High-performance modern machinery functions at extraordinary speeds. This means that design and material integrity are crucial to operational reliability and the safety of human operators. Barbour Stockwell, Inc. Barbour Stockwell, Inc. (BSi) in Woburn, Massachusetts provides the right spin test equipment for qualification, low cycle fatigue and acceptance testing as well the research and development testing necessary to evaluate new materials or designs or to confirm design calculations.

Broad portfolio

BSi’s has a broad portfolio of spin test facilities designed and produced to satisfy your specific requirements. Its expertise and many years of experience are a guarantee for economical and reliable tackling of a wide range of test requirements. BSi has provided facilities for overspeed testing and burst testing, including low and high-cycle fatigue testing. These facilities allow for tests at temperatures ranging from 80 Kelvin to 800°C in spin chambers with a capacity for rotors ranging up to 2800 mm and 12 tonnes and moving at speeds up to 200,000 rpm.

Electric and air turbine drives

Air turbines are a simple, elegant means to generate very high speeds. They are also compact and allow for very fast drive changes to cover a broad range of speeds. Moreover, they are typically less costly than electric drives, especially if there is already an air system in place. Electric motor drives, on the other hand, involve fewer energy conversions and therefore yield higher overall efficiency. Moreover, energy is returned to the mains during braking so that net energy consumption is basically reduced to only the parasitic losses in the system. The electric drive systems are thus far more economical for LCF testing or very large test articles. Finally, there is no need for an air system.

Drive Systems

BSi’s drive systems provide ultra-high rotational speeds with precise speed control. This is the company’s key advantage in conducting its own spin tests or driving the components in other test rigs. All tests are conducted under the precise control of BSi’s TC4 controller powered by its SPIN IV software.

Air/steam turbines

In addition to the tangential turbines historically supplied for spin testing, BSi has developed its own line of Radial Inflow Turbines (RIT) for applications that require very high power at very high speeds. While the inherently robust construction and bidirectional capability of the tangential rotors make them well suited for spin testing, tangential turbines are low specific speed machines; that is, they provide best performance at relatively low power levels. The RIT’s, on the other hand, are capable of providing very high power levels with extraordinary efficiency. The company has delivered RIT drive systems to provide 130 hp at 130,000 rpm and 800 kW at 50,000 rpm.

Electric drive systems

BSi’s high speed electric drive systems comprise high-efficiency motors with sophisticated direct-torque control drives. When speeds greater than that of the motor are required, gearboxes designed and built by BSi are employed. All BSi gearboxes incorporate helical gears for quieter operation and longer life. For higher power levels the gears are double helical to eliminate thrust loads, thereby extending the life of the bearings. Speed control is assured through the company’s proprietary TC4 controller and speed control algorithms. BSi electric drive systems meet all CE Standards and Norms. Moreover, they reduce utility demand charges and introduce less harmonic distortion in the power supply than conventional DC drives. The AC motors provide an efficiency of 90% at base speed and develop their full power at 50% of rated speed.