Types Of Ceramic Bearings
Types Of Ceramic Bearings
2021年12月9日
Difference Between Sliding Bearing And Rolling Bearing
Difference Between Sliding Bearing And Rolling Bearing
2021年12月9日

Difference Between Pitch Bearing And Yaw Bearing

 

1. Anti corrosion treatment of pitch bearing and yaw bearing surface

To meet the anti-corrosion requirements of alignment yaw bearing, we choose arc spraying long-term anti-corrosion process It uses special arc spraying equipment to melt, atomize and spray corrosion-resistant metal (pure aluminum or zinc) to the surface of the workpiece to form a metal arc spraying layer; Then close it with corrosion-resistant coating with strong permeability; It constitutes arc spraying long-term anti-corrosion composite coating Its technical features are as follows: ① long anti-corrosion life; Up to more than 20 years, ② high coating contact force, ③ good coating quality The process path: preparation of semi-finished products of inner and outer rings of bearings → pre sanitation → pre protection of workpieces → sand blasting → arc spraying → closing disposal; It is described as follows

 
1) Preparation of semi-finished products of bearing inner and outer rings

In order to ensure that the yaw bearing has high appearance quality; Organize the anti-corrosion spraying process after all machining; The sprayed bearing parts shall be directly warehoused after the completion of the device; Ensure that the anti-corrosion coating is not scratched

2) Pre hygiene

Degreasing with organic solvent; There may be oil stain on the surface of bearing semi-finished products after machining; In order to ensure the spraying quality, it is necessary to organize the sanitary process before spraying

3) Workpiece pre guarantee

Before sand blasting and spraying, the arc raceway, threaded hole and the appearance that does not need spraying shall be protected by special appearance pre protection tooling

Difference Between Pitch Bearing And Yaw Bearing
 
4) Sandblasting

Roughen the surface of the inner and outer rings of the bearing; Add the contact surface between the coating and the workpiece; Make the surface of the workpiece more activated; Improve coating contact strength.

5) arc spraying

Arc spraying (pure aluminum or zinc) equipment mainly includes DC power supply, spraying gun, air compressor and air filter; It mainly controls arc voltage, current, wire feeding speed, compressed air pressure, spraying interval and other parameters

6) Close disposal

Because there are pores in the sprayed coating; Therefore, it is necessary to close it; Add corrosion resistance

After spraying and installation, the main exposed machined surfaces of yaw bearing include gear surface, device thread surface and arc raceway surface The first two are coated with antirust oil after the device; The latter is applied with lubricating grease when installing the device; The inner packaging of products shall be closed and surrounded with plastic film; The outer layer is surrounded by plastic woven belt; Satisfied with rust protection requirements

 

2. Damping torque

The composition mechanism of pitch bearing and yaw bearing is different

There are two origins of the rear damping torque of the yaw bearing device: one is the conflict resistance of the raceway; The second is the conflict resistance between the sealing strip and the sealing surface The latter is usually constant under the same processing conditions; Therefore, the magnitude of the rear damping torque of yaw bearing device mainly depends on the former. The friction moment of some raceways during reverse rotation mainly depends on the size of the bearing gap Yaw bearing requires zero clearance or negative clearance; The number of negative voids is determined by the collision damping moment behind the device Therefore, the magnitude of the collision damping torque after the device basically depends on the device clearance value of the yaw bearing;

 

The composition of this value mainly depends on four links: finish turning scale before raceway quenching, raceway surface quenching, grinding scale after raceway quenching and scale selection of rollover body. The stress of wind power bearing (yaw bearing and pitch bearing) is complex; And the impact and oscillation of the bearing are relatively large; Therefore; The required bearing can accept impact; It can also accept large load The service life of main engine of wind turbine generator needs 20 years; The cost of bearing device is large; Therefore, the service life of yaw and pitch bearings needs to reach 20 years. Wind turbines can operate in extremely cold areas; The ambient temperature is as low as – 400C; The operating temperature of the bearing is about – 200C; It is necessary that the bearing can accept large impact load at low temperature

 

Yaw and pitch bearings have special requirements in clearance Relative to yaw bearing; The impact load of pitch bearing is relatively large; The wind blew on the leaves and caused a great sensation; Therefore, the clearance of pitch bearing should be zero clearance or slightly negative clearance; In this way, the fretting wear of the bearing can be reduced in case of shock The yaw bearing needs a small clearance value. Field operation of wind turbine equipment; And some of the yaw and pitch bearings are exposed to the outside; Will be subject to air pollution; High humidity environment will also corrode the bearing matrix; Therefore; The exposed parts of yaw and pitch bearings shall be subject to external anti-corrosion treatment