Occasional warnings come up suggesting that graphite packing conducts electricity and causes electrolysis. Measuring wet packing with a multimeter, both PTFE flax and graphite packing showed significantly higher resistance than ordinary tap water—about 3,000-ohms resistance for Western Pacific Trading’s PTFE flax packing, more than 2,000 ohms for the company’s graphite-and-PTFE-blend packing, and 1,700 ohms for tap water.
“We sell graphite packing, and I’ve never seen the graphite damage a stuffing box,” says Jimmie Harrison, owner of Frank and Jimmie’s Propeller in Fort Lauderdale (www.fjprop.com). He says the more-noble Monel shaft would outlive the bronze stuffing box if damage were to occur.
Neither Gaston nor Laurain have seen damage they could attribute to graphite packing.