Specialised polymer manufacturer Vesconite Bearings believes that the experience it has gained from KwaZulu-Natal sugar mills will prove instrumental in ensuring the success of its multi- continent sugar strategy and grow the company’s revenue from new markets.

Vesconite Bearings technical sales representative Eddie Swanepoel shared his experiences of successful applications of the company’s products with US sugar producers in a visit to the American Society of Sugar Cane Technologists’ (ASSCT’s) joint meeting, in New Orleans, from June 14 to 16.

There, the polymer manufacturer also learned about the bushing difficulties of US sugar producers, which Vesconite Bearings aims to use as a source for prototype trials to develop new applications, which will further broaden the potential uses of the company’s product range.

“Vesconite Bearings’ polymers and wear components were well received at the ASSCT. Several US sugar mill operators visited our stand and discussed actual problems that they were experiencing. Four sugar mills have initiated polymer pump bushing and hanger bushing testing.”

Swanepoel adds that those attending the meeting were encouraged that mills in North Dakota, Idaho, Florida and Louisiana are already using Vesconite and Vesconite Hilube polymer wear components.

Polymer Benefits
Swanepoel highlights that polymer bushings, which require limited lubrication and have a low coefficient of friction, often replace bronze bushings in sugar mills, as bronze bushings need to be greased with food-grade or bitumen grease.

Greasing costs can be substantial – as the number of greasing points multiplies, as the number of machines in a large mill and the frequency of required greasing increases. The costs of labour, lubrication equipment and grease further increase the cost of greasing.

He notes that the largest cost associated with greasing, however, is equipment downtime if greasing is not performed or carried out incorrectly. For the sugar industry, the concern is that unlubricated bronze bushings will seize in a few minutes, subsequently resulting in downtime if bushings have to be replaced and shafts resleeved or machined. “For the South African sugar industry, the sugar production season is eight months long and any downtime reduces production and profitability.”

Costs associated with using bronze bushings are also often high, owing to bronze typically not being a food-grade material, with special, more expensive soldered bronzes required.

“In addition, bronze theft is a problem, as a result of the scrap-metal resale trade. Sugar mills are, thus, attempting to avoid the problem of bronze bushing theft, which can also lead to high costs.

Vesconite Bearings supplies all 12 of the existing KwaZulu-Natal sugar mills with a variety of components for bushing and wear applications, including underfeed rollers, hanger bushings, pump bushings, vertical crystalliser support bushings, feeder table bushings, mill housing side plates, long- travel-crane wheel bushings, ash settler sprocket bushings and lime bucket bushings.

Swanepoel notes that the Vesconite, Vesconite Hilube and HiTemp 150 polymer components were particularly in demand last year, owing to the effect of the drought on sugar operations in South Africa. He explains that the drought resulted in less water being available for milling and more sand being in the production process.

As the polymer components that Vesconite Bearings produces require little lubrication and are extremely wear resistant, many of the sugar mills that remained in operation during the drought benefited from the advantage of converting to polymer bushings to avoid maintenance breakdowns caused by abrasive materials and a lack of water.

“The knowledge gained from hard-wearing African sugar applications has been essential in converting other relatively new markets to using our products.”

Swanepoel points out that US sugar millers produce sugar from cane and beet, with sugar produced from cane in the more tropical regions and sugar produced from beet in the north of the US.

“Many of the Vesconite, Vesconite Hilube and HiTemp applications that have been proven successful in South African sugar mills were well received by the cane and beet sugar mills in the US. In addition, the beet sugar mills, owing to their different processing methods, may prove to have additional wear applications in which Vesconite, Vesconite Hilube and HiTemp 150 polymers can be used.”

He adds that, in the local South African sugar industry, farmers own their own trailers and buy Vesconite and Vesconite Hilube components themselves. In contrast, in the US, the sugar mills often support sugar farmers by providing trailers for production, with mills having fleets of 50 trailers in some cases. As a result, the sugar mills, rather than the farmers, buy the S-Cam and suspension bushings. “This structural difference will increase the number of applications that will be marketed to the sugar mills.”

Vesconite Bearings supplies sugar producers in South Africa, Tanzania, Malawi, Kenya, Mauritius, Zimbabwe, Mozambique and Sudan and is starting to make headway in the US, supplying sugar cane and beet sugar producers.