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1. Scratch (two-body abrasive wear) /*250*250 was created on 2017/12/25*/ var cpro_id = 'u3171089';
Hard particles moving along with the shaft diameter and conflicting external touch; this is the lower touch stress on the surface of the particles and the metal; they are lined with scratches on the outer surface of the bearing shell, and the hard particles embedded in the outer surface of the bearing shell are also on the outer diameter of the shaft diameter. Line-shaped scars are drawn; they are all called scratches. Scratches are two-body abrasive wear; the direction of linear flaws is common to the direction of shaft diameter movement.
Lubricating oil film breaks; the hub peak of the shaft diameter will also scratch the bearing; it has many linear scratches; it is also two-body abrasive wear.
The hard particles are embedded in the outer surface of the bearing shell and fall again; the scratches that make up the point-like scars.
Most of the above particles are iron and sand.
The scratching causes the conflict to be roughened; then the bearing capacity of the lubricant film is reduced; and it will form a new hard particle and hub peak that can scratch the conflict; it constitutes a vicious circle.
2. (three-body) abrasive particles wear smaller hard particles into the bearing gap; hesitant between the two conflicting appearances; extremely high touch stress on the conflicting appearance; constitute three-body abrasive wear; similar to the grinding effect; The outer diameter of the shaft diameter wears. The high contact stress between the hard particles and the conflicting appearance causes the conflicting appearance of the resistant metal to plastically deform or fatigue damage; the conflicting appearance of the brittle metal appears to be brittle or fall.
The scratches of abrasive wear are also linear; the direction is also common to the direction of the shaft diameter.
When the marginal touch, short oil or oil film breaks, the abrasive wear will be severe. The wear of the abrasive will incur a certain size and shape change of the shaft diameter and/or the bearing, the loss of precision, and the increase of bearing clearance; Bearing performance deteriorates sharply before the expected life.
3. Bite (gluing)
In the state where the lubricating oil film breaks or lacks oil; the large conflict factor causes a lot of conflict heat; the bearing temperature rises. At high temperature; the low-melting metal of a conflicting appearance adheres to another conflicting appearance due to softening; The shearing effect is caused by the rotation of the shaft diameter; the adhered metal is detached from the original appearance; it is transferred to another conflicting appearance; the concave and convex flaws which constitute the conflicting appearance are obvious. The damage is adhesive wear.
When the bite is present; the conflict increases sharply; the bearing temperature rises further; it constitutes a vicious circle. When the adhesion is severe; the power of the shaft diameter transformation can no longer cut the bonding point; the shaft diameter movement will be stopped; Hold the axle"; the bearing is completely damaged.
4. Weak wear and fatigue wear is also called fatigue damage. Under the repeated effect of cyclic load; in the straight direction with the sliding direction; the conflicting appearance shows fatigue crack; the crack is straight to the outer surface of the bearing bush; the lining and the backing are connected Go to parallel with the appearance of the conflict; the final data is dropped from the appearance of the conflict; constitutes a pit-like damage.
5. When peeling the bearing bush; if the lining and the backing are lacking or poorly connected; during the working process of the bearing; under the effect of the load; the information of the partial lining will be peeled off from the bearing. The peeling is similar to the fatigue falling. However, the fatigue around the pit is irregular; the poorly formed peeling pit is similar to the lubrication. Corrosive lubricating oil is continuously oxidized during use; oxidation often attacks weak organic acids; it is corrosive to bearing materials, especially lead in cast copper-lead alloy; it is characterized by lead falling in dots; roughening the appearance.
Strong inorganic acids are more likely to corrode steel shafts.
The tin in the tin-based bearing alloy is oxidized; a black hard coating layer composed of SnO2 and SnO is formed on the outer surface of the bearing shell; the hardness is in the range of 200-600HS. This covering layer is extremely harmful to the bearing; it is very hard; Scratches the outer surface of the journal; and makes the bearing clearance smaller.
7. Corrosion (1) Cavitation cavitation is the appearance of external damage when the solid surface and the liquid touch and move relative to each other.
When the lubricating oil is in the low pressure zone of the oil film; the oil will form bubbles; after the bubble moves to the high pressure zone; the bubble collapses under the pressure effect; the impact force and the high temperature occur in the collapsed sputum; the solid appearance is here Under the repeated effect of impact; the data is exhausted and dropped; the appearance of the conflict is small pits; and then a spongy wound is developed.
Heavy-duty, high-speed; and the sliding bearing with large changes in load and speed; often cavitation.
(2) The fluid corrosive fluid violently impacts the solid appearance to form a fluid corrosion; the solid appearance presents a point-like flaw; the appearance of such damage is more lubricated.
(3) Electro-corrosion due to electrical leakage of motor or electrical equipment; sparks appearing between conflicting appearances; forming point-like scars on the appearance of conflicts; characterized by the fact that the damage reciprocates on the outer surface of the harder journal.
8. Fretting wear on the lining and backing; the interface between the bearing bush and the bearing housing; due to the combined effect of micro-oscillation (slip) and oxidation between the metal surfaces; constitutes adhesive wear, oxidation (corrosion) wear and abrasive wear 3 Compound wear in a variety of ways; called fretting wear; it will form a point-like scar on the interface.
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Type of damage in plain bearings
Source: Bearing network time: 2013-07-19