The invention provides an
overpressure preventing device for a pump box of an
air separation plant. The
overpressure preventing device for the pump box of the
air separation plant mainly comprises a cylinder, a
flange, a blank
flange, a seal ring, bolts, a connection piece, a waterproof cylinder and a waterproof cover plate. One end of the cylinder is connected with the
flange in a welded manner.The flange is connected with the blank flange through the bolts. The large end of the bolt is in
spot welding with the flange. The blank flange can move in the vertical direction along the bolt. The
nitrile butadiene rubber seal ring is arranged between the flange and the blank flange in a padding manner and guarantees that the pump box is sealed in the
normal state. The waterproof cover plate isadditionally arranged outside the blank flange. The waterproof cover plate is welded to the waterproof cylinder. The waterproof cover plate, the waterproof cylinder and the connection piece constitutea waterproof
assembly. The waterproof
assembly is connected with the flange in a welded manner through the connection piece, and therefore it can be guaranteed that rainwater cannot enter the pump box. The
overpressure preventing device for the pump box of the
air separation plant has the advantages of being simple in structure, safe, reliable, reasonable, efficient, high in practicability and the like, the overpressure preventing device is suitable for small-sized isolating boxes achieving heat preservation with
pearlite, such as the pump box, a valve box and a collection box, and the situation that seal gas in the isolating boxes is at overpressure, so that safety accidents are caused can be effectively prevented.