Auto water pump bearing up. the dynamic causes and solving measures

Auto water pump bearing in operation will appear in the process of dynamic fault phenomenon, the author is to analyze the reasons for this problem and the solving measures. Motor pump is the key components of the engine cooling system, water pump bearings under the action of axial load, channeling move that occurred during the bearing hole out failure condition easy to cause serious security hidden danger. So to analyze the invalidation cause of bearing channeling move and it is necessary to formulate the corresponding countermeasures. Shown in figure 1 is a typical auto water pump structure, the water pump bearing by pulleys at the end of the input torque, at the other end of the impeller rotates, centrifugal force is used to transport coolant, pulley front fan with the pump running, to cool the water tank of the vehicle to cool. Here are the influence factors of the auto water pump bearing channeling dynamic failure analysis. The influence of temperature change pump usually USES the interference fit between bearing and housing, the bearing can withstand the axial load. When the vehicle running on the pump temperature from room temperature gradually rises to a higher working temperature, the parts will be linear expansion along with the rise of temperature. When has the cooperate relationship between bearing and housing linear expansion coefficient difference is bigger, the change of temperature will lead to the change of the over surplus quantity of the, and transform the emergence of the bearing load. In the case of a certain type auto water pump, ZAlSi9Mg shell material for aluminum alloy, bearing materials for GCr15, design with size of phi 30 x7 / h6, when its temperature from room temperature 20 ℃ to 90 ℃ temperature, the changes of the over surplus quantity of the theoretical calculation is as follows. First of all, according to the phi 30 x7 / h6, tolerance and cooperation manual interference quantity to zero. 043-0. 077 mm, check material manual material linear expansion coefficient are shown in table 1. Table 1 material linear expansion coefficient is, the expansion of the hole and shaft amount for the Δ hole = * 23 * 10 to 30 6×（ The 90-20) = 0. 048, 3 ( mm） Δ shaft = 30 x 11 x 10 - 6×（ The 90-20) = 0. 023 1 ( mm） Reduce the amount of interference Δ L = 0. 048 3-0. 023 1 = 0. 2 (025 mm） Ratio of the over surplus quantity of the calculation is as follows: take two sets of pump at 20 ℃ and 90 ℃ respectively test of its emergence load bearing, contrast curve ( See figure 2) 。 Experiment data analysis shows that temperature bearing load out to an average of 10. 7 kn, bearing hernia of the average load at 90 ℃ temperatures is only five. 9 kn, the temperature after the water pump axial bearing capacity decreased by 45%. Through theoretical analysis and experimental test shows that the change in temperature has great influence on the axial bearing capacity of bearing. So auto water pump design should fully consider the linear expansion coefficient of material and product factors such as temperature, when necessary, can use small linear expansion coefficient difference of materials, or use the auxiliary process such as elastic ring means to prevent the bearing to move out. A: what is the method of the pump shaft bearing damage repair next article: shaft even bearing manufacturer to introduce cylindrical hole bearing installation method related tags: auto water pump bearing, water pump bearings, automotive water pump bearings, auto water pump bearing related news which cases will fever auto water pump bearing thermal and bearing performance of engine cooling system of key parts of automotive water pump bearing water pump bearing why use general auto water pump bearing grease appears channeling dynamic circumstance how to deal with related products