Structural steel pipe racks typically support pipes, power cables and instrument cable trays in petrochemical, chemical and power plants. Occasionally, pipe racks may also support mechanical equipment, vessels and valve access platforms. Main pipe racks generally transfer material between equipment and storage or utility areas. Storage racks found... Found on http://en.wikipedia.org/wiki/Pipe_rack
Racks or frames are often used to store tubulars horizontally in yards and or offshore decks, and when transporting them offshore. Pipe racks are also used where stands of drill pipe are stacked vertically in a derrick ready for use.
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