Analysis of the reliability and safety of automobile pumps
CS20A Household Electric Screwdriver Set SUZHOU CREATION SPACE INTELLIGENT TECHNOLOGY CO.,LTD , https://www.mypkey.com
Automotive water pump is a motor that circulates the coolant from the engine to the water tank. The reliability and life of the automotive water pump is the number one priority. 1, due to high engine speed, and changes in operating conditions, the coolant temperature is high (about 90 degrees, the limit of 110 degrees), increasing the design of automotive cooling pump more difficult. Automotive cooling pump, the current domestic manufacturers do not pay much attention to the efficiency of the pump, in order to reduce costs, the general pump efficiency is about 30%. I know Japan's Honda, Mazda's automotive cooling pumps are 42-46% efficiency. Open impeller efficiency is very high, the manufacturing process is also very good. 3, car cooling pump should be said that one of the special applications of centrifugal pumps. Its design concept and principle are the same as those of centrifugal pump, but considering the special requirements of cylinder structure, technology and automobile engine, we can find that the design method of automobile pump is different from that of common centrifugal pump, and the width of impeller is wide The design of the volute shell is not completely in accordance with the design of the volute of the ordinary centrifugal pump. The current structure of the impeller used by foreign enterprises are more stamping impeller, low cost, high efficiency; leaf structure varied, with circular blades, straight blades, but also after bending blades and so on. 4, the reliability of the automotive pump first thing to consider is the axial force balance and cavitation performance. These two points in the design must be rigorous calculations, we usually use CFD calculations and forecasts. 5, because imports generally have a system pressure of 0.98MP, cavitation performance improvement, the easiest way is to increase the import of impeller, of course, the placement of the blade and the inlet angle of the impact of cavitation performance is also greater. 6, shaft seals, bearings for better reliability, are generally imported. The reliability of these delicate parts is even more important. 7, the pressure difference for the car pump generally require 140kp, according to our experience, manufacturers are designed at 200kp above, this is not taking into account the requirements of the system piping characteristic curve? Or design conservative? If you can drop to 14KPa, this can reduce the shaft power, improve engine efficiency. 8, to study and design of automotive pumps, you must test the characteristics of the vehicle cooling system curve, so as to be reasonable and scientific design. Car pump is broken, coolant is not circulating, then the engine if it is still running, the water temperature is too high, may lead to engine cylinder, this is in trouble. Therefore, driving the best people in the car to observe the habit of observing the car, like how much gasoline left as carefully.