Torsional Value Analysis - Genset

[desmondzzz3]

Hello,

I am providing an alternator (generator end) to a manufacturer who is going to mate this device to a diesel-fired prime mover – resulting in what we know as a genset.
The integrator is asking me for a Torsional Value Data so he can feel comfortable in knowing this alternator component isn’t going to cause problems to the prime-mover (and thus, the warranty)..
I’ve made 1000’s of these alternator ends (single bearing, connected by SAE plates) and have never had a problem with the connection and the resulting operation of the genset. I also have no idea how to provide this individual with the raw numbers he needs to allow him to run his data and give me a thumbs up or a thumbs down..

Can someone send me to a company or a web site that can help me understand what it entails from my end to provide this possible customer the data they need to crunch their numbers?
I have a script in Excel that will allow me to plug in my *numbers* but just don’t know how to extract the raw data from my alternator…

Any help or direction would be greatly appreciated.

 

[rbulsara]

Torsional data should be on standard alternator data sheets. Ask the alternator mfr.

Rafiq Bulsara

http://www.srengineersct.com

 

[desmondzzz3]

Hello Rafiq,

Thank you for the reply...

Fortunately or unfortunately, I am the manufacturer.. We've done the castings, windings, everything ourselves.. Using, I would say "Tribal Knowledge".. Making an alternator isn't rocket science (for us).. Everybody involved has done this type of work before but none of us are Engineers and I've never had anyone ask for this data before..
Can I take an alternator-end to an engineering firm and they can somehow extrapolate the data I need..?

Thanks again!

 

[rbulsara]

This would fall somewhere between tribal knowledge and the rocket science. I am sure there are formulas involved and even testing/measurement. I am not the expert in that. Ask or wait for some structural folks or manufacturing engineers.

Just curious, if this is in the USA, how does it pass UL/FM listing for a fire pump assembly?

Rafiq Bulsara

http://www.srengineersct.com

 

[israelkk]

Do you have any data about the alternator you manufacture? Such as electrical constant (Ke)? Current? etc.

If the answer is no then you need to do a test. Connect the alternator to a known electric motor and run the motor until your alternator is in the correct speed and current. Then read the current in the motor and multiply it by the motor torque constant Kt. This is the torque your alternator will draw in its working condition.

 

[desmondzzz3]

Thank you both - very much!

Rafiq, I don't have to deal with such Bodies as FM or UL as I'm not in the Life Safety business, per se.. This is an already Listed product by CSA for UL 1004 and CSA 100.22-1

I just need someone to tell me how to extract my housing "strength" (??) to help tell me if the prime mover is going to have issues..

In all candor, I have a Test Engineer (for my potential customer) who has done business with the status quo for a long time. Now comes along an equal but less expensive vendor (me) and all of the sudden there are hurdles.. I know you can't solve personality problems but if you can point me in the right direct for someone to explain TVA...
A better widget never had it so tough..

Thanks!

 

[Hoxton]

Usually the diesel engine maniufacturer has a program to analyse the shaft system (engine + coupling (if any) and driven equipment (ac generator in this case).

The engine maker wants to see a dimensioned generator shaft drawing (side view) with the major compenents and their monments of intertia (J) in kgm2.

I have one in front of me, but i cannot send it for copyright reasons.

I also have a TVC print out, but again cannot send it, sorry.

I suggest you ask the engine maker for an example of what he wants......

If you want more help, I will sketch one out and post it. Sorry i am on holiday at the moment.

 

[desmondzzz3]

Thank you Hoxton!

I have an excel spreadsheet that was given to me where I can plug in values and auto-arrive at an answer - it's just me getting the raw data that's driving me a bit batty..
Anything you can help w/ would be most appreciated..

Hope you have a nice vacation!

Desmond