BS EN 12814-3:2014

What is BS EN 12814-3 - Tensile creep test for welded joints in thermoplastics about? 

BS EN 12814 is a European Standard series that discusses the testing of welded joints in thermoplastics semi-finished products. 

BS EN 12814-3 is the third part of the BS EN 12814 series that specifies the dimensions, the method of sampling, 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. 

Who is BS EN 12814-3 - Tensile creep test for welded joints in thermoplastics for? 

BS EN 12814-3 on tensile creep test of welded joints in thermoplastics is useful for: 

• Plastic industry 
• Thermoplastic polymer manufacturers 
• Quality control and testing authorities 
• Welders 
• Fabricators 
• Product specifiers 

Why should you use BS EN 12814-3 - Tensile creep test for welded joints in thermoplastics? 

Sometimes the life of a product is significantly shorter simply because of poor weld quality. Hence testing thermoplastic welding is important to identify and ensure the quality of the welded joints. 

The design of welded thermoplastics constructions under static load is based on the long-term creep rupture with behaviour, specifically the resistance to slow crack growth of the thermoplastics material and the welds. For design purposes, the relevant characteristic values for the welded joints are the “long-term tensile welding factors” to which BS EN 12814-3 provides the test method.  The long-term tensile welding factor(s), the crack behaviour and the appearance of the fracture surface provide information on the quality of the weld. 

The guidance in BS EN 12814-3 provides you with the dimensions and methods for sampling and preparing test specimens and the long-term welding factor requirements that must be adhered to during manufacturing to ensure the good quality welded joints and products. 

Thus, BS EN 12814-3 is your guide on demonstrating performance of welded joints in thermoplastics semi-finished products, thus ensuring failures arising from deformations are minimized. 

What’s changed since the last update? 

BS EN 12814-3:2014 supersedes BS EN 12814-3:2000 which is withdrawn. BS EN 12814-3:2014 includes some technical changes with respect to BS EN 12814-3:2000. These include: 

• Addition of a NOTE for an alternative test using a whole pipe welded sample (Clause 5) making reference to Annex B (informative), Whole pipe tensile creep rupture test 
• Addition of a NOTE for the sampling procedures (Clause 6) in case of socket joints with reference to Annex D (informative), Testing of socket joints