The following case study describes and explains a specific troubleshooting exercise on pump cavitation. The detection, surveillance and deep understanding of cavitation parameters were set up in collaboration with the pump OEM in a very effective way for the Customer, OEM and the Wi-care analyst.
For the Customer: easy detection, fast diagnosis and monitoring of the defect until planned shutdown with low upfront investment and lower costs than manual/traditional monitoring.
For the OEM: high performance troubleshooting system, easy to install at low cost collecting data over a long period of time taking into consideration various production parameters. No need for an after sales team to attend on site.
For the analyst: early detection, instant trend data and 24/7 protection, higher confidence in action delay without any travel or measurement time spent
Equipment, plant overview, Context
The Gas Storage and Distribution plant is located in Western Europe. The Machine Train in question is a single stage pump with a double suction. Pump operating in a distribution network. There are others pumps with various flow/pressure parameters also connected to this network. The suspect pump exhibits cavitation issues in some production configurations. The Pump OEM agrees to collaborate with I-CARE and install Wi-Care vibration and temperature wireless condition monitoring equipment to record and trend the evolution of this pump cavitation in a standard production regime.
Analyst diagnosis and spectrum: A better understanding of Cavitation
The Wi-care system is set up with one sensor on the electrical drive, and two sensors on the pump bearings.
Outlined below is the standard spectrum collected with the Wi-care wireless monitoring system at one of the pump bearings. Display is in acceleration units G PK. The spectrum demonstrates high level of random noise with dominant frequency and harmonics at vane pass frequency.
Wi-care data from 05 June 2014.
Seen below is the data trend table grouping data from the bearing measurement point over the last measurement sample.
Analyst observations on Wi-care spectrum trending
Trend data indicate a high level of cavitation throughout the same production parameters. However, increased levels of cavitation are identified on this pump when different pumping configurations are used. The analysis of vibration trend data and the comparasion of spectrum over time allows us to easily identify the precise critical configuration causing the excessive cavitation issue. Collaboration with the OEM contribute to many improvements in the pumping configuration. Wi-Care measurement allows the OEM technical team to check continously, (and remotely) the benefit of every configuration change in order to validate it.