| Oil-well tube is the important equipment during the oil-field reservoir reconstruction andproduction. It works in severe environment during the process of acid fracturing andproduction. It withstands the interaction of mechanical force and chemical coupling effect. Asa result, it is often destroyed by the severe deformation, fracture and partial corrosion. andcauses the down-hole accidents. Using the theory of Fluid Mechanics and ElectrochemicalCorrosion, taking material of P110and super13Cr as the research object, This paper carriedout the induced corrosion research of tube in the action of fluid under high velocity (themaximum velocity of up to40m/s) in the designed impingement jet experiment device. Mainresearches are as follows:Firstly, When the flow velocity is10.0m/s, the corrosion rate of the two materials reachto the maximum, at this time, the corrosion potential close to the anodic dissolution reaction,polarization curve results show that the corrosion process was controlled by both the cathodeoxygen diffusion and the anodic dissolution reaction, so the corrosion rate is the largest, thecorrosion product film thickness is thinnest and most loose.Secondly, When the flow velocity is below10.0m/s, with the increase of flow velocity,the two materials of corrosion rate increased gradually, the corrosion potential is graduallyreduced, the cathodic polarization curve is mainly controlled by oxygen diffusion. With theincrease of flow velocity, the thickness of the corrosion product film gradually thinning, theproduct film also by compact becomes loose.Finally, When the flow velocity is over10.0m/s, with the increase of flow velocity, thetwo materials corrosion rate decreased gradually, the corrosion potential is gradually increase.The anodic polarization curve appeared obviously passivation tendency. With the increase offlow velocity, the thickness of the corrosion product film gradually thinkening, the productfilm also by loose becomes compact. |
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