Study on the Measure of Precaution against Casing Deformation Well in Shengli Oil Field

The total number of casing deformation wells in Shengli oil field has reached 2539 at the end of 2002 since Shengli oil field entered into comprehensive production in 1970, which greatly restricted its development. The casing deformation types mainly include casing deformation and casing breakage. The casing deformation mechanism includes bed glide and mudstone creepage which cause casing deformation or breakage under uneven ground stress. Aiming at the cause of casing deformation and breakage, the correspondingly preventive action was made.One is to prevent extraneous force from exceeding casing yield strength, the other is to augment casing strength. Obvious anti-deformation effect is obtained with the application of actions.