Why we use electrically insulated bearing?
The electrically insulated bearings adopts a special spraying process. The outer surface of the bearing is spray-plated with a high-quality coating. The coating and the substrate have a strong binding force and good insulation performance. It can avoid the electric corrosion of the bearing by the induced current and prevent the current from affecting the grease and rolling elements. The damage caused by the raceway increases the service life of the bearing. The process is continuously improved. In the electrically insulated bearing, there is a layer with a thickness of 100 μm on the surface of the outer ring or the inner ring, which can withstand a voltage of up to 1000 V DC. The special spraying process can form a coating with uniform thickness and extremely strong adhesion, and then further processing to make it immune to the influence of moisture and humidity.
Electrically Insulated bearings are mainly used in motor products. Its use depends on the power state of the motor. Normal grid power supply has no high-frequency voltage and current components. Generally, electrically insulated bearings are not used. Only high-voltage motors and large motors such as 400 or more are used.
But now the frequency conversion power supply, The power quality contains a lot of high-frequency components, causing the motor shaft current to increase, so should be considered in the specifications above 400, even the smallest specifications also consider the installation to use Electrically Insulated Bearings, such as electric motors, electric rail locomotives, and other main motors generally use about 100KW. Electrically insulated bearings must be used (or other insulation structures must be used to ensure that shaft current does not flow).
Electrically insulated bearings can avoid damage caused by electrical corrosion, so compared with ordinary bearings, they can ensure more reliable operation in motors. Compared with other insulation methods, such as shaft or housing insulation, it is more cost-effective and reliable. The dimensions and basic technical characteristics of insulated bearings are the same as those of non-insulated bearings, so they are 100% interchangeable.
According to the bearing structure, insulated bearings can be divided into electrically insulated deep groove ball bearings, electrically insulated angular contact ball bearings, electrically insulated cylindrical roller bearings, Insulated taper roller bearings, inner or outer ring insulated bearings with oxide coatings, and hybrid bearings with electrically insulated ceramic rolling elements and so on.
Insulated deep groove ball bearings are suitable for high-speed and even very high-speed operation, and are very durable and do not require frequent maintenance. This type of bearing has a small friction coefficient, high limiting speed, and a wide range of sizes and forms. It is used in low-noise motors and other industries. It is the most widely used type of insulated bearing. It mainly bears radial load and can also bear -quantitative axial load.
Insulated angular contact ball bearings can support both radial and axial loads. Can work at higher speeds. The larger the contact angle, the higher the axial load capacity. High-precision and high-speed bearings usually adopt a contact angle of 15 degrees. Under the action of axial force, the contact angle will increase. Inner or outer ring of the insulated bearings with oxide coatings and hybrid bearings with electrically insulated ceramic rolling elements are mainly named for their product characteristics.
Even if the motor is strictly controlled during the manufacturing process, it is difficult to completely avoid the magnetic asymmetry of the armature and the rotor. This asymmetry will generate a voltage between the stators, which will generate a current through the bearing, especially in AC motors, this current generates pits, melting marks, galvanic erosion, discoloration, wear and other damage on the surface of the bearing raceway and rolling elements. Of course, this phenomenon also occurs with motors using inverter and frequency conversion technology. In order to stop this kind of current from flowing through the bearing, it is necessary to cut off the circuit, and the insulated bearing and insulated bearing room have emerged at the historic moment. Insulated bearing chamber is made of a certain hardness of insulating material in the bore and end face of the bearing chamber.
CoatMaster As the Top Brand of China Insulated Bearing manufacturer, focus on reserch & develop Electrically Insulated Bearing, it can provide various types of insulated bearings
- Electrically insulated deep groove ball bearing
- Electrically insulated angular contact ball bearing
- Electrically insulated cylindrical roller bearing
- Electrically insulated tapered roller bearing
- Electrically insulated spherical roller bearing
- Electrically insulated spherical roller thrust bearing
- Electrically insulated linear motion bearing
- Inner or outer ring insulated bearing with oxide coating
- Hybrid bearing with electric insulating ceramic rolling element
CoatMaster as the China bearing manufacturer & exporter & supplier, it can supply complete electrically insulated bearing, Our large quantity insulated deep groove ball bearing Stock can meet your need with good quality and fast delivery, Also you can find FAG Current insulated Bearing, NSK Insulated Bearing, SKF INSOCOAT Bearing, NTN, NKE are also have manufacture production for electrically insulated Bearing, the other type and brand insulated deep groove ball bearing, insocoat tapered roller bearing, Small order is available also by us, DHL,UPS,Fedex is the best choice for shipment for small quantity, the weight more than 80kg and less than 500 kg, we suggest ship them by air to port, we alway supply for the best solution for your applications, just contact with CoatMaster for start our service.
