滚动轴承Rolling Bearings

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滚动轴承 Rolling Bearings
Rolling bearings is a collective name for
shaft support bearings that have
revolving elements between a moving
and a stationary ring. This is in contrast
to plain bearings.
工作时,由滚动体在内外圈的滚
道上进行滚动摩擦,并支承轴的部件
,叫滚动轴承。
滚动轴承由外圈、内圈、滚动体
和保持架四个部分组成。
1
点、线接触 Point and Line contact
With a ball bearing, the load is transmitted to
the runway through the balls and a very small
surface. This is called a point contact. The bearing
capacity is therefore less than that of a roller
bearing, where the load is transmitted through a line
contact to the runways.
球轴承中,在载荷的作用下,滚动
体(球)与滚道的接触面几乎为一个点
,称为点接触。
而接触面为一条线,称为线接触。
点接触轴承承载能力不如线接触轴
承。
2
滚动轴承的类型 Radial and Axial Bearings
Rolling bearings are subdivided into two main groups, namely

Radial rolling bearings.

Axial rolling bearings
-
Radial bearings mainly serve for taking up a load radially, i.e.
perpendicular to the shaft. Axial bearings mainly serve for a load
in the axial direction of the shaft. Certain types of bearing can
take a combined load.
向心轴承。主要承受径向载荷。
推力轴承。只能承受轴向载荷。
向心推力轴承。能同时承受径向载荷和轴向载荷的轴承。
3
滚动轴承和滑动轴承的比较
Rolling bearings compared to a plain bearings
4
滚动轴承的优点
Advantages of rolling bearings to plain bearings
1. 起动灵敏。 Small starting moment
2. 摩擦系数小。 Low friction at all speeds
3. 效率高。Low consumption of energy
4. 旋转精度高。High reliability
5. 轴向尺寸小。 Little width
6. 润滑简便。 Long lubrication intervals
7. 润滑剂消耗最小。 Minimum consumption of lubricant
8. 易于更换。Easy to replace
9. 标准件。 Standardised dimensions
5
滚动轴承的结构及名称
Definitions
6
滚动轴承的类型
Bearing types
• 深沟球轴承
• 调心球轴承
• Deep groove ball bearing
• Self aligning ball bearing
7
滚动轴承的类型
Bearing types
• 角接触球轴承
• 双列角接触球轴承
• Angular contact bearing
• Two row angular contact bearing
8
滚动轴承的类型
Bearing types
• 调心滚子轴承
• 圆柱滚子轴承
• Spherical roller bearing
• Cylindrical bearing
9
滚动轴承的类型
Bearing types
• 滚针轴承
• 推力球轴承
• Needle bearing
• Thrust ball bearing
10
滚动轴承的类型
Bearing types
• 推力圆柱滚子轴承
• 推力调心滚子轴承
• Cylindrical thrust bearing
• Spherical roller thrust bearing
11
滚动轴承的代号
Rolling bearing coding
12
例子
An example
22320 EK C3
The significance of the above bearing code is as follows:
2 =two-row barrel shape bearing 调心滚子轴承
23=dimension series 尺寸系列代号,2为宽度系列代
号,3为直径系列代号
20=diameter bore
内径代号
x5=20x5=100 mm
E=altered internal construction 内部结构改变
K=conical bore 1:12 内孔锥度为1:12
C3= radial clearance larger than normal. 游隙代号
13
轴承装配的预防措施
Precautionary measures with the assembly of bearings
Inspect the parts of the bearing set-up and remove
all burrs(毛刺). Clean the shaft and check the
seats on diameter tolerance and dimensional
accuracy. Inspect the seals and replace them if they
are damaged. A rubber seal must always be
replaced.
14
轴承装配的预防措施
Precautionary measures with the assembly of bearings
Unpack new bearings just before the
assembly. They must remain protected
against dirt as long as possible. The
preserving(保留) agent must not be
removed, except from the bearing bore
and the outer surface of the outer ring.
Wash these surfaces with an oilbased
solvent and dry them. Use a lint-free
cloth. Large bearings are often
protected by a relatively thick layer of
hot greasy preserving agent, in which
the bearing is immersed(陷入). This
layer must be removed by washing
before assembly.
15
轴承的清洗方法
Cleaning methods of bears
There are two methods to clean bearings: cold and hot.
With cold cleaning, the bearing is washed with an oilbased solvent.
Always use clean liquid and tools, with the first washing stage being
done in one tank and the last rinsing(冲洗) stage in another
tank. Dry the bearing and smear(涂上) it immediately after
drying with grease or oil. Protect it against dirt until assembly.
With hot cleaning, use a thin, clean oil with a flash point of at least
250 °C. The oil must be heated to about 120 °C. Hot cleaning is
mostly very efficient, and the remaining oil offers a temporary(临
时的) protection against corrosion(侵蚀).
16
轴承的安排
Bearing arrangement
17
滚动轴承装配的方法
assembly and/or disassembly method
1. 机械压入法。Mechanical method
2. 液压法。 Hydraulic method
3. 压油法。Pressure oil method
4. 温差法。 Thermal method
The following division is made with regard to bearing size:
Small bearings:
bore < 80 mm
Medium bearings:
bore 80 to 200 mm
- Large bearings:
bore > 200 mm.
18
圆柱孔轴承的装配
Assembly of bearings with cylindrical bore
不能直接敲打轴承的内外圈、保持架和
滚动体。
During assembly, never strike directly against the
bearing rings, cage or the rolling elements.
装配的压力应直接加在待配合的套圈端
面上,决不能通过滚动体传递压力。
Never exert force on the one ring to assemble the
other. The force will then be transmitted to the
rolling elements.
19
圆柱孔轴承的装配
Assembly of bearings with a cylindrical bore
20
机械方法
Mechanical method(cold assembly)
21
用温差法装配
Thermal method(hot assembly)
The temperature difference between the
bearing and the seat depends on the tightness
of the fit and the bearing size. Usually, a
bearing temperature of 80 to 90 °C above
that of the shaft is sufficient for assembly. The
bearing may never be heated above 125 °C,
because there is a chance that the material
properties will change.
During assembly, use clean protective gloves(手套) to handle the bearing. Slide
the bearing over the shaft as far as the contact face and keep it pressed against this
until the bearing is fixed.
22
用温差法装配
Thermal method(hot assembly)
Depending on the type of bearing to be assembled, there
are different heating methods applicable, i.e.:




Induction heaters 感应加热器
Electrical heating plates 电子加热盘
Heating cabinets 加热箱
Oil baths. 油浴
23
用温差法装配
Thermal method(hot assembly)
Bearings must never be heated in
an open fire because this will
cause stresses in the bearing
material.
24
用温差法装配
Thermal method(hot assembly)
• 感应加热器
• 电加热盘
• Induction heater
• Electrical heating plate
25
用温差法装配
Thermal method(hot assembly)
Heating cabinet
Here, the bearings are heated in
an electrical heating cabinet, in
which a blower(送风机) is fitted.
The advantages of these cabinets
are that a large number of
bearings can be heated at the
same time and that the bearings
can be kept at the same
temperature for a long time.
Oil bath
When heating a bearing with the aid of
an oil bath, we use a tray (盘)filled
with oil that is placed on a heating
element. Because the bearing may
never come into contact with the tray,
the tray contains a perforated(打孔)
plate on which the bearing lies. Of
course, it is also possible to hang the
bearing on a bracket(支架) in the oil.
It is necessary to watch the
temperature of the oil bath carefully.
26
圆柱孔轴承的拆卸
Disassembly of bearings on a cylindrical seating
With the disassembly of bearings with a
cylindrical bore, the cold disassembly method
should be subdivided into:
- Mechanical method 机械的方法
- Hydraulic method 液压的方法
- Pressure oil method. 压油的方法
27
圆柱孔轴承的拆卸
Disassembly of bearings on a cylindrical seating
Mechanical method
Small and medium size bearings with a tight fit on the shaft can be
disassembled with the aid of a normal puller.
Puller on the inner ring
Turning of the bearing during
disassembly
28
圆柱孔轴承的拆卸
Disassembly of bearings on a cylindrical seating
Disassembly via the outer ring
29
圆柱孔轴承的拆卸
Disassembly of bearings on a cylindrical seating
Disassembly by means of a hydraulic puller
Tight fit on inner and outer rings
30
Disassembly by means of pressure oil method
圆柱孔轴承的拆卸
Disassembly of bearings on a cylindrical seating
Thermal method
Disassembly by means of heating is a suitable method to remove the inner rings
of cylinder bearings. Here, special tools can be applied, such as aluminium rings.
Heating by means of aluminium
ring
Heating by means of
induction heater
31
圆柱孔轴承的装配和拆卸
Cylindrical seating
32
圆锥孔轴承的装配
Assembly of bearings with tapered bore
With the cold method, however, another distinction(区别) must also be
made:
- Mechanical method
- Hydraulic method
- Oil pressure method.
Small bearings are usually assembled cold with the aid of a mounting bush
and a hammer or a locking nut and a spanner.
Larger bearings can be assembled more easily by using a hydraulic nut
and/or the pressure oil method.
In certain cases, the bearing can be assembled by means of the thermal
method.
33
机械的方法
Mechanical method (cold method)
Assembly with the aid of the nut and
spanner
Assembly with the aid of an
impact bush
The use of a impact spanner
34
用液压螺母装配轴承
Hydraulic method
Bearings with a bore of more than
50mm can be assembled easily and
reliably(可靠的) with the aid of a
hydraulic nut.
35
压油的方法
Pressure oil method
This is a method for medium
size and large bearings. Here,
oil is injected under high
pressure between the surfaces
of the bearing and the seat,
until both are completely
separated. This reduces the
friction to practically zero.
36
热配法
Hot assembly
When, for one reason or another, the pressure oil
method or a hydraulic nut cannot be used, the
alternative(可选择的方法) is to heat the bearing.
This can be done with the aid of an induction heater,
heating cabinet(箱) or an oil bath(油浴).
37
Assembly against a collar
Slide the cold bearing on the shaft until it makes good contact
with its seat. Measure the distance between the inner ring and
the collar(套). This must be reduced by the axial driving
on; for this, consult(参考) the tables.
38
Assembly on a shaft without collar
Follow the procedure(程序)
described above, but measure with
respect to a reference(参考)
plane instead of to a collar.
Increase or reduce this dimension
by the length of driving up to obtain
the “assembly distance”. Measure
the distance while the bearing is
slid onto the tapered seat. Keep the
bearing in place until it clamps.
Place the locking nut and check the
clearance when the bearing has
cooled down.
39
用紧定套安装轴承
Mounting a bearing with a adapter sleeve
40
用紧定套安装轴承
Mounting a bearing with a adapter sleeve
Assembly of a self-adjusting ball bearing on a drawing sleeve
41
用紧定套安装轴承
Mounting a bearing with a adapter sleeve
Assembly of a two-row barrel shape bearing on a drawing sleeve
42
用紧定套安装轴承
Mounting a bearing with a adapter sleeve
43
用紧定套安装轴承
Mounting a bearing with a adapter sleeve
An alternative method is to heat the bearing.
44
用退卸套安装轴承
Mounting a bearing with a adapter sleeve
Assembly on a pressing sleeve(退卸套)
45
用退卸套安装轴承
Mounting a bearing with a adapter sleeve
Cold assembly
46
用退卸套安装轴承
Mounting a bearing with a adapter sleeve
Use of a hydraulic nut or pressure oil method
47
用液压螺母装配轴承
Assembly of bearings with hydraulic nut
48
用液压螺母装配轴承
Assembly of bearings with hydraulic nut
49
用液压螺母装配轴承
Assembly of bearings with hydraulic nut
50
用液压螺母装配轴承
Assembly of bearings with hydraulic nut
51
用液压螺母装配轴承
Assembly of bearings with hydraulic nut
52
圆锥孔轴承的装配和拆卸
Tapered seating
53
紧定套 Adapter sleeve
54
退卸套
Withdrawal sleeve
55
圆锥孔轴承的拆卸
Disassembly of bearings with tapered bore on a tapered axle journal
56
圆锥孔轴承的拆卸
Disassembly of bearings with tapered bore on a drawing or pressing sleeve
57
圆锥孔轴承的拆卸
Disassembly of bearings with tapered bore on a drawing or pressing sleeve
58
圆锥孔轴承的拆卸
Disassembly of bearings with tapered bore on a drawing or pressing sleeve
59
圆锥孔轴承的拆卸
Disassembly of bearings with tapered bore on a drawing or pressing sleeve
60
圆锥孔轴承的拆卸
Disassembly of bearings with tapered bore on a drawing or pressing sleeve
61
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