Aircraft engine spindle bearing slide typical parts and factors

Main shaft bearing of aviation engine is important parts, if the aircraft engine spindle bearing failure, will directly affect the normal use of the engine, visible, such as defective spindle bearing, consequence is unimaginable. Here the bearing network (for short ） Aeroengine is mainly to interpretation of the main shaft bearing sliding failure. 1, aviation engine main bearing bearing slide rub fault mainly parts ( Typical parts) Example: two and a half inner ring angular contact ball bearing working surface smooth rub fault, as shown in figure 1 angular contact ball bearing structure 1 angular contact ball bearing structure and smooth ceng generally occur in double half ring roll ring road and a half, the delay phenomenon which have obvious, fault of spherical roller bearing a third color. Of course, there are wide and narrow slip ceng half ring, there is also a steel ball color and not slip of inner ring. Typical failure morphology as shown in figure 2 ~ 5: narrow figure 2 and a half ring sliding ceng appearance figure 3 and a half wide ring morphology figure 4 ball rub surface and sliding ceng trace figure 5 large narrow band steel ball surface discoloration roller bearing slip ceng injury is the main reason of the rotor weight is lighter, the bearing not form enough radial load; Is the main reason of the ball bearing slide ceng injury suffered by the axial load. In addition, the rolling element and cage when the excessive motion resistance of sliding rub fault. 2, main shaft bearing slide rub fault factors, 1) Rub caused by a lack of axial load sliding bearing in the case of lack of axial load, radial force on the bearing, and passed on to the steel ball could not form effective contact Angle, steel ball and two and a half circle of contact at the same time, forming a multipoint contact. Which sliding failure. ( 2) Inadequate radial clearance of the bearing inner ring for peach shape multipoint contact channel structure, under the condition of the radial clearance is insufficient, will cause the steel ball surface and the channel surface skid injury. ( 3) Caused by the steel ball spin slide ceng rotating at high speed and withstand the axial load of ball bearing, can produce a kind of deviating from the ring center and the centrifugal force along the radial distribution, make the change force of the bearing. Under the effect of centrifugal force, the steel ball with greatly increased the force acting on the outer channel, while reducing the force between the steel ball and the inner ring channel. Force on the inner and outer channel change, will affect the ball with the change of inner and outer contact Angle, the outer ring smaller contact Angle, contact Angle and inner circle. In axial load under certain conditions, the higher the speed of the bearing, the difference of the inner and outer contact Angle. If the inner and outer contact Angle difference is very big, can affect the friction state of bearing. The contact Angle is smaller, as the ball with the outer channel movement way is almost pure rolling state; Inside is the contact Angle on the channel change, make steel ball except under rolling moment also bear an additional moment, gyroscopic moment, the moment will make the steel ball inside is the spin sports channel, the direction of rotation is around the center of steel ball and the inner ring and ball contact point of the axis rotation, the direction of rotation to make contact with vice of sliding friction, the result will cause the contact with the inner ring channel of the surface of the steel ball slide rub wear, smooth ceng area with the size of the size of the contact Angle. ( 4) Caused by excessive axial load contact ball bearing slide ceng three at work, steel ball in contact with the bearing inner ring, and the bearing inner ring has a residual gap. When the residual clearance is zero or negative, will have more contact, resulting in sliding failure.