Metal heat treatment heating furnace

The utility model discloses a metal heat treatment heating furnace and relates to the field of metal treatment furnaces. The metal heat treatment heating furnace comprises a heating furnace body, a pressure relief pipe is arranged on the heating furnace body, an exhaust pipe is fixedly connected to the pressure relief pipe, the exhaust pipe communicates with the pressure relief pipe, a filter box is fixedly connected to the exhaust pipe, an activated carbon filter screen is movably clamped in the filter box, and the activated carbon filter screen communicates with the pressure relief pipe. A pressure relief piston is slidably connected into the pressure relief pipe, and an adjustable pressure spring is arranged at the top of the pressure relief piston. The metal heat treatment heating furnace is simple in overall structure and convenient to use, the pressure relief pipe is additionally arranged on the heating furnace body, so that it is guaranteed that the internal pressure of the heating furnace body is with