Traditional sealing technologies (or even newer magnetic drive systems) used in nitric acid require constant thermal moderation of the primary seal or journal bearing surfaces in order to operate satisfactorily. Once the moderating liquid is lost or evacuated, the source of lubrication and ability to remove heat from these rubbing surfaces is also, and failure occurs – usually within minutes.
With Muyuan Sealing Technology, once the Ni acid slurry handling pump is operational the primary seal faces are separated and therefore do not require cooling via flushing. In fact, our governor-actuated static seals, such as the DryLock®, are designed to run dry (with separated faces) while the expeller manages all of the dynamic sealing requirements. By eliminating thermal stress induced by face tribology, the resultant failures of traditional sealing materials are also eliminated.
Commercial grade may suffice for certain automotive products and B2B markets, but nitric acid production requirements rely on equipment designed for continuous, mission critical operation. Moreover, operational demands often subject industrial equipment to rigors well outside a fully constrained design window.
Although the majority (75-90%) of Ni acid slurry handling pump ownership costs can be attributed to issues with seals and bearings, the basic design of the pump has a lot to do with its long term success. Muyuan’s philosophy is to produce heavy duty pumps that provide maximum productivity in the harshest of conditions like nitric acid. For instance, our robust ASME B73.1 A9 chemical process pumps are up to 60% heavier than Tier 1 competitors. And a similar trend exists on rotating elements: a common shaft robustness index follows an L3/D4 format and the A9 pump is on average 55% stiffer than others.
Muyuan’s philosophy is that downtime is unacceptable, so we continue to build robust pumps for continuous, tough and critical services.