MORGAN ADVANCED MATERIALS: Porous Silicon Carbide for Environmentally Friendly Pump Seals
Morgan Advanced Materials has pioneered a new porous silicon carbide material that is expected to offer very similar properties to the current polymer microbead solution without posing a risk to the environment.
The manufacture of clean pumps used in food and beverage, pharmaceutical, and cosmetics factories is likely to be affected the ban on environmentally harmful polymer microbeads, which are currently used in pump construction but are harmful to sea life. A new microstructure manufactured by Morgan Advanced Materials’ Seals and Bearings business using porous silicon carbide (SiC) is being cited as the answer, offering effective pore forming to help pumps perform longer.
Porous seal rings are vital for long-term pump performance. For companies manufacturing fast-moving consumer goods (FMCG), no contamination is allowed and seal rings must maintain integrity. Friction naturally occurs as the two mechanical seals run against each other; over time, this can affect seal performance and potentially cause leakage. The answer is to add pores, which act as pockets for processing fluid. This fluid acts as a lubricant to substantially reduce friction—but the most popular industry solution currently on the market is not environmentally friendly.
The current solution uses polymer microbeads to create the required microstructure. As reported in a briefing paper to the House of Commons in January 2017, studies have confirmed that polymer microbeads are harmful to sea life; the UK and U.S. governments have banned their use in certain applications already (mostly in cosmetics), with further extensions likely to follow. The ban presents a significant risk to the supply chain in pump manufacture, but Morgan has pioneered a new material that is expected to offer very similar properties to the current solution without posing this risk to the environment.
“In conversations with customers, we’ve been shocked that many aren’t aware of the ban and the danger it poses to their long-term productivity,” said Yifei Zhang, business development manager at the Seals & Bearings business of Morgan Advanced Materials. “Our new porous grade of silicon carbide has been devised to give customers a more sustainable means of supplying pumps that are effectively sealed and lubricated during operation.
“Our new grade offers isolated, round pores on the seal faces which act as ‘pockets’ to retain processing fluid for effective lubrication. This is highly preferable for food or pharmaceutical applications, to graphite-based dry lubrication systems which offer an increased risk of undesired contamination. Morgan’s proven ‘press-to-size’ technology minimizes subsequent machining processes. ‘Press-to-size’ works even for parts with complex geometries, meaning we’re able to manufacture seals to the final tolerance required by the customer.”
Additional details are available at www.morgansealsandbearings.com/poroussic.