Shaft in vertical orientation 1

[grunt58]

What are some common ways to retain a shaft in a vertical orientation? The particular application I'm looking at is a 40" dia heat treat furnace circulating fan rated at 1200rmp with a 2" dia shaft. Shaft collar, e-clips what other options are there?

 

[IHQ22]

Would a simple bearing or angular bearing work for your application?

 

[MintJulep]

Tapered roller bearing pressed against a step in the shaft.

 

[JohnRBaker]

If you're modifying an existing fan-shaft, which already had normal radial bearings, originally intended for a horizontal arrangement, you could add a collar and a thrust bearing:

John R. Baker, P.E. (ret)
EX-Product 'Evangelist'
Irvine, CA
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[MJCronin]

There are a particular group of electric motors made just for vertical pumps.

The motors support the weight and thrust of the pump and the motor via a thrust bearing on the top.

Locating the bearing on the top of the motor/pump stack facilitates maintenance and increases bearing life by keeping it away from the hot liquid.

What temperature are you operating at ???

MJCronin
Sr. Process Engineer

 

[Strong]

The heat treat fans that I have worked on (vibration diagnostics and rotor balancing) had a horizontal shaft and fan wheel was mounted on motor shaft. If your vertical shaft fan is also directly mounted to motor, then motor ball bearings may take the rotor weight and thrust without an additional thrust bearing. Mounting resonance may be a concern, especially if 2-pole motor with direct drive is used.

Walt

 

[grunt58]

Strong you are correct; it is direct drive. The motor is mounted directly to the fan shaft with a coupling. The goal is the shaft drops down into the furnace for maintenance so a thrust bearing and shoulder wouldn't work. We have split shaft collars but those can slip down the shaft. I'm thinking pin the shaft collars or a detent in the shaft. The design works well; our customer did R&D and tested it offline continuously for 3 months. There just is no safety factor to keep the fan and shaft from dropping into the furnace.

 

[Strong]

A keyless hub design could work well:

http://couplingcorp.com/products/rigid-coupling/vertical-rigid-couplings/

If the fan shaft gets loose and drops during operation, then it should hit fan case (or added J-shaped clips at wheel periphery. A vibration sensor would then trigger motor shut down before damage to fan wheel or to products inside furnace.

Walt