Automatic drainage and pressure relief device for engine exhaust pipe

The utility model discloses an automatic drainage and pressure relief device for an engine smoke exhaust pipe. The utility model belongs to the field of waste heat power generation, generator set, a smoke main pipe is arranged on the generator set; the flue gas main pipe is connected with the plate heat exchanger I; the upper end of the flue gas main pipe is connected with a chimney; a flue gas bypass is arranged on one side of the flue gas main pipe; a valve II is arranged on the flue gas bypass; the smoke main pipe is provided with a water outlet, the water outlet is provided with an automatic pressure relief drainage device, one side of the generator set is provided with a cylinder sleeve water circulation system, the cylinder sleeve water circulation system is connected with a second plate heat exchanger, and a hot water circulation system is connected between the first plate heat exchanger and the second plate heat exchanger. According to the smoke heat recovery device, the pressure in the smoke exhaust