You can find the design information from any machinery design textbook: although I am not to sure about 'select' & 'standard' terminology.

I used to do it using reference to a "Theory of Machines" textbook which probably went out of print in the mid 1970's; not because the theory was wrong; I must add. Depending on your locale you can probably find a Machinerys Handbook lurking about. ■

Flywheels are used to store energy aren't they?

First work out how much energy needs to be stored then design the flywheel, be it small and fast, or big and slow.

Like louispanjang I too used textbooks, two come to mind

Mechanics of Machines, Barnacle & Walker

Mechanics of Machines, Morrison & Crossland

(both 1964, I'm showing my age)

Of course now there's Google, but beware of Wikipedia! ■

Dear goodisme,

The first step is a torsinal vibration analysis.

This analysis will give you the required moment of inertia of the required flywheel on a specific position in the system.

This is in combination with the stiffness of the shafts and flexible couplings in the drive line and the moments of inertia of the coupled equipment.

Whether that can be a standard (SAE) flywheel is doubtful.

success

Teus ■

Originally Posted by Teus Tuinenburg

Dear goodisme,

The first step is a torsinal vibration analysis.

This analysis will give you the required moment of inertia of the required flywheel on a specific position in the system.

This is in combination with the stiffness of the shafts and flexible couplings in the drive line and the moments of inertia of the coupled equipment.

Whether that can be a standard (SAE) flywheel is doubtful.

success

Teus

A torsional stiffness analysis used to involve the construction of a Holtzer Table. Used as a keyword that might help your search. See also DIN 6892 & www.rwcouplings.com ■

Dear louispanjang,

A torsional vibration analysis is nowadays performed by a sophisticated computer program, capabable of considering many masses and springs and frequency orders.

Even vibration stresses and dampening energies are calculated.

In case a flywheel has to store energy (like in a cobustion engine), the required 1/2*Im*omega^2 has to be determined. Then the torsional vibration analysis has to be executed.

BR

Teus ■

Dear Tues,

Why flywheel is used in a system?If this is an advantages or disadvantage for a system?

I think as the flywheel is more heavier,this is not good for machine and motor as we might need stronger motor.However,it is said that flywheel helps motor.This is why I can not understand why flywheel is indeed used?

What would happen for a system if we remove flywheel?

All the Best

Hamidreza ■

Flywheels have 4 basic purposes:

1. Increase coasting time to control material volume in chute during a shutdown without power - eliminating plugging or spillage

2. Eliminating undesirable belt sag and take-up motion,

3. Control shock wave impulses at all pulley terminal points during starting, aborted starts, and stopping without power.

4. Holdback load sharing on large inclined conveyors - depends on belt geometry, et. al. You need to understand dynamic analysis methods to apply the flywheel effectively and safely.

Only use when absolutely necessary. Only use when you understand the principles. The noted vibration between flywheel and drive components is a secondary item to be controlled. More important with flywheels on two or more drives. ■

Thank you for your advice.

I seem unable to understand why flywheel prevent belt sag.

As per your comments we can use flywheel for all belt coupling in order to prevent belt sag.

Also,you advised the flywheel is good for stop and start.However,I think flywheel is not good for start as it need more power and the motor may suffer.Why flywheel is good for start?

Why we need power to stop?For stopping machine I think we need no power.

As per your comments it seems flywheel is good all the time for all application.

Please kindly explain more enable me to understand better.

Best Regards

Hamidreza ■

Hamidreza

There are obvious answers to your questions that have been published over and over. Please do some reading, rather than the informed repeatedly must answer the same again and again.

The belt is an elastic body, which stretchs and contracts with changing elastic/tensile/compression waves that are the domain of elastic transient dynamics that some call dynamic analysis. You cannot analyze a long flexible body as a rigid body.

Think of a conveyor with a downhill slope and then an uphill slope. During stopping, the uphill section will be retarded by gravity, while the downhill will be accelerated by gravity. With sufficient slopes a large sag may occur at their apex, and the take-up will lose travel into the apex with likely large sag.

REad more. ■

Dear Expert,

Thank you very much for your valuable advice.

Please kindly reply to my other questions as bellow,

Also,you advised the flywheel is good for stop and start.However,I think flywheel is not good for start as it need more power and the motor may suffer.Why flywheel is good for start?

Why we need power to stop?For stopping machine I think we need no power.

As per your comments it seems flywheel is good all the time for all application.

Please kindly explain more enable me to understand better.

Best Regards

Hamidreza ■

Originally Posted by goodisme

how do we compute to select a standard fly wheel

Before embarking on a discrete application it would be helpful if the thread starter gave more indication of his intent. I, for one, suspect that there are many more flywheels on crushers and such as there are on conveyors.

This thread is over 4 years past and we'll probably never know if the flywheel is still on the shaft, wherever. ■

Hello,

The flywheel increases the moment of inertia (mk square value) of the conveyor. The conveyor including its drive components' resistance being remaining same, the flywheel will increase the conveyor coasting time. Choose the flywheel mk square value such that resulting coasting time becomes acceptable.

As stated above, the flywheel increases the moment of inertia of the conveyor (including drive) i.e. conveyor will take longer time to reach to operating speed, if drive torque being same. So one has to analyse the implication both ways i.e. during starting as well as stoppage.

Regards,

Ishwar G. Mulani

Author of Book : Engineering Science And Application Design For Belt Conveyors (new print November, 2012)

Author of Book : Belt Feeder Design And Hopper Bin Silo

Advisor / Consultant for Bulk Material Handling System & Issues.

Pune, India.

Tel.: 0091 (0)20 25871916

Email: conveyor.ishwar.mulani@gmail.com

Website: www.conveyor.ishwarmulani.com ■