Something Different

[Mark Bullard]

Here is a balance job I did the other day. It is the heaviest part we have every done. Weight on this unit was almost 13,000lbs. It looks like a planer rotor without the blades. But I think it is used to chop up polymers. The overall length was 110" , the rotor was 60" x 30". Shaft and all was made out of a solid piece of steel. Running speed was 440 rpm and I am sure that it has a lot of horsepower to drive it. We balance it to a G2.5 spec. Balancing speed was 150 rpm.

 

[Norm Doerr]

Very cool.. Looks like a Sunnen Hone mandrel.... a BIG Sunnen Hone Mandrel..

 

[Mike Culhane]

Wow! The bearings on the end rollers must have been sweating!

 

[Mark Bullard]

Bearings on this machine are pretty good. They are special hardened wheels with rollers bearing inside. So they will take a lot of weight. Our machine is rated for 12,000 lbs. with a short duty cycle of 15,000 lbs. The scary part is to turn this heavy rotor 150 rpm in the open. Makes you want to back up a little.

 

[tnrcboatracer]

That looks like a rotor for a plastic shredder/granulator. It is used to chop plastic flash/scrap into tiny little pieces. The knives look like thick planer blades.

 

[Danny King]

That's a chunk of steel right there.

 

[Steve P]

Yep, we have several of them here at work they can turn a 4' x 8' sheet of 0.250" Lexan into quarter inch pieces in minutes. We have one that they put hunks of plastic 2" thick into it and it eats them up.

 

[RaceMechaniX]

Hey Mark,

Is that a Hoffman balancer? For the electric motor rotors I also balance to G2.5, but the rotors are only 25mm in diameter and 400g.

Does having the drive belt go around a non-circular surface cause issues??

Tyler

 

[Mark Bullard]

Yes you are right. It is a Hoffman hard bearing balance machine. I have a smaller Hoffman also that will go to 200 lbs. I am in the electric motor business also. Have not had a problem with the non-circular surface. And on the motors we repair our spec is a G 1. Not to many machines can go this low with ease. We did eight feed water pump impellers to a G 0.4 the other day and trim the assembly to a G 0.4 after it was put together on its common shaft.

 

[Mike Hughes]

The scary part is to turn this heavy rotor 150 rpm in the open. Makes you want to back up a little.

The first thing I thought when I saw the pic.

 

[Tom Foley]

The scary part is to turn this heavy rotor 150 rpm in the open. Makes you want to back up a little.

The first thing I thought when I saw the pic.

Yeah !