摘要 |
<p>A storage tank for liquid media has a floating cover which is filled with plastic insulating foam and has a peripheral seal against the cylindrical tank walls. The seal consists of a perforated hose which is bonded into a semicircular rim of the cover and is also filled with plastic foam. To make the foam of both cover and seal conductive for static electricity it is filled with particles of graphite. This prevents the accumulation of static electricity by friction of the seal against the wall and of the fluid against the cover, which may produce explosion if the fluid is oil, petrol or a liquefied light hydrocarbon. The hose can be easily cut to length to make it suitable for different tank diameters.</p> |