Linqing Nine Star Bearing Science & Technology Co.,Ltd » News http://www.ninestarbearing.com Electrically Insulated Bearing, insulated bearing, insulated ball bearings Sun, 06 Aug 2017 08:32:24 +0000 zh-CN hourly 1 https://wordpress.org/?v=4.1.41 The causes and effects of VFD-supplied motor shaft and bearing currents http://www.ninestarbearing.com/the-causes-and-effects-of-vfd-supplied-motor-shaft-and-bearing-currents/ http://www.ninestarbearing.com/the-causes-and-effects-of-vfd-supplied-motor-shaft-and-bearing-currents/#comments Sun, 06 Aug 2017 08:32:24 +0000 http://www.ninestarbearing.com/?p=4986 Shaft currents are induced because of the high frequency of the voltage pulses sent to the motor from the VFD. Recall that a pulse-width modulated VFD creates a synthesized sine wave by firing its output transistors many thousands of times per second. These pulses form high-frequency waves sent along the motor cable to the motor. Since impedance is inversely proportional to frequency, the capacitances of the cable and motor present little or no impedance to these high-frequency pulses. As a result, circulating currents can readily flow in the motor shaft. With sufficient magnitude,  and in the absence of corrective measures, these shaft currents can pass through the bearings and races to the motor frame, causing bearing pitting or “fluting” – regular, tightly spaced grooves on the bearing races – via a process referred to as Electric Discharge Machining (EDM). Ultimately, these irregularities will cause bearing failure.

 

Linqing Nine Star Bearing Science & Technology Co., Ltd            

(Insulated bearing, Hybrid ceramic bearing and  Brass cage DGBB)

Follow us via E-mail info@jxkjzc.com; Website www.ninestarbearing.com.

 

]]> http://www.ninestarbearing.com/the-causes-and-effects-of-vfd-supplied-motor-shaft-and-bearing-currents/feed/ 0 FAG Insulated Bearing Description & Range of sizes http://www.ninestarbearing.com/fag-insulated-bearing-description-range-of-sizes/ http://www.ninestarbearing.com/fag-insulated-bearing-description-range-of-sizes/#comments Sun, 30 Jul 2017 07:12:22 +0000 http://www.ninestarbearing.com/?p=4978 Product Description:

To prevent such damage, the FAG offers current-insulated bearings:

  • Current-insulated bearings and hybrid bearings
  • Current-insulated bearings have either an outer ring (J20 A, J20 AA, J20B) or an inner ring (J20C)
  • that is insulated with thin ceramic coating
  • Different coating types are available for optimum functional performance

 

Types of coatings - Range of Sizes:

  • Disruptive voltage 500 VDC 1000 VDC 1000 VDC 1000 VDC
  • Environment dry dry dry/damp dry/damp
  • Coating thickness 200 μm ≈200 μm ≈200 μm
  • Applicable dimensions 70 1400 mm
  • outside diameter 70 1400 mm
  • outside diameter 70 500 mm
  • outside diameter 70 340 mm
  • Inner ring bore

 

Linqing Nine Star Bearing Science & Technology Co., Ltd            

(Insulated bearing, Hybrid ceramic bearing and  Brass cage DGBB)

Follow us via E-mail info@jxkjzc.com; Website www.ninestarbearing.com.

 

]]> http://www.ninestarbearing.com/fag-insulated-bearing-description-range-of-sizes/feed/ 0 7004 ce/hcp4atbta & 7004 cega/hcp4a delivery pictures http://www.ninestarbearing.com/7004-cehcp4atbta-7004-cegahcp4a-delivery-pictures/ http://www.ninestarbearing.com/7004-cehcp4atbta-7004-cegahcp4a-delivery-pictures/#comments Sun, 23 Jul 2017 05:38:20 +0000 http://www.ninestarbearing.com/?p=4960 Here sharing the delivery pictures of NINE STAR Hybrid ceramic bearings
7004 ce/hcp4atbta, and  7004 cega/hcp4a .


Linqing Nine Star Bearing Science & Technology Co., Ltd            

(Insulated bearing, Hybrid ceramic bearing and  Brass cage DGBB)

Follow us via E-mail info@jxkjzc.com; Website www.ninestarbearing.com.

 

]]> http://www.ninestarbearing.com/7004-cehcp4atbta-7004-cegahcp4a-delivery-pictures/feed/ 0 6316-M-J20AA-C3 insulated bearing FAG http://www.ninestarbearing.com/6316-m-j20aa-c3-insulated-bearing-fag/ http://www.ninestarbearing.com/6316-m-j20aa-c3-insulated-bearing-fag/#comments Sat, 15 Jul 2017 10:04:30 +0000 http://www.ninestarbearing.com/?p=4952 NINE STAR  6316-M-J20AA-C3  Insulated bearings:

Bearing code number 6316-M-J20AA-C3
Bearing type Deep groove ball bearing
Insulated type Inner ring or outer ring
Demensions 80x170x39mm
d 80mm
D 170mm
B 39mm
Service Neutral/OEM/As your request
Package Carton boxes /Wooden Cases /Pallets
Stock qty 18pcs

Dear Purchasing manager, it is my great pleasure to inform you that we still have 18pcs of

6316-M-J20AA-C3  bearing in stock at the moment. Please feel free to contact us through EMAIL

or SKYPE if you have request for  6316-M-J20AA-C3  bearings and we will spare no efforts to

satisfy your requirements by rendering you the superior quality, the most competitive prices,

premium service and any other specific need.

Similar Insulated bearings:

6010-M-J20AA-C3            6011-M-J20AA-C3             6012-M-J20AA-C3

6014-M-J20AA-C3            6016-M-J20AA-C3             6018-M-J20AA-C3

6019-M-J20AA-C3            6020-M-J20AA-C3             6021-M-J20AA-C3

6022-M-J20AA-C3            6024-M-J20AA-C3             6026-M-J20AA-C3

6028-M-J20AA-C3            6030-M-J20AA-C3             6032-M-J20AA-C3

6032-M-J20AA-C3            6036-M-J20AA-C3             6038-M-J20AA-C3

6040-M-J20AA-C3            6044-M-J20AA-C3             6048-M-J20AA-C3

6052-M-J20AA-C3            6056-M-J20AA-C3

 

6210-M-J20AA-C3            6211-M-J20AA-C3            6212-M-J20AA-C3

6213-M-J20AA-C3            6214-M-J20AA-C3            6215-M-J20AA-C3

6216-M-J20AA-C3            6217-M-J20AA-C3            6218-M-J20AA-C3

6219-M-J20AA-C3            6220-M-J20AA-C3            6221-M-J20AA-C3

6222-M-J20AA-C3            6224-M-J20AA-C3            6226-M-J20AA-C3

6228-M-J20AA-C3            6230-M-J20AA-C3            6232-M-J20AA-C3

6232-M-J20AA-C3            6236-M-J20AA-C3            6238-M-J20AA-C3

6240-M-J20AA-C3            6244-M-J20AA-C3

 

6310-M-J20AA-C3            6311-M-J20AA-C3             6312-M-J20AA-C3

6313-M-J20AA-C3            6314-M-J20AA-C3             6315-M-J20AA-C3

6316-M-J20AA-C3            6317-M-J20AA-C3             6318-M-J20AA-C3

6319-M-J20AA-C3            6320-M-J20AA-C3             6321-M-J20AA-C3

6322-M-J20AA-C3            6324-M-J20AA-C3             6326-M-J20AA-C3

6328-M-J20AA-C3            6330-M-J20AA-C3             6332-M-J20AA-C3

6332-M-J20AA-C3            6336-M-J20AA-C3             6338-M-J20AA-C3

6340-M-J20AA-C3            6344-M-J20AA-C3

 

6410-M-J20AA-C3            6411-M-J20AA-C3             6412-M-J20AA-C3

6413-M-J20AA-C3            6414-M-J20AA-C3             6415-M-J20AA-C3

6416-M-J20AA-C3            6417-M-J20AA-C3             6418-M-J20AA-C3

6419-M-J20AA-C3            6420-M-J20AA-C3

 

Linqing Nine Star Bearing Science & Technology Co., Ltd 

( Insulated bearing, Hybrid ceramic bearing and  Brass cage DGBB)

Follow us via E-mail info@jxkjzc.com; Website www.ninestarbearing.com.

 

 

]]> http://www.ninestarbearing.com/6316-m-j20aa-c3-insulated-bearing-fag/feed/ 0 NINE STAR NU322ECM/C3 VL0241 Insulated bearings http://www.ninestarbearing.com/nine-star-nu322ecmc3-vl0241-insulated-bearings/ http://www.ninestarbearing.com/nine-star-nu322ecmc3-vl0241-insulated-bearings/#comments Sun, 09 Jul 2017 02:23:47 +0000 http://www.ninestarbearing.com/?p=4950 NINE STAR  NU322ECM/C3 VL0241 Insulated bearings:

Bearing code number NU322ECM/C3 VL0241
Bearing type Cylindrical roller  bearing
Insulated type Inner ring or outer ring
Demensions 110*240*50mm
d 110mm
D 240mm
B 50mm
Service Neutral/OEM/As your request
Package Carton boxes /Wooden Cases /Pallets

Dear Purchasing manager, it is my great pleasure to inform you that we still have 18pcs of

NU322ECM/C3VL0241  bearing in stock at the moment. Please feel free to contact us through EMAIL

or SKYPE if you have request for NU322ECM/C3VL0241 bearings and we will spare no efforts to

satisfy your requirements by rendering you the superior quality, the most competitive prices,

premium service and any other specific need.

Similar insulated bearings:

NU1012ECM/C3VL0241     NU1014ECM/C3VL0241     NU1016ECM/C3VL0241

NU1018ECM/C3VL0241     NU1019ECM/C3VL0241     NU1020ECM/C3VL0241

NU1021ECM/C3VL0241     NU1022ECM/C3VL0241     NU1024ECM/C3VL0241

NU1026ECM/C3VL0241     NU1028ECM/C3VL0241      NU1030ECM/C3VL0241

NU1032ECM/C3VL0241     NU1032ECM/C3VL0241      NU1036ECM/C3VL0241

NU1038ECM/C3VL0241     NU1040ECM/C3VL0241     NU1044ECM/C3VL0241

 

NU210ECM/C3VL0241       NU211ECM/C3VL0241       NU212ECM/C3VL0241

NU213ECM/C3VL0241       NU214ECM/C3VL0241       NU215ECM/C3VL0241

NU216ECM/C3VL0241       NU217ECM/C3VL0241       NU218ECM/C3VL0241

NU219ECM/C3VL0241       NU220ECM/C3VL0241       NU221ECM/C3VL0241

NU222ECM/C3VL0241       NU224ECM/C3VL0241       NU226ECM/C3VL0241

NU228ECM/C3VL0241       NU230ECM/C3VL0241       NU232ECM/C3VL0241

NU232ECM/C3VL0241       NU236ECM/C3VL0241       NU238ECM/C3VL0241

NU240ECM/C3VL0241       NU244ECM/C3VL0241

 

NU310ECM/C3VL0241      NU311ECM/C3VL0241      NU312ECM/C3VL0241

NU313ECM/C3VL0241      NU314ECM/C3VL0241      NU315ECM/C3VL0241

NU316ECM/C3VL0241      NU317ECM/C3VL0241      NU318ECM/C3VL0241

NU319ECM/C3VL0241      NU320ECM/C3VL0241      NU321ECM/C3VL0241

NU322ECM/C3VL0241      NU324ECM/C3VL0241      NU326ECM/C3VL0241

NU328ECM/C3VL0241      NU330ECM/C3VL0241      NU332ECM/C3VL0241

NU332ECM/C3VL0241      NU336ECM/C3VL0241      NU338ECM/C3VL0241

NU340ECM/C3VL0241      NU344ECM/C3VL0241

 

NU410ECM/C3VL0241      NU411ECM/C3VL0241       NU412ECM/C3VL0241

NU413ECM/C3VL0241      NU414ECM/C3VL0241       NU415ECM/C3VL0241

NU416ECM/C3VL0241      NU417ECM/C3VL0241       NU418ECM/C3VL0241

NU419ECM/C3VL0241      NU420ECM/C3VL0241

 

Linqing Nine Star Bearing Science & Technology Co., Ltd 

( Insulated bearing, Hybrid ceramic bearing and  Brass cage DGBB)

Follow us via E-mail info@jxkjzc.com; Website www.ninestarbearing.com.

 

 

]]> http://www.ninestarbearing.com/nine-star-nu322ecmc3-vl0241-insulated-bearings/feed/ 0 NINE STAR NU224ECM/C3 VL0241 Insulated bearings http://www.ninestarbearing.com/nine-star-nu224ecmc3-vl0241-insulated-bearings/ http://www.ninestarbearing.com/nine-star-nu224ecmc3-vl0241-insulated-bearings/#comments Sun, 02 Jul 2017 10:25:45 +0000 http://www.ninestarbearing.com/?p=4946 NINE STAR  NU224ECM/C3 VL0241 Insulated bearings:

Bearing code number NU224ECM/C3 VL0241
Bearing type Cylindrical roller  bearing
Insulated type Inner ring or outer ring
Demensions 120*215*40mm
d 120mm
D 215mm
B 40mm
Service Neutral/OEM/As your request
Package Carton boxes /Wooden Cases /Pallets

Dear Purchasing manager, it is my great pleasure to inform you that we still have 18pcs of

NU224ECM/C3VL0241  bearing in stock at the moment. Please feel free to contact us through EMAIL

or SKYPE if you have request for NU224ECM/C3VL0241 bearings and we will spare no efforts to

satisfy your requirements by rendering you the superior quality, the most competitive prices,

premium service and any other specific need.

Similar insulated bearings:

NU1012ECM/C3VL0241     NU1014ECM/C3VL0241     NU1016ECM/C3VL0241

NU1018ECM/C3VL0241     NU1019ECM/C3VL0241     NU1020ECM/C3VL0241

NU1021ECM/C3VL0241     NU1022ECM/C3VL0241     NU1024ECM/C3VL0241

NU1026ECM/C3VL0241     NU1028ECM/C3VL0241      NU1030ECM/C3VL0241

NU1032ECM/C3VL0241     NU1032ECM/C3VL0241      NU1036ECM/C3VL0241

NU1038ECM/C3VL0241     NU1040ECM/C3VL0241     NU1044ECM/C3VL0241

 

NU210ECM/C3VL0241       NU211ECM/C3VL0241       NU212ECM/C3VL0241

NU213ECM/C3VL0241       NU214ECM/C3VL0241       NU215ECM/C3VL0241

NU216ECM/C3VL0241       NU217ECM/C3VL0241       NU218ECM/C3VL0241

NU219ECM/C3VL0241       NU220ECM/C3VL0241       NU221ECM/C3VL0241

NU222ECM/C3VL0241       NU224ECM/C3VL0241       NU226ECM/C3VL0241

NU228ECM/C3VL0241       NU230ECM/C3VL0241       NU232ECM/C3VL0241

NU232ECM/C3VL0241       NU236ECM/C3VL0241       NU238ECM/C3VL0241

NU240ECM/C3VL0241       NU244ECM/C3VL0241

 

NU310ECM/C3VL0241      NU311ECM/C3VL0241      NU312ECM/C3VL0241

NU313ECM/C3VL0241      NU314ECM/C3VL0241      NU315ECM/C3VL0241

NU316ECM/C3VL0241      NU317ECM/C3VL0241      NU318ECM/C3VL0241

NU319ECM/C3VL0241      NU320ECM/C3VL0241      NU321ECM/C3VL0241

NU322ECM/C3VL0241      NU324ECM/C3VL0241      NU326ECM/C3VL0241

NU328ECM/C3VL0241      NU330ECM/C3VL0241      NU332ECM/C3VL0241

NU332ECM/C3VL0241      NU336ECM/C3VL0241      NU338ECM/C3VL0241

NU340ECM/C3VL0241      NU344ECM/C3VL0241

 

NU410ECM/C3VL0241      NU411ECM/C3VL0241       NU412ECM/C3VL0241

NU413ECM/C3VL0241      NU414ECM/C3VL0241       NU415ECM/C3VL0241

NU416ECM/C3VL0241      NU417ECM/C3VL0241       NU418ECM/C3VL0241

NU419ECM/C3VL0241      NU420ECM/C3VL0241

 

Linqing Nine Star Bearing Science & Technology Co., Ltd 

( Insulated bearing, Hybrid ceramic bearing and  Brass cage DGBB)

Follow us via E-mail info@jxkjzc.com; Website www.ninestarbearing.com.

 

 

]]> http://www.ninestarbearing.com/nine-star-nu224ecmc3-vl0241-insulated-bearings/feed/ 0 Best Practices for Mitigating Bearing Damage http://www.ninestarbearing.com/best-practices-for-mitigating-bearing-damage/ http://www.ninestarbearing.com/best-practices-for-mitigating-bearing-damage/#comments Sun, 25 Jun 2017 01:19:21 +0000 http://www.ninestarbearing.com/?p=4943 Manufacturers and users of inverter-ready motors should strive to protect the motors’ bearings as well as their windings. The following measures have proven effective under actual operating conditions and should be considered for inclusion in any NINE STAR standards updates:

For motors above 100 hp, in which both circulating currents and common-mode voltages can cause bearing damage, an insulated bearing on one end and a shaft-grounding ring on the other provides the best protection from electrical bearing damage.

For motors 100 hp and less, adding a shaft-grounding ring either inside of a motor or externally effectively protects bearings and attached equipment from currents.

 

Linqing Nine Star Bearing Science & Technology Co., Ltd 

( Insulated bearing, Hybrid ceramic bearing and  Brass cage DGBB)

Follow us via E-mail info@jxkjzc.com; Website www.ninestarbearing.com.

 

 

]]> http://www.ninestarbearing.com/best-practices-for-mitigating-bearing-damage/feed/ 0 The Need for Updated Standards in Bearings http://www.ninestarbearing.com/the-need-for-updated-standards-in-bearings/ http://www.ninestarbearing.com/the-need-for-updated-standards-in-bearings/#comments Sun, 18 Jun 2017 10:03:00 +0000 http://www.ninestarbearing.com/?p=4939 NINE STAR is in the unique position to update its bearings' standard, Motors and Generators, to more clearly state that common-mode shaft voltages are present in virtually all motors fed by pulse-width-modulated VFDs.

NINE STAR’s current standards say motors controlled by VFDs containing insulated-gate bipolar transistors should be designed to withstand repeated spikes of up to 3.1 times the motor’s rated voltage at rise times not less than 0.1 microsecond. Yet, when addressing the potential for bearing currents, the language is far less prescriptive.

Shaft voltages can result in the flow of destructive currents through motor bearings, manifesting themselves through pitting of the bearings, scoring of the shaft, and eventual bearing failure. It recommends bearing insulation at one end of larger motors (defined as “usually 500 frame or larger,” horsepower unspecified), if the peak shaft voltage is greater than 300 millivolts. Unfortunately, the paragraph dealing with these larger motors only mentions circulating end-to-end shaft currents caused by magnetic dissymmetries under sinusoidal operation. It fails to add that the bearings of large motors also can be plagued by VFD-induced high-frequency, capacitively coupled common-mode voltages.

 

Linqing Nine Star Bearing Science & Technology Co., Ltd 

( Insulated bearing, Hybrid ceramic bearing and  Brass cage DGBB)

Follow us via E-mail info@jxkjzc.com; Website www.ninestarbearing.com.

 

]]> http://www.ninestarbearing.com/the-need-for-updated-standards-in-bearings/feed/ 0 Hybrid bearings–Protect equipment from stray electric currents http://www.ninestarbearing.com/hybrid-bearings-protect-equipment-from-stray-electric-currents/ http://www.ninestarbearing.com/hybrid-bearings-protect-equipment-from-stray-electric-currents/#comments Sun, 11 Jun 2017 01:30:02 +0000 http://www.ninestarbearing.com/?p=4937

Protect equipment from stray electric currents

To support the trend towards electrically motorized wheel drives, bearings have to perform under high temperatures, shocks and vibrations and stray electric currents. NINE STAR hybrid bearings can handle it.

Featuring the benefits of ceramic rollers

NINE STAR hybrid bearings offer OEMs several benefits associated with ceramic rolling elements. Their electrical insulation properties virtually eliminate risk of electrical erosion in the rolling contacts, even under poor lubrication. Low friction and centrifugal forces facilitate high-speed capabilities. End-users ultimately enjoy longer service life and reduced lifecycle costs.

 

Linqing Nine Star Bearing Science & Technology Co., Ltd 

( Insulated bearing, Hybrid ceramic bearing and  Brass cage DGBB)

Follow us via E-mail info@jxkjzc.com; Website www.ninestarbearing.com.

 

]]> http://www.ninestarbearing.com/hybrid-bearings-protect-equipment-from-stray-electric-currents/feed/ 0 Influence of insulated bearings in machines of inverter-based drive systems http://www.ninestarbearing.com/influence-of-insulated-bearings-in-machines-of-inverter-based-drive-systems/ http://www.ninestarbearing.com/influence-of-insulated-bearings-in-machines-of-inverter-based-drive-systems/#comments Sun, 04 Jun 2017 09:43:46 +0000 http://www.ninestarbearing.com/?p=4908 The high-frequency (HF) circulating bearing current that may occur in the machines of the inverter-based drive systems can be reduced or even completely suppressed by the use of the electrically insulated bearings or the insulated inner bearing seats. This paper proposes a method to calculate the influence of the thickness of the insulating coat on the obtained current reduction as a function of the several machine-design parameters. The parameters of the equivalent circuit are derived from an eddy-current model. The calculation considers the transient nature of the current flow. For the standard fan-cooled motors with up to 500-KW rated power, a minimum thickness of the insulating coat of 250 mum is required to reduce the circulating bearing currents to values where the apparent bearing-current density is less than 0.1 A/mm2, which is commonly taken as the threshold to the bearing failure.

 

Linqing Nine Star Bearing Science & Technology Co., Ltd 

( Insulated bearing, Hybrid ceramic bearing and  Brass cage DGBB)

Follow us via E-mail info@jxkjzc.com; Website www.ninestarbearing.com.

 

]]> http://www.ninestarbearing.com/influence-of-insulated-bearings-in-machines-of-inverter-based-drive-systems/feed/ 0