Third, the improvement measures According to the sealing failure reasons, we targeted from the following aspects of the technical transformation: 1, change the sealing structure according to the specific conditions of the pump conditions, we use the Ai-318 type card End mechanical seal (cartridge), the main features are as follows: Precise centering by automatic locking ring. Adjustable gland can be used directly with the commonly used bolts, container-mounted structure easy to install. Spring is located outside the auxiliary seal, completely separated from the media to avoid the jamming of the spring. Ring is used in the overall floating non-mosaic, static ring is a computer analysis, the design of the Z-shaped, its advantages are good heat dissipation, heat should not accumulate. 2, the use of diesel components for flushing fluid Residual oil components due to overweight and contain more impurities and polymers, the flushing line blocked and cause mechanical seal damage, it must choose the right flushing fluid. In accordance with the ethylene process, the diesel component of the E-DA103 column will be mixed with the residual oil to produce the final product. We believe it to be more suitable to use mixed diesel as a rinse solution for the following reasons: 2.1 The blended diesel component is clean, Good compatibility. 2.2 mixed diesel components of the pressure and temperature are suitable for residue pump conditions. Mixing diesel oil fraction above 300 ℃, while the residue of the working temperature of 170 ℃, mixed with diesel fuel for flushing will not be vaporized, effectively avoiding the pump cavitation. E-DA103 bottom circulating pump E-GA105 pump outlet pressure of 0.54MPa, the outlet temperature of 80 ℃. The pressure in the sealed chamber of the E-GA103 pump can be estimated by the following formula: P = (inlet pressure + outlet pressure) /2=0.438MPa The rinse liquid pressure is about 0.1 MPa greater than the pressure in the sealed chamber and is well suited to direct E-GA105 pump outlet can be introduced into the sealed chamber. 2.3 Mixing diesel components as the rinse solution is the most economical, almost useless to increase any input, because this part of the diesel fuel components and ultimately to be mixed with the residue. E-GA103 two pumps from January 2001 began using the mechanical seal card, from the scene point of view the sealing effect is very good, there is still no signs of leakage until now, the service life of up to 2 years. The original 8B1-P machine seal each set price of 960 yuan, 2500 yuan each card-type mechanical seal, mechanical seal spare parts costs within two years alone save more than 1 million yuan, by removing the seal flushing to improve the effective pump flow and economic benefits It is obvious. Fourth, the conclusion Through the transformation of the mechanical seal of the residue pump, and the rational use of flushing fluid to improve the performance of the mechanical seal to solve the frequent leakage of mechanical seal problems and reduce equipment maintenance and repair costs to ensure the continuous and stable device produce.