Good bearing? That depends entirely on the application. If you are making pallet jack wheels, and Chinese bearing is good, but I would not use the same bearing in an electric motor application. Somwhere you mst draw the line between price and quality. Too many manufactureres settle for whatever will last through their warranty.

Russell Giuliano
 

I would characterize our needs to be similar to industrial motors.  We are designing for the 50k-150k hour bearing life range for industrial application.  5-20 years of intermittent to continuous service.

 

The only way to qualify them is to do your own tests on a decent sample of their bearings.

You can do this by buying enough samples and load testing them and cutting them up afterwards to check the material quality etc.

Or

You can buy them and fit them in your motors and wait to see how many warranty claims your get ;)

I'm not trying to joke about the second option (well maybe a little).  I worked for a company that did exactly that but with pumps not motors.  After the warranty claims grew to be equal to several decades worth of the costs savings from those cheaper bearings, the company got religion and went back to the known brands.

Sorry I don't know of any shortcuts to qualifying them properly.

I've sold bearings to many electric motor shops. Price is always the major consideration. They also don't like come-backs or returns. Although Chinese bearings are cheaper, most motor shops elect to stay with Japanese major brands for their proven reliability. They prefer Japenese brads over major brands such as SKF and FAG. For reliability, stay with Nachi, Koyo, NTN, NSK, IKS. They ususally provide the best value and least headaches. The Chinese have quality control problems. If you insist on Chinese bearings, you should elect to go with a high level importer that has extra rounds of quality control, and direct influence in the manufacturing plant in China, such as Peer Bearing, which is owned by SKF. Many importers continue to buy from the cheapest sources in China, and there may be quaility problems from one batch to the next.

Russell Giuliano
 

I work for an importer and distributor that offers anything from "Tier 1" brands down to the very cheapest you can get. We like to think we give the customer the value or lifetime that his engineers require on the bearings, and at a price that satisfies the accountants. The comment above sums it up nicely - if your making wheelbarrows you probably don't need to buy SKF or FAG bearings.

I'm lucky enough to be able to travel to the Far East and see the factories for myself and it's my decision if we go into business with them or not.

There are some dreadful "no name brands" out there - some with very slick websites that in no way reflect the actual factory environment in reality. But, conversely there are some excellent facilities churning out good quality product - sometimes with Japanese or Western backing.

With my own eyes I have seen bearings that are made in China, but boxed as made "elsewhere" for the OEM market.

To the specific question about motors - we sell Chinese bearings to a number of electric motor manufacturers and we have no more warranty issues than with other manufacturers. And they can usually be put down to the usual causes - not necessarily "bearing quality". But we do have to continuously monitor quality by batch sampling.

In summary - find an importer of Chinese bearings that can show you some quality certification, can show you some references and if possible visit the plants yourselves before you take the leap. And then trial/monitor them in a small controlled batch to satisfy your own demands.

China might not be fully "there" yet - but they are learning fast.

I am from the city Wafangdian which is called the beairng capital of China. ZWZ is in our city, there are nearly 700 small or big bearing factories in our city, maybe that is incredible for you, but it is true. I work as a sales engineer nearly 3 years for a company here, according to my experience, the main drawback of chinese bearing is innovation, our company never pay attention to the technical development, just follow the SKF or FAG , if the customer send to the drawing to us , we can produce it ,but never know how to study the advanced product. As to the quality , i think it is very hard to solve the problem , from the raw material, take GCr15(100Cr6,SUJ2,52100) for example, the quality of steel cannot be equal with the developed country , how to gurantee the beairg life can compare with SKF and FAG , that is impossible , what's more , the machine , we use the old grinding machine , heat treatment equipment, that is very difficult to produce the high precision bearing. also the management , i got one complaint from customer , since the scratch on the raceway of bearing , it is caused when the labor assemle the roller through the slot, this can be avioded if the worker is careful. anyway , the china bearing still has a long way to go. The advantage of ours now is just the price,SKF and FAG is 7-10 times expensive than us , if the end customer can accept the shorter bearing life , that is ok.  

Wafangdian China ,Joe   

Thanks everyone for your input.  Our bearing requirements are between the wheelbarrow and helicopter drive.

I think for us the "value" bearings will not do because 1) we must rate our drives in terms of L10 life and 2) our drives will be rebuilt at some point in the lifespan and the customer will see the brand of bearing being used.

Don't knock yourself too hard Joe. I know Wafangdian quite well. There are 100's of bearing companies there! Sounds like yours is one of the older ones, but the same was said of Japanese beairngs not so long ago. Things will get better if people like you strive for improvement.

Quote:

2) our drives will be rebuilt at some point in the lifespan and the customer will see the brand of bearing being used.

Lol.  I guess appearances count.

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Hippo 41, thanks for your word , acctually my factory is not a very old one ,established at 1989. You have come to Wafangdian for several times i think , next time come here , i will invite you have a drink :). It needs a long to catch up with Japanese , i am optimistic about our future.