He says the heavy fuel-oil is also used to support the coal if there is unstable firing in the burners. “Because a constant-wattage heating cable is used there is a need for temperature control, and controllers are mounted locally on the pipelines,” he adds. The first unit (unit 6) will be commissioned in 2005. He informs that the company has put in a bid to Camden in order to maintain the surface of 64 hoppers at 150 ˚C using electrical trace heating. Further, project engineer Filip Castro informs that the company uses thyristor control in industrial heaters, especially for variations of control of heat. “Eighty per cent of the plants in industry are auto controlled so the advantage of the thyristor control is that it regulates the temperature to the desired heat accurately,” says Castro. He says that, in the past, electrical contactors were used but their disadvantage was that they had only minimum or maximum switching (on – off) and nothing in between. The thyristor is a soft-start controller and has a longer life expectancy. Moreover, customers can gradually raise temperature from minimum to maximum depending on the process in the plant and get 20% more lifespan on their heating elements. Further, Engineering News learns that the company is currently working on a do-it-yourself hot-water kit. “We want to make it possible for the person in the street to be able to install trace heaters,” says Boettiger. He says that the kit, a first for South Africa, and designed by the company, will come with a 30 m roll of electrical trace-heating tape PSB 33 (33 W/pm), 50 m aluminium tape roll, 5 terminations, 4 m roll of fibre tape and an easy-to-follow instruction manual. It is an easy-to-install kit.
“The heat emitted by the tape will be evenly distributed over the pipeline by the aluminium tape,” he informs. Trace heating is already used around the world in countries with colder climates for snow melting and ice prevention. The trace-heating tape used for frost protection and freezing is also used in the refrigeration industry to enable drainage and to be able to open the big fridge doors and prevent them from freezing shut. Boettiger concludes by saying that the challenge facing the industry – like any other industry – is the strong rand. “The strong rand has slowed down import-replacement manufacturing and export manufacturing and this affects us because our customers are involved in these industries,” says Boettiger. He says that, when the company designs and manufactures products it keeps to one of its slogans of keeping the product flowing. “The biggest application for trace heating is keeping the product flowing,” he concludes.