The Study On Rational Flooding Pressure In Casing Damage Area Of No.2 Block Of Pubei

As for great majority routine oil fields, water injection is to keep the reservoir energy , makes an oil field get rational high-effect development guarantee. Flooding pressure decides the quantity of injected water and the effect of water injection. Too high flooding pressure is easy to damage the casing pipe; too low flooding pressure can not make the reservoir energy get effective complement. Therefore rational flooding pressure opens up oilfields in water drive be a key. The casing damage is seriously in casing damage area of No.2 Block of Pubei, and formation pressure is extremely unbalanced . The oil well is not able to work regularly, and water injection is unable to restore formation pressure very well, which has produced disadvantageous effect to oil field development. By studying maximum allowable flooding pressure and the balance formation pressure,this study ascertain a synthesis adjusting scheme to reach control or slow down casing damage , to balance south and north pressure , to improve oil field development ultimately. The mechanism of casing damage and the relation of water injection and casing damage is be studied. Extra-high flooding pressure leads to casing damage. So, water injection is unable to work well and formation pressure is difficult to restore, and this brought about the area formation pressure imbalance. Therefore it is useful to know that again producer-inject ability and maximum allowable flooding pressure, ensure that rational water injection can control of the casing damage and slow down formation pressure unbalance and reach rational high-effect exploitation ultimately. Firstly,the study have built calculation model of maximum allowable flooding pressure. According to reality set of casing damage area of No.2 Block of Pubei, obtain various method to calculate the parameter, and carry out verification on various methods. The accurate rate satisfies project need. Then,analyses producer-inject ability,combining balance of injection to production ratio, and builds balance picture in that area. Finally, according to system balances analysis result and the calculation result of maximum allowable flooding pressure, uniting reservoir body distribution situation studies, give a system of synthesis adjusting schemes which contain rejuvenation of casing damage, fracturing, and other adjusting measures. Through Numerical modeling, one year after the formation pressure unbalance improve obviously. For portrait direction pressure distribution, the large difference pressure between layers improves noticeably.