Mechanical seal device and application requirements Mechanical seal is a high-precision mechanical equipment component. Its performance and service life are greatly related to the operating conditions, accuracy and sealing device of the host. Therefore, it is necessary to follow The following requirements should be carried out: 1. Precautions before installation 1. Correctly select the appropriate type of mechanical seal and data combination according to the working conditions and host conditions; 2. When the pump or other similar rotating machinery equipped with mechanical seal is in operation, the rotor is axially String momentum≤0.3mm 3. The step of the shaft (or sleeve) of the mechanical seal of the device must have a chamfer of 3×10°, and smooth transition, and its roughness Ra≤1.6. 4. The surface roughness of the shaft (or sleeve) of the mechanical seal part of the device is Ra≤1.6, the runout service is ≤0.04mm, and the standard service is h6. 5. The surface roughness Ra ≤ 1.6 of the sealing end cover and the auxiliary sealing ring of the mechanical seal static ring of the device, the standard service is H8, and the straightness of the positioning end facing the shaft ≤ 0.04mm. 6. For mechanical seals, it is necessary to clean the shaft (or shaft sleeve) seal cavity, seal end cover and mechanical seal itself to prevent any impurities from entering the seal part. 7. When the device stops the ring, especially the carbon graphite ring, it is necessary to be extra careful to press in. 8. When the temperature of the conveying medium is too high, too low, or contains impurity particles, flammable, explosive, toxic, etc., adopt corresponding blocking, flushing, cooling, and filtering methods according to API682 specifications. 9. According to the device operation manual or sample, ensure the device size of the mechanical seal. 10. For mechanical seals driven by tension springs, the rotation direction of the tension spring should be selected reasonably. Generally, from the motor end to the impeller end, when the shaft is clockwise, the right-handed tension spring should be selected, otherwise, the left-handed tension spring should be selected. 11. When the double-end mechanical seal is in operation, the pressure of the barrier fluid is 0.05-0.2MPa higher than the pressure of the medium in the sealed cavity. 2. Installation notes 1. The installation process should be carried out in a boring, dust-free and clean working environment, and the parts of the sealed cavity and seals should be clean and clean. 2. In order to reduce the conflict resistance, when installing, apply a layer of clean smooth oil or grease to the surface of the auxiliary seal. However, it is necessary to pay attention to when using ethylene-propylene rubber as auxiliary seals, do not touch with mineral oil or grease, and can be cleaned and smoothed with water or soapy water; 4. The operating height of the spring must reach the product sample or device drawing. Indicates the height of the device. 5. It is forbidden to knock or hit the seal during the installation process; when the sealing device is over, it is not allowed to hit or hit the shaft, shaft sleeve, sealing end cover, etc., so as to avoid damage to the mechanical seal and cause the seal to fail. 3. Matters needing attention when the sealing device is over and the equipment is turned on 1. It is necessary to exhaust the air in the sealed chamber, especially the double end seal with sealing liquid, and pay attention to exhaust air. When driving from the beginning, the suction valve should be opened first, and the motor should be turned on after the liquid (medium) enters the sealed cavity. For those media with crystallization, when starting from the beginning, the crystals on the sealing surface, tension spring and other related structural parts should be washed clean with lotion before driving. 2. Before starting the equipment, check that the resistance of the shaft is normal and even, and no jamming is allowed. 3. Before the equipment works, the sealed cavity must be filled with medium, adhere to excellent smoothness, and prohibit dry conflicts, which will cause the seal to fail. Keywords: mechanical seal