Downhole Conditions And Load Impact Study On The Cement Ring

In the process of building the hole and production, casing and cement mantle withstand the loadings together, any one is damaged, it would shorten the using time of the other one and the oil well, so we couldn't consider the integrity of one, and should do the reaserch of keeping the whole of casingcement mantle integrity. Faliure process of the casing_cement mantle is very complicate. Technique and practice used in drilling, producting and development programe all affect it. In recent years, many scholars have studied the causes and mechanism of the casing failure and many mechanisms of casing failure were recongnized, but when study how to design the parameters of the cement mantle, how to protect the casing is mostly considered and ignore the important function of keeping the cement mantle integrity. Hence, at the basis of doing reaserch of the stress and the working condition for the whole using process, we can keep hermetization by improving the technics and design the parameters in reason. The idiograhic contents as follow:(l)At the foundation of doing reaserch for the whole using process of the cement mantle and combine the designing methods, we can get the stress of the pressure test and the nonuniform formation loadings because of the water injection and the acid fracturing may lead the cement mantle to fail, but it haven't considered all of the conditions now.(2)Based and explained casing and cement bond elasticity coupling mechanical moldels by using the theory of the elasticity mechanics and combine the pressure test technics, and workout correlative programme.(3)Analyse the stress of the cement mantle when doing casing pressure test, and gotten out that it may lead the cement mantle to failure.(4)Because the methods of the casing pressure test may lead the cement mantle to fail, this artice haven gotten out new methods of the casing pressure test based on the anlysis of the present methods of casing pressure test to achieve the aim of protecting the cement mantle and test the leak tightness of the casing.(5)Based and explained formation, cement bond and casing elasticity coupling mechanical models under non-uniform formation stress by using the theory of the elasticity mechanics, and workout correlative programme.(6) Analysing the stress of the casing_cement mantle which were affected by the parameters of the cement.(7)Bring forward a new method of casing design which will consider the non_uniform loadings combine the present method of the casing design, and bring forward how to design the cement mantle perfectly based on the method of the casing design.(8)Design software of cement parameters is programmed, by it we can analyse the stress...