Mechanical sealing device of desulfurization circulating pump

The utility model discloses a desulfurization circulating pump mechanical sealing device which comprises a fixed ring, a positioning ring, a spring seat, a reset spring, a movable ring, an extrusion pad and a sealing pad, pressure balance assemblies are installed in the spring seat at equal intervals, and each pressure balance assembly comprises a piston sleeve, a positioning sleeve, a piston plate and a floating ring. The piston sleeves are fixedly installed in the spring seat and form a circumferential array with the center point of the spring seat as the center point, the positioning sleeves are fixedly installed in the piston sleeves, and the piston plates are connected in the positioning sleeves in an up-down sliding mode. According to the mechanical sealing device, the sealing performance of the connecting position of an external object and the mechanical sealing device can be achieved, pressure is balanced by changing the sealing face structure of an existing mechanical sealing device and adopting the