Assessment of the technical possibility of the Ship Loader modernization (productivity increasing)

Example from the defect list, which was prepared during the structural inspection.

Extra tests performed:

  • Ultrasonic thickness measurement to evaluate degree of corrosion;
  • Vibration-based diagnostics of mechanism elements (gearbox, motor etc.), which allows to diagnose their technical conditions without taking them to pieces;
  • structure inspection using non-destructive testing (visual, ultrasound and magnetic tests);

The inspection revealed defects in steel structure, mechanisms and safety devices. Without repair of the defects the further operation of the machine is impossible. The steps to be taken for restoring the machinery to service have been defined.


The Ship Loader structure strength check for the case of increased productivity

Structural analysis of the Ship Unloader structure showed that most of the structure main elements met the strength criterion for the case of increased productivity.

We have also determined structure elements, which are to be reinforced during repairs to avoid collapsing of the entire steel structure.


Ship Loader maximal wheel load determination for the case of improved productivity

Maximum wheel load is limited by maximum quay load. Due to lack of data about design wheel load, the value was determined experimentally, using strain-gauging measurement. Then based on the data obtained from measurements the wheel loads for the case increased productivity were calculated.

It was proved that the wheel load in the case of the increased productivity is lower the maximum quay load. In other words, operation of the Ship Loader in the case of the increased productivity will not cause damage to the quay.

This is an original approach developed by the laboratory engineers.

CONCLUSIONS
  1. During the structural inspection of the Ship Loader some critical defects have been found due to which further operation of the crane is not acceptable.
  2. Ship Unloader structure analysis showed that it was technically feasible to increase productivity of the machine in terms of its structure strength on the assumption of critical elements reinforcement.
  3. The residual life assessment shows elements for which the residual life is less than 5%. For further trouble free operating it was suggested to repair/reinforce the detected critical elements.
  4. Based on the obtained Ship Loader wheel load, it was found that the machine’s operation at increased capacity would not cause destruction of the quay, since the wheel load is lower than maximum permissible load for the quay.

So, it may be technically feasible to modernize the Ship Loader, following proper repair, reinforcement of its structure critical elements and repair/reinforcement of ones with short remaining life