Detailed analysis of pipeline failures

How to find out the causes of component failure? For us, the answer is simple – carry out a material analysis!

In our laboratory, we perform analyzes of failures of various elements, including pipelines or parts of machines and devices. We approach each case individually, selecting tests in such a way as to enable us to reach the source of the problem and propose further actions to the client to prevent the occurrence of undesirable events in the future.

We offered a customer who encountered a problem with a failure of cast iron pipelines, which led us to find out the cause of the problem. First, we performed fractographic examination of damage using stereoscopic and digital microscopy, thanks to which we determined the type and nature of the breakthrough. The above observations allowed us to select samples for further microscopic examination using light microscopy.

The aim of these studies was to identify the microstructure, type of material, its quality and degree of degradation. During microscopic tests, we additionally carried out the classification of the graphite microstructure in cast iron on the basis of a comparative visual analysis, in accordance with the PN-EN ISO 945-1 standard. It is worth noting that individual types of material are determined mainly by mechanical properties, therefore, in accordance with the relevant standards for the material used, we also performed hardness measurements and a static tensile test.

As a result of the analysis of individual results, we observed the loss of strength properties of the material as a result of long-term use and the presence in the microstructure of cast iron, an extensive mesh of triple phosphorus eutectic, the so-called steadite, which made the material more susceptible to brittle fractures. We presented a detailed analysis and interpretation of the results to the client in the test report.

Brittle fracture in the gray cast iron section of the pipeline

Gray cast iron microstructure with pearlitic matrix. Digested condition

An example of a site subjected to the classification of graphite microstructure in gray cast iron. Undigested condition

Gray cast iron microstructure with pearlitic matrix with phosphoric eutectic. Digested condition