Dear All,

Anyone know what BS or ISO standard suitable for high speed balancing of rigid rotor (Turbine)? Much tanks to your help.

Thanks- Joe & William,

The steam turbine is rigid rotor and we planned to do a high speed balancing after some modification. However, I am not sure whether ISO1940 is applicable for high speed balancing.

This message has been edited. Last edited by: sy04050,

Sy#,
We have a couple of expander rotors which run at just over 23,000rpm. They run below their first critical and are balanced to G2.5 which gives pretty smooth performance.
Joe Mc Cormack

Rigid rotors can be balanced in any 2 planes. - This is a theorem.

As mentioned turbo-expanders are sucessfully low speed balanced (Read rigid rotor balanced.), and some operate faster than the mentioned 23,000 rpm. Why? Because they are rigid.

Are you sure your turbine ins a rigid rotor? (Note: The balancing standards are changing some terms regarding 'rigid rotor.')

In the last week there was a vote on ISO/FDIS 19499, Mechanical vibration — Balancing —Guidance on the use and application of balancing standards (French title Vibration mécaniques — Équilibrage — Lignes directrices pour l'utilisation et l'application de normes d'équilibrage. This is a guide to balancing standards. The US voted to approve it; if approved by the ISO countries this will soon be a standard.

19499 provides a guide to what standards would be required for various situations to help people with this type of question.

International voting finishes on 23 June 2007.

Here is the news:

http://www.iso.org/iso/en/CatalogueDetailPage.Catalogue...=42442&scopelist=ALL

Perhaps you want to refer to API RP for Repair of Rotors.

Doesn't the OEM specify the balancing standard in their manual?

To me, the phrase "high speed balancing" implies that you are in a shop and you intentionally try to recreate the operating machine speed (correct?). Perhaps in a vacuum pit?

If that's the kind of balancing you're doing, I would suggest it is not a rigid rotor. Because all that trouble to recreate operating speed is not required for a truly rigid rotor... a rigid rotor can be balanced at any speed below running speed.

ISO 19499 was approved with corrections.