To solve the problem of the maximum running depth of coiled tubing, the maximum tensile condition, frictional condition and buckling condition should be satisfied.

• 在油田使用连续油管柱作业中，求解连续油管的最大下入深度问题时，必须满足最大抗拉强度条件、摩擦阻力条件和屈曲变形条件及其确定的方法和原则。