It is well know that during the casting of ship propellers small pores and tiny cracks may often arise within the material, which can lead to failure if not repaired.
Until now testing for defects has been carried out manually but it is difficult to achieve consistent and reproducible results with such manual processes.
To overcome this problem the Netherlands-based company MPR (Maritime Propeller Repairs) has, in collaboration with a specialised systems office, developed a new automated ultrasonic system for inspecting marine drive components, such as ship propellers.
A small lightweight measurement system is used with a mobile scanning device. The system includes all hardware and software components including instrument control, motion control, data acquisition, fast imaging of A-, B- and C-scans, evaluation and documentation tools.
The system is capable of recording large amounts of digitized ultrasonic testing data in real-time. On-site, the system currently scans an inspection area up to 900 x 450 mm and achieves speeds up to 200 millimetres per second. The mobile inspection system can be freely positioned on the propeller geometry; alternatively the scanning device can be attached by suction cups in vertical and horizontal positions.
The mobile inspection and scanning system is available for on-site inspections in foundries, at propeller manufacturers and in dry dock. The use of the system reduces the time for defect inspection and makes the interpretation of the results far easier and more reliable.