Original Article found here: http://www.flowserve.com/files/Files/Literature/ProductLiterature/Pumps/fsg-ss-005-e.pdf
The Challenge: An ammonia /urea facility experienced severe reliability issues with its Benfield1 solution system pumps. Shaft failures were occurring every 6-9 months, costing the plant hundreds of thousands of (U.S.) dollars in maintenance and downtime costs.
The Solution: Flowserve installed an intelligent diagnostics and optimization system consisting of two IPS APEX™ units and a local convergence unit with visualization and communication capabilities. Embedded with software developed with Flowserve system and pump domain expertise, the IPS APEX units continuously monitor operating parameters of the Benfield pumps. The units also transmit the data to an on-site control room where operators can enact prescribed control measures at the first sign of upset conditions.
An ammonia/urea facility had recurring problems with its two Benfield solution pumps. Facility engineers suspected that gas formation within the system was the cause of the shaft failures; however, short-term monitoring of the pumps had not detected evidence to support the hypothesis.
After 12 years of battling the problem at consider- able cost, the facility engaged Flowserve to verify the root cause of the failures and recommend corrective action. Drawing upon their considerable system, pump and diagnostic expertise, Flowserve engineers developed a systematic, phased approach:
- Step one was to continuously monitor key param- eters of the pumps for a period of time.
- Step two was to conduct a thorough field assess- ment including interviews with essential plant personnel.
- Step three consisted of analyzing the available data and information gained from the site assessment and equipment monitoring to identify the cause and make recommendations to rectify it
Upon completion of the study, Flowserve concluded intermittent aeration was indeed the root cause of the premature shaft failure. They found the aeration induces significant vibration which eventually causes the shafts to fail due to fatigue.
Taking an integrated approach, Flowserve recommended installing two IPS APEX units, multiple sensors and a convergence system to detect the onset of aeration. IPS APEX is an intelligent pump monitoring, diagnostic and control system embedded with intelligence derived from the extensive pump system expertise of Flowserve.
The system utilized highly specialized software developed by Flowserve which included a sophisticated data acquisition system and an application-specific aeration detection algorithm. It was used in conjunction with a convergence unit for visualization, communication and alarm generation.
By monitoring key parameters the system was able to detect the early onset of aeration. An alarm alerted pump operators to take corrective action.