In fact, oil casing collapse is a common damage form of oil casing. However, although it is relatively common, how can we prevent oil casing damage? The anti-collapse properties of petroleum casing have always been the key to our concern, and the prediction and application of the anti-collapse strength of petroleum-specific pipelines has always been the focus of scientific research.

It can be seen from the model that when D/S is in the plastic collapse and transitional collapse zone, the ellipticity is very obvious, and the ellipticity has become the process control factor that interferes with the primary specification quality of the compressive strength value; when D/S is in the When the residual stress is not significant in the elastic collapse zone or yield collapse zone, the nominal yield strength should be adjusted as much as possible. The K-T model better predicts the anti-fragmentation characteristics of oil casing at this stage, but its formula calculation coefficient depends on the level of each company. In fact, deep wells must not only consider the interference of high temperature on the strength of oil casing, but also the interference of high temperature on the elastic mold and Poisson's ratio of the pipe material. Such factors will eventually interfere with the pipeline's ability to resist collapse under service conditions. Ultra-thick wall casing is an effective way to resolve the problem of abnormally high-pressure formation collapse in deep wells.