Deep Water Horizon Accident Helps In Forecasting Pipe Fractures

The deep water horizon accident commonly referred to as “Gulf oil accident” is an unforgettable incident in the history of oil drilling in high seas. The Gulf oil disaster occurred when methane gas suddenly erupted out of the pipe and engulfed whole oil drilling platform after which the oil rig sank to the bottom of ocean.

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MIT researchers found almost perfect match for their pipeline fracture simulation (bottom) and an image of the Deepwater Horizon's ruptured pipeline taken by an underwater remotely operated vehicle.

#-Link-Snipped-# tried to correctly simulate the whole process to avoid such future accidents. The team led by Tomasz Wierzbicki of MIT University is trying to predict the strength of pipes required in high shore applications. The physical and mathematical model prepared by the team simulates the actual fracture and bends occurred in pipes to a high degree of accuracy. Researchers have tallied their reconstruction with the images that a remotely operated robot had taken. The pictures suggest that the model closely resembles as that of the actual situation. The team which consisted of Wierzbicki and graduate students Kirki Kofiani and Evangelos Koutsolelos has presented their work at #-Link-Snipped-# this June.

In the method that was developed by Wierzbicki, he sprayed water in the form of tiny speckles on the surface of a specimen before he subjected it to different loading conditions. When the sample crumpled, cameras kept out to take images of the process kicked into action which were later fed to the computer to generate a computer image taking into considerations the points where stress is induced. According to the researchers, the method can exactly predict physical properties of any material with precision and high accuracy.

In creating a real life model, the researchers used a sample of TRIP 690 which a grade of steel much similar to the one actually used to make the oil rig riser in the Mexico's oil rig accident. They could have used X70 itself but had to settle with TRIP 690 due to unavailability of the specimen. However at the end of result, it is clearly evident that the

Scientists have reconstructed the incident accurately. Wierzbicki’s team made computer simulations of the Gulf oil accident by attaching a large diameter pipe to the rectangular platform representing the rig. Then the rectangular platform was made to sink by tilting it at an angle which there by generating a model of sinking rig. The bends in the pipes and the cracks induced by the action were studied with the help of color coded signals. In the color codes, the regions colored Green, Blue, Yellow and Red showed an increasing degree of cracks. Means the regions colored green were intact while the red ones symbolized the cracked regions.

Prof. Jorgen Amdahl, from Norwegian University of Science and Technology firmly believes that the proposed model and methods adopted by Mr. Wierzbicki will have a positive effect on the future oil exploration system.

Amdahl says-

The process takes into account all ranges of stress states. The approach will be very useful for the oil and gas industry with respect to assessment of pipe behavior under accidental stresses.

The research do not provide us with exact solutions as to what should be done in such a situation, it does however provide us with a prior signal of the strength of materials at which the material will be broken.

Speaking of his research Wierzbicki said,

The deeper you go in the ocean, two or three miles down, the stronger material you need to withstand the pressure. But stronger materials are more brittle and break more easily. So there’s a difficult problem for the offshore industry, and I think they can learn a lot from us.