Laboratory for weld testing

The laboratory of the Welding Institute carries out destructive and non-destructive testing of welds and materials in Ljubljana and Maribor and in the field. Testing is accredited by Slovenian Accreditation (LP-003) to SIST EN ISO/IEC 17025.

What tests do you carry out?

Destructive testing

Tensile tests, hardness, toughness, micro and macro examination, roughness measurements and chemical analysis of materials.

Non-destructive testing (NDT)

RT, UT, MT, PT, VT, leak testing, thickness measurement, ferrite and coating measurements.

Accreditation	LP-003, SIST EN ISO/IEC 17025 (Slovenian Accreditation)
Locations	Ljubljana, Ptujska ulica 19; Maribor, Zagrebška cesta 90
Fields	destructive testing, non-destructive testing (NDT), chemical analysis, electrical measurements
Testing	in the laboratory and in the field
Staff	NDT personnel are certified to EN ISO 9712 and PED; more than 20 certified full-time inspectors
Quality policy	laboratory quality policy (PDF, Slovenian)

Overview of tests and measurements

Mechanical tests: tensile tests, hardness and toughness measurements, micro and macro examination, roughness measurements.
Penetrant testing (PT): tests on a large number of materials, mainly as an independent body in the field.
Leak testing (LT): most often for leak testing after welding.
Chemical analysis: metallic materials in the laboratory or in the field (plasma, XRF).
Radiographic testing (RT): industrial radiography with X-ray equipment.
Magnetic particle testing (MT): the most suitable method for finding cracks in large ferromagnetic products.
Thickness measurements: after fabrication, wear or corrosion, including measurements of delamination of new materials.
Electrical measurements: various measurements, mainly on welding machines.
Ultrasonic testing (UT): all types of modern ultrasonic testing, mainly on welds.
Visual testing (VT): a quick and inexpensive method for finding surface defects, where we take part as an independent body.
Ferrite measurements: the ferrite content of stainless materials changes after welding, which we check with eddy currents.
Measurements of pressure equipment: to speed up the work of the notified body.

Frequently asked questions

Is the laboratory accredited?

Yes. The Welding Institute is accredited by Slovenian Accreditation under number LP-003 for testing to SIST EN ISO/IEC 17025.

Where do you carry out tests?

In the laboratories in Ljubljana and Maribor, and mainly NDT tests also in the field.

How do I order a test?

We carry out client requirements on prior order and in line with technical standards or other regulations and specifications. Send an enquiry or call the contact person.

Do you also test welders’ test pieces?

Yes, we examine the test pieces of welder certification in our own accredited laboratories.

Do you issue opinions on the condition of materials?

Yes, on the basis of testing we issue opinions and assessments of the condition of materials.

Last updated: 2 November 2026