The Luliang Production System N80 Steel Corrosion Rate Prediction Techniques

As long as Luliang oil field is developed continuously and it's comprehensive water content ratio raises year by year, there are comparatively more serious corrosion appearance in tubes , casings pipelines of Luliang oil field, corrosion becomes the significant hidden danger that effects safe production and economy of Luliang oil field, so we should analyze carefully the corrosion mechanisms, corrosion actions and effect elements of tubes,casings in Luliang oil field product system, in the mean time we should take some anticorrosion measures and some corrosion prediction scheme, these works not only have the profound theory sense but also have wide-ranging pragmatic value.First of all , in the paper the author analyzed carefully the corrosions and corrosive environment in the oil field product system, connected abundance of data form lab and spot, consulted information refer to the corrosion of domestic and aboard. Make a deep research about mechanism and applicability of forecast modal, mastered roundly it's ion composition of output water, the content of corrosive gas in output gas, the temperature and pressure of oil well in the bottom , corrosive types and corrosive mechanisms , these supply the powerful base support for the follow-up work.Secondly, by analyzing weight-loss method of steel slice experiment, the author study some factors that effect corrosion rate of N80 , and then put forward some laws of the corrosion rate that is relate to temperature, the partial of CO₂, pH, the ion-chroma of Cl^-,SO₄^2-,Ca²⁺,Mg²⁺ and HCO₃^- , subsequently by using dynamic corrosive experimental data, some corrosive factors are sorted and the main factors are founded.Applying grey system and mathematical statistics theory to the dynamic corrosive experimental data, get focus on the mostly important factor to tubes , casings pipelines of Luliang oil field. The action put into effect to the antisepsis measure of Luliang field.The prediction of corrosion rate in oil field product system is always a hot problem which oil scientific and technical personnel comparatively concerned, by synthetically comparing some kinds of prediction method ,finally neural network , grey model and grey neural network model is adopted to predict the corrosion rate of N80 steel, the application result of BP neural network shows that the prediction with this method can achieve better utility. By using grey neural network model, the fluctuation of data sequence is weakened by the grey theory and the neural network is capable of processing non-linear adaptable information, and the GNNM is a combination of those advantages.The last, the corrosion prediction system is developed, which the method programming with VB, examined after some example, the process of realization and a sample program both indicate that method is sample and convenient, so it may be used widely in Luliang oilfield product system.