| 摘要 |
<p>A rotary drying drum (10) for a moving web (12) includes a stationary heater drum (23) positioned coaxially within the drying drum (10) such that the drying drum rotates around the heater drum (23). The heater drum may be supplied with steam via a hollow drying drum shaft (21) without the use of high pressure steam joints. Heat from the interior heater drum (23) is transferred to the rotary drying drum wall (11) by a thin layer of suitable heat exchange fluid (30) confined to the annular space (25) between the coaxial drum walls. A low molting point bismuth/lead/tin alloy is the preferred heat exchange fluid.</p> |
