Blackstone recently completed the retrofit of a 1976 Dresser Rand 5.5 RDS 6 (southwest Industries- Ingersoll Rand) train for GE Industrial Solutions, Energy Management.
The exchange of engine drive for electric motor drive with VFD is common in industry for many operation and maintenance reasons. Time and technology often deliver good technical reasoning and commercial need to update long running fleets or add operational flexibility. The implications of this ‘exchange’ are not without some deep considerations to the Torsional Analysis of the train and the transmission of torque forces at the coupling and dampening with a flywheel. A detailed review must be completed to create equivalent shaft dimensions, this is of course more challenging in machines that have seen many years of use and run in various process conditions with modifications and inconsistent maintenance philosophies. Modeling the machine over various working conditions and speed ranges requires steady state analysis of torsional natural frequencies and relevant mode shapes and critical frequencies. This goes beyond the standard sizing of componentry, but is critical evaluation to manufacture useful long term solutions.
Blackstone worked with its engineers and Compressor Service Technology (CST) to evaluate, design, create specification, manufacturing drawings and implement a strategy for the customer for a full train solution. The successful offering proves that maintenance has many levels and even the biggest companies in the world need help to deliver solutions that don’t just stop at their shaft end. Blackstone is proud to deliver competency through collaboration and technical excellence.
