Expander for let down applications undergoing durability testing

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Durability testing of the third generation RadMax gas expander is underway to determine its expected life span, lubrication requirements and to help establish maintenance and overhaul schedules. The testing program mimics aerospace procedures that call for the breakdown, inspection and wear measurement of the expander’s components at 100, 500 and 1,000 hours of continuous running intervals.

The RadMax gas expander is being developed to replace pressure regulation and other throttling type valves currently used in air conditioning / refrigeration, natural gas, steam and other pressurized gas applications. A positive displacement device, the RadMax gas expander is capable of capturing a portion of the original gas compression energy normally lost by the throttling process and converts it into torque, which in turn can be used to generate electricity or power other shaft driven devices.

The testing program has reached the 500-hour mark of continuous running with no measurable wear or decrease in performance. Durability testing is continuing under an increased pressure and load until the 1,000-hour mark is reached. This will trigger the breakdown and final inspection of all expander components and will include wear measurements of all applicable components and surfaces.


Paul Porter, RadMax Chief Technology Officer, states “Expander disassembly and inspection at 100 and 500-hour intervals showed no visual or measurable component wear with all measurements still within manufacturing tolerances. This is very encouraging. The expander design is proving to be very robust and there is no reason to believe that it will not easily meet the 40,000 hours before overhaul, design goal”.