creating unbalancing for rotors ??? 1

[vnistra800]

hi friends:

i am techanical instructor and i have got balancing machine in the workshop .

i want clarify to the students phenomena of un balncing and method to treatment it for single and two plane.

what is the differnet ways to create unblance for balance rotors??

what type of mass do u prefer to use temporiry to clarify the idea ???

thanks in advanse for anyone help

best regards

 

[electricpete]

For teaching purposes I would think you would attach a weight (or drill) at any convenient relatively hidden safe place and/or don't draw any attention to it at the beginning of the training.

Approach the balance as if position of unbalance is unknown. Then afterwards if you want you can show them your hidden unbalance weight and see how close your correction weight is to equal/opposite.

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[rob768]

Depending on what equipment you use, and the current balancing quality, you can choose weight and position on the basis of G-classes, applicable for the construction or instrument you use. If for the instrument a quality class of for instance G6.3 is applicable, apply a mass that will get you into 16 or 40. That's enough to show cause and effect, without getting you in the danger zone.

Be sure the weight are properly fixed! Keep the rotatin speed as low as possible!
Remember: if weights come loose at high speed they are dangerous projectiles that can kill.

 

[Tmoose]

A test rotor formed of 2 disks each with a dozen or so equally spaced axially drilled and tapped holes is pretty nice, allowing good angular positioning. I hid a few setscrews in our test rotor to start.

I use clay or wax for trial weights when by myself, but bolts and washers when around civilians. IF the clay flies off I switch to washers and 2 or 3 wraps of strapping tape

 

[svanels]

We used sheets of lead (mandatory attributes for fishing fanatics) to create unbalance in a fan when simulating field balancing.

 

[vnistra800]

hi friends:

please can u clarify to me more mr. svanels

 

[svanels]

We had a small centrifugal blower, the type you will encounter for boilers, air conditioning units etc, with a lot of vanes.
We hooked it up to an electric motor with v-belt, and used our vb3000 analyser to simulate a field balancing job to train our maintenance craft.
We had a small sheet of lead, the one used to put weight on a fishing hook, and cut it in small rectangular pieces of different sizes. The sheets are about 1 or 2 mm thick.
Fold the rectangle in the middle and put it on a vane, use pliers to fasten the lead to the vane. The centrifugal force will keep the trial weight attached to the fan.

We had a class of 15 people who where given an unbalanced fan and had to correct it using the pieces of lead. The whole field class took about 2 hours.

There are some pictures of this at

http://www.alertanalytical.com

Regards