Root cause investigation

Thanks to large experience and a well equipped material laboratory CSI Nordic can solv different material problems. The methodology is built on a systematic investigation approach where different analyse techniques are used to localize the source of the problem. A central point in the investigastion work is the communication with the customer from project start with problem description and background information and continuous status updates.

Systematic failure investigation

CSI Nordic performs systematic investigations on accidents (failure, fractures) and industrial damages. The work consists of gathering information on the actions that can be connected with the accident. Important information can be design drawings, operation data and maintenance routines at the company. It is important that CSI Nordic can be on site immediately to secure that no “evidence” is missing at the “crime scene”. The damage is studied in detail by visual control, measurement and photo documentation. Quite often pieces are cut out from samples and studied in detail in CSI Nordics material laboratory. Information on microscopic level of a fracture surface can in many cases explain the history behind how the damage occured. The work can be compared to building a puzzle where each piece layd down makes the image of how the damage occured getting more and more clear. Unfortunately not always all puzzle pieces are found but it is important to make an assessment on which factors most likely have caused the damage. CSI Nordic has a large spectrum och deep knowledge on material, production methods, impact of operation, degradation, remaining lifetime, function and a profound knowledge of material analysis.

Investigation

For failure and damage analysis often following methods are used:

  • Visuel control, measurement and foto documentation
  • Review of drawings and operation protocols
  • Nondestructive testing of material condition and grade of degradation
  • Investigation of crack type and size and fracture surfaces
  • Evaluation and calculation of stress states during operation
  • Calculation of crack formation speed and critical crack size
  • Evaluation of operation temperature and environment

Sources for damage

  • Design error
  • Choice of material
  • Wrong chemical composition
  • Wrong structur
  • Inclusions and slags
  • Quality differences in material properties
  • Welding mistakes
  • Small scratches or break necks in critical parts
  • Not according to design
  • Deviating process parameters
  • Vibration
  • Fatigue load
  • Corrosion
  • Wear (wear, friction, lubrication)