Comprehensive Knowledge of Deep Groove Ball Bearings!
Deep groove ball bearings (GB/T 276-1994), formerly known as single row radial ball bearings, are one of the most widely used rolling bearings.
Deep groove ball bearings (GB/T 276-1994), formerly known as single row radial ball bearings, are one of the most widely used rolling bearings. Its characteristics are small friction resistance, high speed, can be used to bear radial load or radial and axial simultaneous action of the combined load on the machine, can also be used to bear axial load on the machine, such as small power motors, cars and tractors gearboxes, machine tool gearboxes, general machines, tools, etc.
Deep groove ball bearing is the most common type of rolling bearing.
The basic type of Wafer Butterfly Valve consists of an outer ring, an inner ring, a set of steel balls and a set of cage. Deep groove ball bearing type has single row and double row two, deep groove ball structure is also divided into sealed and open two kinds of structure, open refers to the bearing without sealing structure, sealed deep groove ball is divided into dustproof seal and oilproof seal. Dustproof seal cover material for steel plate stamping, only play a simple prevent dust into the bearing raceway. The oil-proof type is contact oil seal, which can effectively stop the grease inside the bearing from spilling out.
Single row deep groove ball bearing type code for 6, double row deep groove ball bearing code for 4. Its structure is simple, easy to use, is the most common production, the most widely used type of bearings.
Deep groove ball bearings are mainly used to bear radial load, but also commonly used to bear radial and axial composite load. Especially the mechanical equipment speed is very high, should not use thrust bearing, the bearing can be used to withstand two-way pure axial load, and no maintenance during the work, is a lower price, a widely used bearing.
Deep groove ball bearing models are
â— Deep groove ball bearings (60000 type).
â— Deep groove ball bearings with stop groove on the outer ring (60000N type).
â— Deep groove ball bearings with dust cover on one side and stop groove on the other side (60000-ZN type);
◠Deep groove ball bearing with dust cover on both sides and stop groove on the outer ring (60000-2ZN type); ⑤ Deep groove ball bearing with dust cover on one side and stop groove on the outer ring (60000-ZN type)
â— Deep groove ball bearings with dust cover on one side (60000Z type).
â— Deep groove ball bearing with dust cover on both sides (60000-2Z type).
â— Deep groove ball bearings with seals on one side (60000-LS type, 60000-RZ type).
â— Deep groove ball bearings with seals on both sides (60000-2LS type, 60000-2RZ type).
â— Flanged outer ring deep groove ball bearings (type F60000);
â— Flanged outer ring deep groove ball bearing with dust cover on one side (type F60000-Z); â‘© Flanged outer ring deep groove ball bearing with dust cover on one side (type F60000-Z)
â— Flanged outer ring deep groove ball bearing with dust cover on both sides (F60000-2Z type), 11 types in total.
According to the size of deep groove ball bearings can be divided into
(1) Miniature bearings ---- with a nominal outside diameter size range of 26mm or less;
(2) Small bearings ---- with nominal outer diameter size range of 28-55mm;
(3) Small and medium-sized bearings ---- with nominal outer diameter size range of 60-115mm;
(4) Medium and large size bearings ---- with nominal outer diameter size range of 120-190mm
(5) Large size bearings ---- with nominal outer diameter size range of 200-430mm;
(6) Extra large bearings ---- with nominal outer diameter size range of 440mm or more.
Deep groove ball bearings can be used in gearboxes, instruments, motors, household appliances, internal combustion engines, transportation vehicles, agricultural machinery, construction machinery, engineering machinery, roller skates, yo-yo balls, etc.
Clearance
The radial clearance of bearing is divided into original clearance, installation clearance and working clearance. Usually, the original radial clearance of the bearing is larger than the clearance of the bearing at work. Clearance is an important technical parameter of the bearing, which directly affects the load distribution, vibration, noise, friction, service life and mechanical movement accuracy and other technical performance of the bearing. Strictly speaking, the dynamic load rating of the bearing is with the size of the clearance and change. The rated load listed in the product sample (C and C0) is the load value when the working clearance is zero. The clearance is too large, will cause the bearing internal bearing area reduce, rolling contact surface stress increase, bearing movement accuracy decline, vibration and noise increase, bearing service life shorten: such as clearance is too small, will cause heat heating, even will lead to bearing in the operation of the "bite dead" phenomenon. Therefore, according to the type of bearing and working conditions to choose different levels of bearing clearance is very important.
Standard deep groove ball bearing has C2, standard (CN), C3, C4 and C5 level internal clearance, all with GB4604 in line.
Cage
Deep groove ball bearings generally use steel plate stamping cage or brass solid cage. When the outer diameter is less than 400 mm, the use of steel plate stamping cage does not add the rear code, when the outer diameter is greater than 400 mm, more brass entity cage does not add the rear code.
Rolling bearing code and method of expression
Rolling bearing code is a letter plus numbers to indicate the bearing structure, size, tolerance level, technical performance and other characteristics of the product symbol. The national standard GB/T272-93 provides the bearing code consists of three parts: the front code, the basic code, the rear code.
The basic code is the basis of the bearing code. Front code and rear code are bearing code supplement, only in case of special requirements for bearing structure, shape, material, tolerance level, technical requirements, etc. to use.
Specific code meaning.
1. a：Basic code
The basic code indicates the basic type, structure and size of the bearing. It is composed of bearing type code, size series code, bore code.
(1) a1: bearing type code, with numbers or letters to indicate the different types of bearings.
(2) a2: size series code, composed of two digits.
The first digit represents the width series (radial bearing) or height series (thrust bearing), the next digit represents the diameter series. Size series represents the same inner diameter bearing can have different outer diameter, and the same outer diameter has different width (or height).
(3) a3: inner diameter code, said the size of the nominal inner diameter of the bearing, expressed in numbers.
2. specific examples.
(1) bearing 23224
Description: 2-type code, spherical roller bearings; 32-size series code; 24-bore code, d = 120mm;
2）Bearing 6208-2Z/P6
Description: 6-Type code, deep groove ball bearing; 2-Dimension series code; 08-Inner diameter code, d=40mm.
2Z-bearing two end face with dust cover; P6-tolerance level in line with the standard provisions of grade 6
Inner diameter calculation
1. bearing bore with the basic code from the right of the first two digits. The common inner diameter d = 20 ~ 480mm bearing bore is generally a multiple of 5, the two digits indicate the bearing bore size by 5 divided by the quotient, such as 04 said d = 20mm; 12 said d = 60mm and so on.
2. For the inner diameter of 10mm, 12mm, 15mm and 17mm bearings, inner diameter code for 00, 01, 02 and 03. For the inner diameter of less than 10mm and more than 500mm bearings, the inner diameter of the method is otherwise specified, see GB/T272-93.
Precision of deep groove ball bearings
It is divided into dimensional accuracy and rotational accuracy, and the accuracy level can be divided into five levels: P0, P6, P5, P4 and P2, which are improved from P0 level. Non-special purpose use P0 level deep groove ball bearing is enough, for some specific conditions or occasions, need to use P5 level or more high precision bearings.
Deep groove ball bearing size accuracy and shaft and shell installation, generally refers to
1. The permissible deviation of bearing inner diameter, outer diameter, width and assembly width.
2. The permissible limit value of chamfer size.
3. the width of the permissible amount of change.
Deep groove ball bearing rotation accuracy and bearing rotating body runout related to:
1. the inner ring and outer ring allowable radial runout and axial runout.
2. the inner circle allowed transverse runout.
3. the allowable variation of the outer diameter surface tilt.