Trials of fluid-sealing solutions provider Klinger Mzansi’s dry running mechanical packing seal for centrifugal pumps have revealed that the carbon-based braided yarn solution lasts up to three times longer than other mechanical packings.

Klinger Mzansi packings product manager Gareth Langton tells Engineering News that the locally designed and manufactured solution has not failed since trials started in July last year in a boiler feed application, which he notes would normally require a new packing every three to six months.

The packing has also successfully been applied to slurry and chemical process applications. He points out that the material used to fabricate the packing makes it safe to use in hazardous applications, as the material is chemical-resistant and not flammable or toxic.

Further, Klinger Mzansi’s packing solution simplifies pump maintenance, as the unit can be changed on site, eliminating the need to remove pumps from site to conduct maintenance.

Langton states that the success of the packing is attributable to the unique carbon yarn used in the fabrication of the solutions, which he notes provides the solution with improved tensile strength and thermal conductivity properties.

“In some cases these packings were more abrasion-resistant than Kevlar yarns and significantly outperformed polytetrafluoroethylene-based yarns.”

He adds that carbon yarn technology is often regarded as too costly by end-users to warrant its being installed on pumps. However, Klinger Mzansi acquired the yarn at a cost-effective price, resulting in a carbon yarn packing solution that is about 30% cheaper than other carbon yarn solutions, comparing favourably in price to packings made of other materials.

The yarn used by Klinger Mzansi is imported; however, Langton notes that the material is treated and braided locally by the company, using new machinery it designed and manufactured in South Africa specifically for the development of the carbon yarn mechanical packing, which is available in a square cross-section braid from 5 mm to 25 mm.

Klinger Mzansi began research and development for its carbon braided packing in early 2013, which Langton points out involved a significant amount of research into different yarns and technologies. In mid-2013, the company discovered the yarn it now uses in its packing and successfully braided the material at the end of 2013.

The packing is likely to be officially launched early next year, he concludes.