EN 12814-6:2026

• Abstract:

  This document specifies the dimensions, the method of sampling and the preparation of the test specimens, also the conditions for performing the low temperature tensile test perpendicular to the weld in order to determine the low temperature tensile welding factor.; A low temperature 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 low temperature tensile welding factor and the appearance of the fracture surface provide a guide regarding the ductility of the joint and the quality of the work.; This document is applicable to co-axial or co-planar welded assemblies made from thermoplastics materials filled or unfilled, but not reinforced, irrespective of the welding process used.; This document does not apply to co-axial welded assemblies of an external diameter less than 20 mm.

• Status: Published
• Publication Date: 15-Sep-2026
• ICS: 25.160.40 - Welded joints and welds
• Technical Committee: CEN/TC 249 - Plastics
• Drafting Committee: CEN/TC 249/WG 16 - Welding of thermoplastics
• Current Stage: 6060 - Definitive text made available (DAV) - Publishing
• Start Date: 16-Sep-2026
• Due Date: 09-Nov-2026
• Completion Date: 16-Sep-2026
• Ref Project: SIST EN 12814-6:2026 - Testing of welded joints of thermoplastics semi-finished products - Part 6: Low temperature tensile test

• Replaces: EN 12814-6:2000 - Testing of welded joints of thermoplastics semi-finished products - Part 6: Low temperature tensile test
• Effective Date: 07-Aug-2024
• Referred By: EN 12814-8:2021 - Testing of welded joints of thermoplastics semi-finished products - Part 8: Requirements
• Effective Date: 17-Sep-2026
• Referred By: EN 12814-8:2001 - Testing of welded joints of thermoplastics semi-finished products - Part 8: Requirements
• Effective Date: 17-Sep-2026
• Referred By: EN 12814-8:2024 - Testing of welded joints of thermoplastics semi-finished products - Part 8: Requirements
• Effective Date: 17-Sep-2026
• Referred By: EN 14879-4:2007 - Organic coating systems and linings for protection of industrial apparatus and plants against corrosion caused by aggressive media - Part 4: Linings on metallic components
• Effective Date: 17-Sep-2026

EN 12814-6:2026 is a CEN European Standard for the low temperature tensile test on welded joints of thermoplastics semi-finished products. It specifies how to sample, prepare and test welded and unwelded specimens perpendicular to the weld so the low temperature tensile welding factor can be determined. It applies to co-axial or co-planar welded assemblies made from filled or unfilled, non-reinforced thermoplastics, with a diameter limit for small co-axial assemblies.

What does EN 12814-6:2026 specify?

EN 12814-6:2026 specifies the test specimen dimensions, sampling method, specimen preparation and test conditions for a low temperature tensile test performed across the weld. The document is organized into clauses on scope, references, symbols, test principle, sampling, specimen dimensions, cutting, mechanical testing, equipment, calculation and reporting, plus an informative annex with recommended test settings.

The standard is intended for assessing welded assemblies in combination with other checks such as bend, tensile creep and macro examination. In practice, it is used to judge joint ductility and the quality of the welding work from the welding factor and the fracture surface.

What are the key requirements of EN 12814-6:2026?

EN 12814-6:2026 requires a low temperature tensile test to be carried out perpendicular to the weld until brittle fracture occurs. The welded and unwelded specimens used for comparison must come from the same test piece so the result reflects the weld rather than material variation.

Sampling and specimen preparation

Clause 5 requires welded and unwelded specimens to be cut from the same test piece, at least eight hours after welding, and marked so their original position can be traced. No heat treatment or mechanical straightening is allowed, which matters because those actions could change the weld area before testing.

Clause 6 and Figure 1 set the specimen geometry. Tables 1 and 2 give the dimensions for co-axial assemblies and plates, and the bead is kept or removed depending on how the product is used in service. This ensures the test piece matches the actual joint condition the user cares about.

Cutting and examination

Clause 7 requires parallel-sided specimens and minimization of heating during cutting. Cutting must not create notches, and the weld must then be visually examined in accordance with EN 13100-1 and recorded. That makes the test traceable and helps separate cutting damage from weld defects.

Test conditions and equipment

Clause 8 requires conditioning at the test temperature in line with EN ISO 291, with the test then run at the same temperature and with temperature variation within ± 5 °C. At least five welded and five unwelded specimens are tested at the same temperature and speed, and if a specimen yields, the whole set from that test piece is repeated at lower temperature and/or higher speed to obtain brittle fracture behavior.

Clause 9 requires test equipment that complies with ISO 5893. Annex A gives recommended test speeds and maximum test temperatures for some materials, which helps laboratories select conditions that are more likely to produce a meaningful brittle-fracture result.

Calculation and reporting

Clause 10 requires the low temperature tensile welding factor to be calculated from the mean fracture stresses of the welded and unwelded specimens. At least ten specimens in total are used, and specimens are not ignored unless failure occurs in the clamps. The fracture type and the appearance of the fracture surface must also be assessed and recorded.

Clause 11 defines the test report content. In practice, the report captures the specimen identification, dimensions, test temperature, speed, measured forces, calculated stresses, the welding factor, deviations, unusual observations and the laboratory identification.

What terms does EN 12814-6:2026 define?

EN 12814-6:2026 uses symbols and abbreviated terms for the specimen dimensions, test forces, stresses and calculated result.

• Low temperature tensile welding factor (f) - the calculated ratio used to compare the welded specimen result with the unwelded specimen result.
• Fw - the force value used for welded test specimens in the calculation of f.
• Fr - the force value used for unwelded test specimens in the calculation of f.
• σw - the fracture stress for each welded test specimen used in the calculation of f.
• σr - the fracture stress for each unwelded test specimen used in the calculation of f.
• De - the external diameter of the co-axial assembly.
• a - the minimum measured thickness of the test specimen within the waisted section.
• b - the minimum width of the test specimen within the waisted section.

Who uses EN 12814-6:2026?

EN 12814-6:2026 is used by laboratories, weld testers, manufacturers and quality personnel working with thermoplastics welded assemblies. It is relevant for acceptance testing, weld procedure assessment, quality control and failure analysis where a low temperature tensile result is needed. Buyers and inspectors can also use it to specify how welded joints are to be tested and reported.

What changed in EN 12814-6:2026 from the previous edition?

EN 12814-6:2026 supersedes EN 12814-6:2000. The foreword states one technical change: if one test specimen yields, all specimens from both the welded and unwelded test pieces may be tested at a temperature and speed that produce brittle fracture, not just one specimen.

Which standards are used with EN 12814-6:2026?

EN 12814-6:2026 refers to these standards for supporting conditions and methods:

• EN ISO 291 - standard atmospheres for conditioning and testing plastics specimens.
• EN 13100-1 - visual examination of welded joints of thermoplastics semi-finished products.
• ISO 5893 - requirements for tensile, flexural and compression test equipment with constant rate of traverse.

What does the EN 12814-6:2026 document contain?

EN 12814-6:2026 contains a specimen figure, two dimension tables for co-axial assemblies and plates, and a calculation section for the welding factor. It also includes the procedure for cutting, conditioning and testing specimens, and a report checklist covering identification, test conditions, forces, stresses and fracture appearance. Annex A provides recommended test speeds and maximum test temperatures for selected thermoplastics materials.

SLOVENSKI STANDARD
01-november-2026
Preskus zvarjenih spojev plastomernih polizdelkov - 6. del: Trgalni preskus pri
nizki temperaturi
Testing of welded joints of thermoplastics semi-finished products - Part 6: Low
temperature tensile test
Prüfen von Schweißverbindungen aus thermoplastischen Kunststoffen - Teil 6:
Zugversuch bei tiefen Temperaturen
Essais des assemblages soudés sur produits semi-finis en thermoplastiques - Partie 6 :
Essai de traction à basse température
Ta slovenski standard je istoveten z: EN 12814-6:2026
ICS:
25.160.40 Varjeni spoji in vari Welded joints and welds
83.080.01 Polimerni materiali na Plastics in general
splošno
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EN 12814-6
EUROPEAN STANDARD
NORME EUROPÉENNE
September 2026
EUROPÄISCHE NORM
ICS 25.160.40 Supersedes EN 12814-6:2000
English Version
Testing of welded joints of thermoplastics semi-finished
products - Part 6: Low temperature tensile test
Essais des assemblages soudés sur produits semi-finis Prüfen von Schweißverbindungen aus
en thermoplastiques - Partie 6 : Essai de traction à thermoplastischen Kunststoffen - Teil 6: Zugversuch
basse température bei tiefen Temperaturen
This European Standard was approved by CEN on 26 July 2026.

CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this
European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references
concerning such national standards may be obtained on application to the CEN-CENELEC Management Centre or to any CEN
member.
This European Standard exists in three official versions (English, French, German). A version in any other language made by
translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC Management
Centre has the same status as the official versions.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,
Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway,
Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Türkiye and
United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2026 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN 12814-6:2026 E
worldwide for CEN national Members.

Contents Page
European foreword . 3
1 Scope . 4
2 Normative references . 4
3 Terms, definitions, symbols and abbreviated terms . 4
4 Principle of the test . 5
5 Sampling procedures . 5
6 Dimensions of test specimens . 6
7 Cutting of test specimens . 8
8 Mechanical testing. 8
9 Test equipment . 8
10 Determination of the low temperature tensile welding factor . 9
11 Test report . 10
Annex A (informative) Recommended test speeds and maximum test temperatures . 11

European foreword
This document (EN 12814-6:2026) has been prepared by Technical Committee CEN/TC 249 “Plastics”,
the secretariat of which is held by SIS.
This European Standard shall be given the status of a national standard, either by publication of an
identical text or by endorsement, at the latest by March 2027, and conflicting national standards shall be
withdrawn at the latest by March 2027.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CEN shall not be held responsible for identifying any or all such patent rights.
This document supersedes EN 12814-6:2000.
This document includes the following significant technical changes with respect to EN 12814-6:2000:
— it has been clarified that if one test specimen yields, all of the test specimens cut from both the welded
and unwelded test piece can be tested at a temperature/speed that generates brittle fracture, not just
one specimen.
Any feedback and questions on this document should be directed to the users’ national standards body.
A complete listing of these bodies can be found on the CEN website.
According to the CEN-CENELEC Internal Regulations, the national standards organisations of the
following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Croatia,
Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland,
Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Republic of North
Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Türkiye and the United
Kingdom.
1 Scope
This document specifies the dimensions, the method of sampling and the preparation of the test
specimens, also the conditions for performing the low temperature tensile test perpendicular to the weld
in order to determine the low temperature tensile welding factor.
A low temperature 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 low temperature tensile welding factor and the appearance of the fracture surface provide a guide
regarding the ductility of the joint and the quality of the work.
This document is applicable to co-axial or co-planar welded assemblies made from thermoplastics
materials filled or unfilled, but not reinforced, irrespective of the welding process used.
This document does not apply to co-axial welded assemblies of an external diameter less than 20 mm.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any amendments) applies.
EN ISO 291, Plastics -
...