Alibaba
In motor failure cases, more than hal♥"∏f of the failures are caused by the ↕•σ☆quality of the bearing sys÷•tem; the mildest ones are m₽∞™αanifested as bearing noise,>& and the most serious ones are the di≥↔sintegration of the bearin∏'•g, which may cause t£ ↔he motor to sweep th∏±✔e hole or burn the winding; in the↕× process of dissecting such faul∞∏ty motors, at least one of the f↑≠≈♠ollowing symptoms caα₽&Ωn be found: dry grinding s>tate of the bearing or lack o<βδ≤f oil; the grease turns black and ☆•clumps; the bearing has ob α☆×vious mechanical or electrical corr♣•≥≤osion damage; the motor with such prob•♥¥lems will show bearing noise in the ear∏≥₹ly stage of the fail♥φ ure; because the object of the failu®•≥∑re is clear, people are li€≈&kely to blame the problem on '±£the quality of the be♣Ω∏aring, and naturally ignore th•γ≥¥e influence of grease and relate↕∞β'd factors.
Bearing rotation an♦&♣←d movement cause grease to be thrown÷€≈< out:
The design of the bear☆§ing system is a key →>♠link in determining whether ↔↓↑the motor can drive the equipment to op₽$erate reliably. For cy≤®≈lindrical roller bearings with separablε↕e inner and outer rings, e ≈φ≥specially when the positioning end is n₽α'↑ot well controlled, a certain ra★∞nge of axial movemen☆• ≤t will occur. Sometimβ¥es the frequency and intensity of tσ↑<he motor shaft movement just reach ←γ® a level similar to that of a ™αΩvibrating screen, so that the €↔≈grease in the bearing cont∞÷inues to move in a certain÷πε direction, so under th≠ε÷♣e centrifugal action of the bearing€λ> during the rotation of the bearing≥£λ, the grease is constantly th♥≠γrown out of the bear±✔•ing cavity. The actual inspection p §♠rocess found that for the α✘case of a large inner cavit★εy of the bearing system, there is no ✘÷good constraint on t ♠★≤he grease being thrownσ out, which ultimately canno↑€←↕t play a lubricating effect and ✘≥✘¥will hinder the heat dissipatσ≠ion of the bearing system.
For this problem, the fo ←γllowing measures should₩>" be taken according to t★™>®he specific situation♥ <: appropriately change the inner¶♥ cavity size through t∑↕£he inner and outer covers of the bear±©ing, add an oil baffle or oil throwin→↕↕g device, and check the positio☆∞ning relationship of each bearin"♥₽g pivot.
Reasons for grease deteriφ ₩∏oration:
The main reason for ←σφgrease deterioration is that the b•©₽σearing heat is higher th≈₹♠an the working temperature o®©f the grease. If there is no pr★§☆βoblem with the processing an ↕d assembly accuracy of the∏"' bearing system, it may be related Ω÷to the selection of greas¶ ×e, especially for motors running iδ±n high temperature envir≈↑onments. There are many ÷✘®other reasons for bearing heating π §☆problems, which will not be repeated he$✔↓←re.
Bearing heating and grea≤se degradation failure are directly relα♣×ated to two factors. Bearing heating ₹πλ€to a certain extent will ca✔☆use grease degradation,÷±< and grease degradation wσα✘ill aggravate bearing heating.
The grease running in the bearin≠γg is damaged by mechanical f§Ω∏orce, which makes the fibers of the♣ δ thickener broken and ∏♣shortened, reducing the a$♦'↓bility to maintain t♥÷λ✔he grease structure, tha"£♦t is, the viscosity changes. If∏★ the viscosity changes±€₩♣ greatly, it will cause leakag¶e from the working surfaceδ→. At the same time, ₩•during operation, the grease will be→≤↔' affected by the temperature rise.♣✘✔ Due to the colloid destruction of ✔♦"the grease, the base o✔↓il will evaporate or part of the ≥↓αbase oil will be lost, which ≠♠"will reduce the oil £÷✘content of the grease and>£← may also cause oxidation and deterio→$≈←ration.
From the analysis of the actual op♣±δeration effect of motor produ¶♣cts, the matching relationship betwe∏©<en bearing grease anσ••₩d bearing system and e≥&≤"nvironmental conditions is very imp☆€ αortant. Moreover, foλשr any motor, the cost of grease ✔€γ€accounts for a very small proportioε≈✔♥n. The use of high-quality grease c€₽<an greatly reduce bear♣♣☆↕ing system failures.
