Testing and quality

NDT - Non-destructive testing

Non-destructive testing (NDT) on steel pipes is a set of techniques used to assess the integrity, quality and structural properties of pipes without damaging them. This is crucial in sectors such as oil and gas, chemical processing, construction and infrastructure, where pipes play a critical role.

By applying an NDT, safety can be ensured; The timely detection of defects such as cracks, corrosion or wall thickness loss prevents failure. The examination ensures that pipes meet the correct specifications and standards and prevents unnecessary downtime and possible repair costs by identifying problems early.

NDT methods

There are differences the methods used to perform an NDT. The main methods performed at Herstaco are visual inspection, ultrasonic and magnetic examination of the welds made.

1. Visual inspection (VT)

A basic technique where the exterior and interior of pipes and welds are visually inspected for visible defects such as cracks, dents, or welding imperfections. The advantage is that it is fast, cheap and immediately feasible, however, no internal defects or invisible damage can be detected. Herstaco employs its own qualified (VT-w2) visual welding inspector.

2. Ultrasonic testing (UT)

High-frequency sound waves are sent through the pipe to detect internal defects such as cracks, delamination or variations in wall thickness. This examination is very accurate and suitable for measuring wall thickness and small internal defects. Herstaco uses external, certified researchers for this examination.

3. Magnetic testing (MT or MPI)

A magnetic field is created in the tube. Irregularities such as cracks disturb this field, which becomes visible using iron particles or magnetic powder. Magnetic examination is effective for detecting superficial and just below the surface defects. This examination is also carried out by an external, certified examiner.