Inhalation of air is a common high-temperature gear pump failure, the following to exclude the inhalation of air failure of this method: 1.CB-B type high temperature gear pump body and both sides of the cover for direct contact with the hard seal, if the contact surface flatness The pump can not breathe air easily when it is working. Likewise, the pump is also in direct contact with the gland and the air is easy to invade. If the gland is made of plastic, the gland is damaged due to temperature change The deformation, will make the seal lax and into the air. The way to get rid of this kind of trouble is: when the flatness of the pump body or pump cover can not meet the stipulated requirements, it can be grinded back and forth on the flat plate with the gravure sand in the form of a glyph, or grinded on a surface grinding machine Flatness does not exceed 5μm, and the need to ensure the verticality of the plane and the hole requirements; for the pump cover and gland at the leak, can be coated with epoxy adhesive sealing. 2. High-temperature gear pump on the shaft generally used to seal the oil seal. If the locking lip spring off, or the oil seal installed, or its lips were injured, aging, will make the back end of the seal often in negative pressure and inhale the air, the general can replace the new seal to be resolved.