A、ZZ - Dust cover seals on both sides of the bearing

Use Environment：Ordinary motor, dust-proof working environment。

Advantage：Low cost, Low starting torque, and the high temperature and low temperature working conditions can be universal.

Disadvantage：The sealing gap is large (generally above 0.4mm), and the dust resistance is low.

B、RZ - Sealing with a skeleton rubber cover on one side of the bearing (non-contact type) /// 2RZ - Sealing with skeleton rubber cover on both sides of the bearing (non-contact type)

Use Environment：Motor etc.

Advantage：

1.The two sealing lips do not contact the bearing, the starting torque is low, and the heat generation is small;
2.The manufacturing accuracy of the sealing ring and the sealing labyrinth groove is low, and the cost is relatively low;
3.Due to the use of the labyrinth seal structure , Has a good dustproof effect。

Disadvantage：The sealing gap is MAX 0.2mm, and it has no resistance to dust, muddy water and water vapor.

C、RS - Sealing with a skeleton rubber cover on one side of the bearing (contact type)///2RS-Sealing with skeleton rubber cover on both sides of the bearing (contact type)

Use Environment：Motor, water pump, automobile tensioner, etc.

Advantage：

1.The main lip is in axial contact with the labyrinth seal groove, and the starting torque and heat generation are slightly increased;
2.Because the main lip is axially contacted and sealed, and the two secondary lips are sealed with radial gaps, it has a good dust-proof effect.

Disadvantage：

1.High requirements on the shape of the sealing groove and sealing ring;
2.No waterproof effect.

D、RSW - Heavy contact rubber cover seal

Use Environment：Automobile tensioner , automobile condensing fan, etc.

Advantage：

1.Three-lip seal, optimized design of the main lip angle and axial interference to prevent excessive starting torque;
2.The extended first secondary lip can form a small gap seal to prevent lubrication leakage and water vapor from entering;
3.The joint cooperation of the two auxiliary lips realizes the combined effect of radial seal and axial seal, and at the same time extends the seal ring's ability to resist mud water and wear resistance.Disadvantage：
4.High requirements for the shape of the sealing groove and sealing ring;
5.Nothing can be done for long-term immersion operation;
6.The starting torque is large, which affects the power of the motor.

E、 RSH - High-contact rubber cover seal-(power supply motor wheel hub structure)

Use Environment：Automobile water pumps, industrial water pumps, electric motorcycles, agricultural machinery, etc.

Advantage：

1.Used for special water vapor erosion needs;
2.The inner sealing lip improves grease retention;
3.Imported reinforced rubber material can better prevent water vapor from entering the bearing;
4.In order to reduce torque and improve sealing performance, The sealing lip with optimized structure is adopted;
5.Because the sealing contact surface adopts high-precision processing, the friction loss of the sealing material is reduced and the seal life is prolonged;
6.The special sealing lip design can automatically compensate for the wear of the seal.

Disadvantage：The friction torque is great.

F、Compound seal

Use Environment：Automobiles, agricultural machinery, etc.

Advantage：

1. The inner sealing lip improves the retention of grease
2.The reinforced rubber material can better prevent the refrigerant from entering the bearing
3.In order to reduce the torque and improve the sealing performance, the optimized structure of the sealing lip
4.The third lip Strengthen the protection of the seal
5.The additional stainless steel ring plays a role of dynamic sealing of water throwing

Disadvantage：The friction torque is large and the cost is high.