Structurally intact ceramic matrix composite (CMC) bearing after four-stage testing and pump disassembly
Sealless pumps use sleeve bearings typically machined from carbon graphite or sintered silicon carbide (SiC). The hardness of these materials allows them to withstand wear during the pumping of aggregate solid media. However, the limited dry-running performance of carbon graphite relegates its use to systems with minimal loads and constant lubrication. While SiC bearings have excellent tribological performance, wear resistance and chemical resistance, they often suffer from catastrophic brittle fractures as the bearings cannot absorb shocks and vibrations encountered during pump upset conditions.
In 2014, Engineers at the JX Nippon Chemical Texas Inc. in Pasadena, Texas, initiated performance testing of ceramic matrix composite (CMC) bearings reinforced with carbon fiber. The company wanted to reduce downtime caused by frequent replacement of OEM monolithic carbon graphite bearings, which had consistently failed as a result of vibration fractures during cavitation and dry-run conditions. The Engineers at JX Nippon believed the CMC’s thermal and mechanical fracture resistances would increase bearing resiliency during pump upset conditions.
Download the whitepaper to learn more about the rigorous testing and results that were revealed after four phases of testing.