Heat insulation board used for heat exchanger

The utility model discloses a heat insulation board used for a heat exchanger. The heat insulation board used for the heat exchanger comprises a board body and is characterized in that the board body is provided with a plurality air inlet holes with flanges, air outlet holes are formed in positions corresponding to air outlet end cooling tubes of the heat exchanger and contained all the air outlet end cooling tubes, the number of the air inlet holes and the positions of the air inlet holes are corresponding to air inlet end cooling tubes of the heat exchanger in a one-to-one mode, and each flange is inserted into each corresponding cooling tube. The heat insulation board used for the heat exchanger is capable of enabling waste gas to directly flow into the cooling tubes and not to directly impact a main board, effectively reducing heat stress of a welding joint of the main board and the cooling tubes, improving reliability of the heat exchanger, enabling a heat exchanger flange matched with the heat insulatio