What is a deep groove ball bearing
Deep groove ball bearings are the most common type of rolling bearing.
The basic deep groove ball bearing consists of an outer ring, an inner ring, a set of steel balls and a set of cages. There are two types of deep groove ball bearings: single row and double row. The deep groove ball structure is also divided into two types: sealed and open.
The open type means that the bearing does not have a sealed structure. The sealed deep groove ball is divided into dust-proof seal and oil-proof. seal. The material of the dust-proof sealing cover is stamped steel plate, which only serves to prevent dust from entering the bearing raceway. The oil-proof type is a contact oil seal, which can effectively prevent the grease in the bearing from overflowing.
Single row deep groove ball bearing type code is 6, double row deep groove ball bearing code is 4. It has a simple structure and is easy to use, and is the most commonly produced and widely used type of bearing.
How deep groove ball bearings work
Deep groove ball bearings mainly bear radial load, and can also bear radial load and axial load at the same time. When it is only subjected to radial load, the contact angle is zero. When the deep groove ball bearing has a large radial clearance, it has the performance of an angular contact bearing and can bear a large axial load. The friction coefficient of the deep groove ball bearing is very small, and the limit speed is also high.
Deep groove ball bearing characteristics
Deep groove ball bearings are the most commonly used rolling bearings. It has a simple structure and is easy to use. It is mainly used to bear radial load, but when the radial clearance of the bearing is increased, it has a certain performance of angular contact ball bearing and can bear combined radial and axial loads. It can also be used to bear pure axial load when the rotational speed is high and the thrust ball bearing is not suitable.
Compared with other types of bearings with the same size and size as deep groove ball bearings, this type of bearing has a small friction coefficient and a high limit speed. However, it is not resistant to impact and is not suitable for bearing heavy loads.
After the deep groove ball bearing is mounted on the shaft, within the axial clearance range of the bearing, the axial displacement of the shaft or the housing can be limited in two directions, so it can be axially positioned in both directions. In addition, this type of bearing also has a certain self-aligning ability. When it is inclined 2′ to 10′ relative to the housing hole, it can still work normally, but it has a certain impact on the bearing life.
Deep groove ball bearing structure
Compared with other types, the deep groove ball bearing has a simple structure and is easy to achieve higher manufacturing accuracy, so it is convenient for mass production in series, and the manufacturing cost is also low, and it is extremely common. In addition to the basic type, deep groove ball bearings also have various modified structures, such as: deep groove ball bearings with dust cover, deep groove ball bearings with rubber seals, deep groove ball bearings with retaining grooves, and Deep groove ball bearings with large load capacity of ball notches, double row deep groove ball bearings.
Deep groove ball bearing types
Deep groove ball bearings are mainly used to bear radial loads, but are also commonly used to bear combined radial and axial loads. Especially when the rotating speed of mechanical equipment is very high, and it is not suitable to use thrust bearing, this bearing can be used to bear two-way pure axial load, and no maintenance is required during operation.
It is a kind of bearing with low price and wide application. Deep groove ball bearing models are: deep groove ball bearing (type 60000); deep groove ball bearing with retaining groove in the outer ring (type 60000N); deep groove ball with a dust cover on one side and a retaining groove in the outer ring on the other side Bearing (type 60000-ZN); deep groove ball bearing with dust cover on both sides and retaining groove in outer ring (type 60000-2ZN); deep groove ball bearing with dust cover on one side (type 60000Z); two sides Deep groove ball bearing with dust cover (type 60000-2Z); deep groove ball bearing with sealing ring on one side (type 60000-LS, 60000-RZ); deep groove ball bearing with sealing ring on both sides (60000- 2LS type, 60000-2RZ type); flanged outer ring deep groove ball bearing (F60000 type); flanged outer ring deep groove ball bearing with dust cover on one side (F60000-Z type); There are 11 types of flanged outer ring deep groove ball bearings (F60000-2Z type). [2]
According to the size of deep groove ball bearings, they can be divided into:
(1) Miniature bearings – bearings with a nominal outer diameter range of less than 26mm;
(2) Small bearings – bearings with a nominal outer diameter range of 28-55mm;
(3) Small and medium-sized bearings—bearings with a nominal outer diameter range of 60-115mm;
(4) Medium and large bearings – bearings with a nominal outer diameter range of 120-190mm
(5) Large bearings – bearings with a nominal outer diameter range of 200-430mm;
(6) Extra-large bearing—bearings with a nominal outer diameter range of 440mm or more.
Application of deep groove ball bearing
Deep groove ball bearings can be used in gearboxes, instruments, motors, household appliances, internal combustion engines, transportation vehicles, agricultural machinery, construction machinery, construction machinery, roller skates, yo-yo, etc.
Deep groove ball bearing installation method
Deep groove ball bearing installation method 1: Press fit: When the inner ring of the bearing and the shaft are tightly fitted, and the outer ring and the bearing seat hole are loosely fitted, the bearing can be press-fitted on the shaft first, and then the shaft together with the bearing.
Put them into the hole of the bearing seat together. When press-fitting, on the end face of the inner ring of the bearing, pad an assembly sleeve (copper or mild steel) made of soft metal material. The outer ring of the bearing is tightly fitted with the hole of the bearing seat, and the inner ring and the shaft are When the fit is loose, the bearing can be pressed into the bearing seat hole first.
At this time, the outer diameter of the assembly sleeve should be slightly smaller than the diameter of the seat hole. If the bearing ring is tightly fitted with the shaft and the seat hole, install the inner ring and the seat hole. The outer ring should be pressed into the shaft and the seat hole at the same time, and the structure of the assembly sleeve should be able to press the end faces of the inner ring and the outer ring of the bearing at the same time.
Deep groove ball bearing installation method 2: Heating fit: By heating the bearing or bearing seat, the tight fit is transformed into a loose fit by thermal expansion. It is a common and labor-saving installation method.
This method is suitable for large interference. For the installation of the bearing, put the bearing or separable bearing ring into the oil tank and heat it evenly at 80-100 ℃ before hot-loading, and then take it out of the oil and install it on the shaft as soon as possible. In order to prevent the end face of the inner ring and the shaft shoulder after cooling If the fit is not tight, the bearing can be axially tightened again after cooling.
When the outer ring of the bearing is tightly fitted with the light metal bearing seat, the hot-fitting method of heating the bearing seat can be used to avoid the mating surface from being scratched. When heating the bearing with the oil tank, there should be a mesh grid at a certain distance from the bottom of the box, or hang the bearing with a hook.
The bearing should not be placed on the bottom of the box to prevent heavy impurities from entering the bearing or uneven heating. There must be a thermometer in the oil tank. Strictly control the oil temperature not to exceed 100 ℃ to prevent the tempering effect and reduce the hardness of the ferrule.
Precautions for deep groove ball bearings
For deep groove ball bearings, the bearing load is too small during operation, which will cause sliding between the ball and the raceway, which will become the cause of scratches. This is especially true for large deep groove ball bearings with heavy ball and cage weights. In many cases, bearings will corrode.
There are many reasons for bearing corrosion. The most common factors in our daily life are the following:
1) Due to the poor sealing device, it is invaded by moisture, dirt, etc.;
2) Bearings are not used for a long time, beyond the rust prevention period, and lack of maintenance.
3) The metal surface roughness is large;
4) Contact with corrosive chemical medium, the bearing is not cleaned cleanly, the surface is stained with dirt, or the bearing is touched with sweaty hands. After the bearing is cleaned, it is not packaged or installed in time, and it is exposed to the air for a long time. contaminate;
5) Ambient temperature and humidity and contact with various environmental media; the rust inhibitor fails or the quality does not meet the requirements.
Deep groove ball bearing suffix meaning
CN: Common Group Radial Clearance; usually only used in mixture with the following letters to denote narrower or balance clearance ranges
H: Reduced clearance range, equivalent to the higher semi of the unique clearance range
L: Reduced clearance range, equivalent to the lower semi of the genuine clearance range
P: The stability clearance range, which is equivalent to the composition of the higher half of the original approval range and the lower half of the next set of clearance ranges. The above letters also apply to the meanings corresponding to the following clearance groups: C2, C3, C4, and C5, such as C2
C2: Radial clearance is smaller than ordinary group
C3: Radial clearance is larger than ordinary group
C4: Radial clearance is greater than C3
C5: Radial clearance is greater than C4
DB: Two single row deep groove ball bearings paired back-to-back
DF: Two single row deep groove ball bearings mated face to face
DT: Two single row deep groove ball bearings paired in tandem
E: Reinforced design
GJN: Polyurea based grease, NLGI consistency 2, temperature range -30 to +150 degrees (standard fill level)
GXN: Polyurea based grease, NLGI consistency 2, temperature range -40 to +150 degrees (standard fill level)
J: Stamped steel cage
LHT23: Lithium-based grease, NLGI consistency 2, temperature range -50 to +140 degrees (standard fill level)
LT: Lithium-based grease, NLGI consistency 2, temperature range -55 to +110 degrees (standard fill level)
LT10: Lithium-based grease, NLGI consistency 2, temperature range -50 to +90 degrees (standard fill level)
M: Machined brass cage, ball guided. Different designs and materials are marked with a number after M, such as M2
MA: Machined brass cage, outer ring guided
MB: Machined brass cage, inner ring guided
MT33: Lithium-based grease, NLGI consistency 3, temperature range -30 to +120 degrees (standard fill level)
MT47: Lithium-based grease, NLGI consistency 2, temperature range -30 to +110 degrees (standard fill level)
N: Outer ring with stop groove
NR: Outer ring with snap groove and snap ring
N1: There is a groove on the side of the outer ring (for use with a stopper to prevent the outer ring from turning)
P5: Dimensional and rotational accuracy to ISO tolerance class 5
P6: Dimensional and rotational accuracy to ISO tolerance class 6
P52: P5+C2
P62: P6+C2
P63: P6+C3
RS1: Nitrile butadiene rubber (NBR) contact seal with steel skeleton on one side
RSH: Nitrile butadiene rubber (NBR) contact seal with steel skeleton on one side
RSL: Nitrile butadiene rubber (NBR) low friction seal with steel skeleton on one side
RZ: Nitrile butadiene rubber (NBR) low friction seal with steel skeleton on one side
TH: Fiber-reinforced phenolic resin cage (card type)
TN: Injection-molded nylon cage
TN9: Injection molded glass fiber reinforced nylon 6,6 cage
VL0241: The outer surface of the outer ring is coated with aluminum oxide, and the insulation capacity is up to 1000VDC
VL2071: The outer surface of the inner ring is coated with aluminum oxide, and the insulation capacity is up to 1000VDC
WT: Polyurea based grease, NLGI consistency 2, temperature range -40 to +160 degrees (standard fill level)
Y: stamped copper cage
Z: One side with stamped steel dust cover
ZNR: Outer ring with retaining groove and retaining ring, with stamped steel dust cover on the other side of the retaining groove
2RS1: Nitrile butadiene rubber (NBR) contact seal with steel frame on both sides
2RSH: Nitrile butadiene rubber (NBR) contact seal with steel frame on both sides
2RSL: Nitrile-butadiene rubber (NBR) low-friction seals with steel frame on both sides
2RZ: Nitrile butadiene rubber (NBR) low friction seals with steel skeleton on both sides
2Z: stamped steel dust cover on both sides
2ZNR: outer ring with snap groove and snap ring, stamped steel dust caps on both sides
Common suffixes with ball notches:
C3: Radial clearance is larger than ordinary group
N: Outer ring with stop groove
NR: Outer ring with snap groove and snap ring
Z: One side with stamped steel dust cover
ZNR: Outer ring with retaining groove and retaining ring, with stamped steel dust cover on the other side of the retaining groove
2Z: stamped steel dust cover on both sides
2ZNR: outer ring with snap groove and snap ring, stamped steel dust caps on both sides
The meaning of stainless steel suffix:
R: Outer ring with flange
VT378: Non-toxic grease (incidental contact with food ingredients)
2RS1: Nitrile butadiene rubber (NBR) contact seal with steel frame on both sides
2Z: stamped steel dust cover on both sides
2ZR: stamped steel dust caps on both sides and flanged outer ring
