D shape elements are heating elements formed from round to 'D' section and then formed to round diameter to achieve a cyhndrical format. They are compacted to a much extreme density. This process increases both heat transfer ability and insulation value to the di-electric. The greater insulation value accommodates higher watt densities. These heaters produce more wattages compared to conventional heaters and can operate at higher temperatures. Maximum operating temperature is 650°C. The life of 'D' shape elements is directly related to its internal operating temperature. Denser and more uniform compaction of the di-electric provides greater heat transfer to the sheath. This, combined with more efficient heat transfer to the surrounding metal through intimate contact with the wall of the bore, permits the 'D' section elements to run substantially cooler resulting in better life. Better heat transfer means less power consumption to maintain the set point temperature reducing operating costs.
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