Formwork support for tunnel portal ring beam construction

The utility model relates to the technical field of tunnel lining, and discloses a formwork support for tunnel portal ring beam construction, which comprises a connecting frame, a second connecting block is fixedly connected to the right side of the connecting frame, a limiting sleeve is fixedly connected to the right side of the second connecting block, and a second limiting ring is fixedly connected to the right side of the limiting sleeve. The outer side of the second limiting ring is slidably connected with a sliding sleeve, and the right end of the inner side of the sliding sleeve is fixedly connected with a first limiting ring. According to mutual cooperation of the connecting frame, the first connecting block, the limiting column, the second connecting block, a limiting sleeve, a sliding sleeve, a first limiting ring, a second limiting ring, a limiting ball, a spring and a clamping groove, rapid detachment between devices is achieved, and the limiting column can rotate in the limiting sleeve so as to d