Russian researchers develop a new method of oil well equipment testing
Russian scientists have developed a special method of nondestructive testing of drilling rig elements in oil wells, which will ensure the efficient oil production and reduce the time and cost of equipment repair, reports Chemical Industry. The prospective research funded by the Russian Science Foundation was conducted in Peter the Great St Petersburg Polytechnic University (SPbPU).
Scientists say that the use of traditional nondestructive testing technologies is nowadays ineffective for the diagnosis of modern structures made of corrosion-resistant and high-strength structural materials. For example, microcracks caused by metal fatigue, which occurs during repeated loading and unloading of the structure, cannot be detected by conventional methods like ultrasonic diagnostics. Thus, there is no effective method of nondestructive testing that allows calculating the remaining tool life. Moreover, the last major results in the field of nondestructive acoustic testing were obtained more than thirty years ago and didn't cover the cases of inelastic, irreversible structural deformations, which are more significant for technical diagnostics.
The new method based on the study of mechanical stresses, plastic deformations and microcracks in industrial structures allows experts to give numerical estimates of damage throughout the structure. The research results obtained for the cases of plastic deformation of samples made of the high-strength steels have confirmed the effectiveness of the new technology. It can be extended to a wide class of deformation and lead to direct practical application in industry. Europe's largest industrial manufacturing company, Siemens, has already expressed its interest in the application of the method of nondestructive testing to gas turbine engine blades.
The researchers are now going to work on a technology to determine the internal structure of oil layers and the nature of its damage. It can help predict the consequences of drilling and hydraulic fracturing and provide an opportunity to diagnose working wells. If the scientists find the solution, it will ensure efficient and safe operation of Russia's energy complex.