·Development and Reform Commission requested to guide the release of community parking fee prices

On the 4th, the reporter learned from the National Development and Reform Commission that since late November 2014, the National Development and Reform Commission and the relevant departments have successively issued eight documents, liberalized the prices of 24 commodities and services, and decentralized one pricing authority. This includes the liberalization of tobacco leaf purchase prices, which also means that there are no government pricing projects in China's agricultural products sector, all of which are liberalized by the market. In addition, the National Development and Reform Commission also requested to guide the local government to release the price of nine services such as non-protected housing properties and residential community parking fees.
Let go of the tobacco leaf purchase price. The National Development and Reform Commission and the State Tobacco Monopoly Bureau issued a notice to release the purchase price of tobacco, burley, oriental tobacco and other varieties and grades of tobacco.
Some agricultural products still need the government to support the director of the Chinese Academy of Agricultural Sciences, the director of the Agricultural Economics Institute, Qin Fu said that China's current government regulation price has not completely withdrawn from the historical stage, such as the state's minimum purchase price policy for rice, wheat, corn, Rapeseed has implemented a temporary storage and storage policy, and carried out pilot reforms of target price subsidies for cotton and soybeans, and established a plan for the regulation of cyclical fluctuations in market prices for live pigs.
“The way the government relies on the bottom is not free to change.” The target price of cotton and soybeans is a pilot that started last year. Although the prices of the two agricultural products are formed by both the market supply and demand, once the market price is lower than the target. The price, the government still plays this role mechanism, using the target price to regulate. The combination of market regulation and government regulation has prevented large fluctuations in the prices of major agricultural products and protected the interests of farmers.
The domestic civil aviation freight price and some civil aviation passenger transport prices will be released. Fully liberalize the price of goods transported on domestic routes of civil aviation; release the fare of short-haul routes between 101 adjacent provinces that compete with the main modes of transportation on the ground; and continue to retain the domestic civil passenger fares that carry out government-guided prices. Air transportation enterprises independently formulate and adjust the base fares in accordance with the rules established by the state.
According to the relevant person in charge of the Civil Aviation Administration, the current civil aviation domestic route freight rate and passenger fare are managed by the Civil Aviation Administration in conjunction with the National Development and Reform Commission, mainly implementing the government guidance price, short-haul routes in the province, and some The ground transportation mode forms a competitive cross-provincial route passenger fare to implement market regulation. A market with more competition is an important prerequisite for liberalizing price controls.
Li Xiaojin, a professor at the School of Economics and Management of Civil Aviation University of China, said that liberalizing price controls will give airlines more independent pricing power for different time periods and off-season seasons, enabling airlines to increase attendance and make full use of resources while also giving consumers more Choose more to maximize consumer benefits.
Guide the place to release the price of 9 items of goods and services. Release of railway passenger and cargo transportation extension service charges, postal extension service charges and accountant services, tax accountant services, asset assessment services, real estate brokerage services, non-guaranteed housing property services, residential community parking services, some lawyer services, etc. service fee.
Release the market competition, the industry responsible for the National Development and Reform Commission, the relevant person in charge said that with the development and improvement of China's market economy, the marketization of relevant service areas has developed rapidly, such as land price assessment, real estate price assessment and other fields, national related assets There are about 20,000 price appraisal institutions with more than 300,000 employees. The market is more competitive and has the conditions for liberalization.
Another example is property services. At present, there are 71,000 property service enterprises in the country, with more than 6 million employees, and the service supply is sufficient. In addition, the price of commodity housing is formed by market competition. The self-management and active rights protection mechanism of the owners is gradually established and improved. For non-guaranteed housing. The property service and residential community parking service charges can be adopted by the owners' committee in the form of open tendering. Compared with the quality comparison, the property service enterprises with good service quality and low charging standards are selected.
Other projects released four rail transport prices with competitive conditions. The National Development and Reform Commission issued a notice to liberalize the freight rate of railway bulk cargo and railway parcels, as well as the freight rates of the new railways and the passenger fares of passenger dedicated lines.
Release the port's competitive service charges. The Ministry of Transport and the National Development and Reform Commission jointly issued a notice to release the labor charges such as container handling and international passenger terminal operations, as well as the charges for service such as ship garbage disposal and water supply. In addition to the comprehensive calculation, the owner and passengers may not be charged separately.
Let go of the ex-factory price of civilian explosive equipment. The National Development and Reform Commission, the Ministry of Industry and Information Technology, and the Ministry of Public Security jointly issued a notice to release the ex-factory price of civil explosive equipment and cancel the management of the circulation rate of civil explosive equipment. Relevant departments will strengthen post-event supervision in matters such as safety supervision, social public safety control, and price behavior supervision according to their duties.
Release the price of 7 professional services. The National Development and Reform Commission issued a notice to open up foreign consular certification visas, document key services, customs statistics and data development, trademark registration and other certifications, foreign-related (Taiwan) economic and trade dispute mediation, land price assessment, real estate price assessment, etc. 7 The fees for professional services provide consumers with more choices and encourage social capital to enter relevant fields.

Angular contact Ball Bearings

 

Angular Contact Ball Bearing has high limit rotational speed, they can carry radial load and axial load simultaneously, they can also withstand purely radial load. The axial load carrying capacity depends on the magnitude of contact angle and increases with increasing contact angle.

Structures

1. Non-separable angular contact ball bearings

This inner ring and outer ring of this type of bearings cannot be separated and comprises following structures:

Contact angle α=15°      counter bore on outer ring,7000Ctype

Contact angle α=25°      counter bore on outer ring,7000ACtype

Contact angle α=40°      counter bore on outer ring, 7000B type

2. Four-point contact ball bearings

This type of bearings is separable bearings. Whereof, QJ0000 type has two-piece inner ring and QJF0000 type has two-piece outer ring. Their contact angles are same as 35°.When received no load or pure radial load, the steel balls of the Ball Bearing contact with the four points of the rings. When it is received a pure axial load, the steel balls perform a two-point contact with the ring. In addition, besides the axial load from both directions, this kind of bearing can take torque-load as well.

3. Double row angular contact ball bearings

This kind of bearings can accommodate radial loads as well as axial loads acting in both directions; they can also take loading moment. They can restrain the axial displacement from both directions of the shaft or housing; the contact angle is 30° (or 40°)

Permissible tilt angle

There is only a little inclination between the inner ring and outer ring of angular contact bearings, the permissible tilt angle varies according to the internal clearance when the bearings are operating, the bearing dimensions, internal design, force and loading moment received by the bearings. The value of the maximum permissible tilt angle should be able to ensure that no much extra stress to be generated inside the bearings.

The tilt angle existing between the inner ring and outer ring will influence the bearing service life. Meanwhile, the running accuracy is decreased down and noise increased.

Tolerance and clearance

The tolerances of general angular contact bearings are class normal P0, class P5 and P6. Class P4 and P2 are applicable to machine tool spindles and bearing amount in pairs.

Clearance of single row angular contact bearing is decided by the contact angle, which is guaranteed by manufacturing.

Axial clearance of Four-point contact ball bearings is listed in table 1.

Cage material

Generally, the cage of angular contact bearing is pressed cage of steel sheet or brass cage, and it is solid brass cage for two row angular contact bearing.

Dynamic equivalent radial load

Single-row angular contact ball bearings with a contact angle of 15°

Single bearing or bearing in pairs(7000 C.7000 C/DT)

Fa/Fr≤e         Pr=Fr 

Fa/Fr>e          Pr=0.44Fr+YFa

Back-to-back and face to face arrangements(7000 C/DB.7000 C/DF)

Fa/Fr≤e         Pr=Fr+Y1Fa       

Fa/Fr>e          Pr=0.72Fr+Y2Fa    

Single-row angler contact ball bearings with a contact angle of 25°

Single bearing or bearing in pairs(7000 AC.7000 AC/DT)

Fa/Fr≤0.68      Pr=Fr             

Fa/Fr>0.68       Pr=0.41Fr+0.87Fa   

Back-to-back and face to face arrangements(7000 AC/DB.7000 AC/DF)

Fa/Fr≤0.68      Pr=Fr+0.92Fa       

Fa/Fr>0.68       Pr=0.67Fr+1.41Fa    

Single-row angular contact ball bearings with a contact angle of 40°

Single bearing or bearing in pairs (7000 B.7000 B/DT)

Fa/Fr≤1.14      Pr=Fr             

Fa/Fr>1.14       Pr=0.35Fr+0.57Fa   

Back-to-back and face to face arrangements(7000 B/DB.7000 B/DF)

Fa/Fr≤1.14      Pr=Fr+0.55Fa      

Fa/Fr>1.14       Pr=0.57Fr+0.93Fa   

Four point contact ball bearings with a contact angle of 35°

Fa/Fr≤0.95      Pr=Fr+0.66Fa      

Fa/Fr>0.95       Pr=0.6Fr+1.07Fa    

Double-row angular contact ball bearings with a contact angle of 45°

Fa/Fr≤1.34      Pr=Fr+0.47Fa      

Fa/Fr>1.34       Pr=0.54Fr+0.81Fa   

Static equivalent radial load

Single-row angular contact ball bearings with a contact angle of 15°

For single bearing or bearing in pairs(7000 C.7000 C/DT)

 

P0r=0.5Fr+0.46Fa   

P0r<Fr  P0r=Fr

For back-to-back and face-to-face arrangements (7000 C/DB.7000 C/DF)

P0r=Fr+0.92Fa

Single-row angular contact ball bearings with contact angle of 25°

For single bearing or bearing in pairs (7000 AC.7000 AC/DT)

P0r=0.5Fr+0.38Fa  

when P0r<Fr  let P0r=Fr

For two bearings in back-to-back and face-to-face arrangements

P0r=Fr+0.76Fa

Single-row angular contact ball bearings with contact angle of 40°

For single bearing or bearing in pairs

P0r=0.5Fr+0.26Fa   

when P0r<Fr  let P0r=Fr

For two bearings in back-to-back and face-to-face arrangements

P0r=Fr+0.52Fa

Four point contact ball bearings

P0r=Fr+0.58Fa

Double-row angular contact ball bearings with contact angle of 45°

P0r=Fr+0.44Fa

Fr  Actual radial load of the bearing.

F Axial load of the bearing

The values of e .Y .Y1 .Y2  see Table 2.

Table 1   Axial internal clearance of four point contact ball bearings

                                        μm

Nominal bore diameter  d

mm

C2 clearance

Standard clearance

C3

clearance

C4

clearance

Over

To

Min

Max

Min

Max

Over

To

Min

Max

10

18

40

 

60

80

100

 

140

180

220

 

260

18

40

60

 

80

100

140

 

180

200

260

 

300

15

26

36

 

46

56

66

 

76

96

115

 

135

55

66

86

 

96

116

136

 

156

176

195

 

215

45

56

76

 

86

96

116

 

136

156

175

 

195

85

106

126

 

136

156

176

 

196

216

235

 

275

75

96

116

 

126

135

156

 

176

196

215

 

255

115

146

166

 

176

196

216

 

236

256

295

 

335

105

136

156

 

166

176

196

 

216

236

275

 

295

145

186

206

 

216

236

256

 

276

296

335

 

355

 

Table 2   Calculate Coefficient

                           Î¼m

e

Y

Y1

Y2

0.172

0.345

0.689

1.03

1.38

2.07

3.45

5.17

6.89

0.38

0.4

0.43

0.46

0.47

0.5

0.55

0.56

0.56

1.47

1.4

1.3

1.23

1.19

1.12

1.02

1

1

1.65

1.57

1.46

1.38

1.34

1.26

1.14

1.12

1.12

2.39

2.28

2.11

2

1.93

1.82

1.66

1.63

1.63

Dw is the diameter of the rolling element

Angular Contact Ball Bearing

Machined Cage Angular Contact Ball Bearing,Pressed Cage Angular Contact Ball Bearing,One Row Angular Contact Ball Bearing,Two Row Angular Contact Ball Bearing

Xibei Bearing Co.,Ltd. , http://www.nxzjck.com