   for sheets, pipes and fittings:
1)   group 1: PVC (including all kinds of PVC-U, PVC-C), ABS;
2)   group 2: PP (including all kinds of PP);
3)   group 3: PE (including all kinds of PE);
4)   group 4: PVDF;
5)   group 5: ECTFE or PFA or FEP;
b)   for lining membranes:
1)   group 6: PVC-P;
2)   group 7: PE (including all kinds of PE);
3)   group 8: ECB;
4)   group 9: PP.