Abstract: The displacement pointer of the constant force hanger of a high-pressure main steam pipeline was stuck with locking device which resulted in the thermal displacement blocking of the pipeline. Regarding such situation, the influence of the thermal displacement blocking on pipeline force, high-pressure cylinder force and torque was quantitatively analyzed by static calculation. The results show that when the displacement of constant force hanger was blocked, high-pressure cylinder’s force and torque coming from the pipeline changed greatly, and the maximum secondary stress of the pipeline increased accordingly.