A bearing is an important structural member that provides rotational movement of parts during rolling or linear movement. It is an assembly consisting of two round plates: the outer and inner rings. A separator with several balls is inserted inside the structure, which ensures the torsion of the mechanism.
Later in the article, we will look at how bearings are assembled at home. But first, we will figure out what these details are and what types they are.
Types of bearings
Bearings vary in type of construction and material of manufacture:
- The most common in household appliances and ball bearings are familiar to consumers . They are placed on devices that do not experience heavy loads. For example, electric motors, woodworking machines, gearboxes. They are used in medical equipment.
- Spherical bearings have the highest strength and can withstand even extreme loads, so they are installed in mechanisms such as crushers or pumps.
- Needle bearings are often used in small parts of household appliances. Thin cylindrical sticks are inserted in the mechanism of such products, resembling a needle in shape.
- Cylindrical bearings are considered to be one of the most reliable bearings withstanding sufficient loads. They are used in mechanical engineering: in automobile, aviation and railway transport.
Ball bearing device
Consider the first version of the product. Such a device consists of two metal plates that have special grooves or the so-called raceways in the middle of the planes. On a large outer ring, such a groove is located inside, on a ring of a smaller diameter - on the outside.
A separator with inserted balls is inserted into the center of the structure. Thanks to this system, the rolling occurs smoothly. When mounted on a mechanism, bearings can also be wiped with lubricants for better rotational movement.
The separator consists of two parts - the so-called semi-separators. These two parts are then soldered using spot welding. Sometimes they are mounted on a mounting antennae or by riveting. Such devices may have one or two rows of balls.
Roller bearing device
Another embodiment of the device for rotating parts consists of rollers. These are metal cylinders or cones of the same size, which are inserted into the separator in the middle between two rings. Such products are much stronger and more reliable than ball bearings. They are used in mechanical engineering: automobile, aviation and railway transport.
There are roller inserts of a cylindrical or conical shape, which are placed in the inner part of the part in one or several rows. The cylindrical rollers, after the bearing is assembled, are installed in guillotines, powerful gearboxes and electric motors, machine tool spindles or pumps.
The conical shape is used in products for helical mechanical gears, in automobile transport, in the hubs of cars.
Bearing assembly
At enterprises, assembly processes are performed on special equipment, namely shafts. Before assembling the bearings, check the quality of the surfaces of both the shaft and the product rings. They should not be damaged in any way: scratches, burrs, nicks, painted pictures, metal corrosion spots, cracks.
All surfaces are thoroughly wiped, dried and lubricated with a thin layer of lubricant before assembling the bearings. Only then can assembly operations begin.
Mechanical way
This method is used for small sizes of parts, the inner diameter of which is up to 60 mm. When assembling, the main thing is to observe one important rule: the force during mechanical coupling of the outer and inner rings should not be transmitted to the separator. It appears only on the ends of the rings.
It is also strictly forbidden to knock on the ring. Light strokes can be applied only through additional material, for example, a sleeve made of soft metal. At enterprises, these tasks are performed by automated conveyor belt machines.
Step-by-step assembly sequence
Let's look at how to assemble a disassembled bearing:
- It is necessary to put the outer ring in a vertical position and lubricate its groove from the inside with a thick, almost solid lubricant, but not to the end of the circle, but about three quarters of its surface.
- After this, the balls must be inserted alternately with thin tweezers, recessing them into the lubricant.
- Before assembling the ball bearing, you need to attach the inner ring to the balls, squeezing it a little. Then we carefully start scrolling in a circle so that they are distributed at equal distances from one another.
- Then we insert the separator and rotate it so that the balls find their place in the recesses.
- When all the balls snap into the compartments, you can wipe the grease with a dry cloth. For complete washing, it is advisable to use kerosene.
Bearing repair
There are times when the bearing in the device began to turn poorly. There may be several reasons. For example, dirt has accumulated in the grease. In order to give the product a new life, it must be thoroughly cleaned and washed. You can use gasoline for these purposes.
Next, proceed as follows:
- First you need to remove the stuffing box cover, hold the bearing in a vice and carefully drill the rivets of the cage with a thin drill. This can only be done if there are several old bearings, and in the event of a breakdown of the cage or one of its halves, it will be possible to assemble a whole other product.
- All rivets on the separator must be carefully cut with a grinder so that the half is whole, not bent.
- The next step will be cleaning the rings and shaken balls of dirt, washing parts in gasoline. At the same time, it is necessary to check the condition and integrity of each bearing element.
- Then the most difficult stage of repair work is putting all the balls back into the structure.
- Before assembling the bearing, the rings must be sanded. First, the first half of the separator is inserted, then carefully, one at a time, in each groove you need to place the balls so that they fill all the holes.
- After that, rivets are made. You can use copper wire.
- Next, apply a layer of fresh grease and close the stuffing box cover.
Bearings so repaired in units, a motorcycle or a machine are not recommended. You can use them for household purposes in a summer cottage or for a child to repair a scooter.
How to assemble a small bearing?
Now a spinning toy called spinner is very popular among children. But what does it cost a child to drop such a spinning object on the floor? There were times when a baby ran to his parents in tears and wailed that the spinner had broken.
And most often the problem for parents is how to assemble a crumbling bearing. Small items are much more difficult to assemble, but quite possible. To do this, you will need to use thin tweezers.
Most often, such toys use simple ball bearings without cages, in which the balls rotate along the grooves of the rings. To assemble all the parts together, you need to use the mechanical assembly method described above. If you can’t succeed, then you need to use knowledge about the properties of metal.
One of the rings must be put in warm water, and the other in the refrigerator. From frost, the metal will become smaller, and will expand after heat treatment. Thus, putting them together will already be much easier. Good luck