Pipe racks column spacing

Such equipment as drums and deaerators is often located above pipe rack columns. To avoid wasting valuable rack space with the large support columns, the inside face of the pipe rack column must line up with the inside face of the equipment support column, as shown in Exhibit 11-26. This approach also allows the feed-water outlet piping to run venically down to the pump before the expansion loq> is added. 

Multielevation piperacks are usually needed to handle all the required services for piping, electrical, utilities, and instmmentation. The two-level rack is one of the most common but three-level ones are also used. The utility lines are usually mn in the upper level and the process lines in the lower levels. The larger-diameter lines are located to the outside of the rack to be closest to the column supports. Access platforms are required at the battery limit to provide operators access to the block valves and blinds. If long mns of hot pipe are required, a portion of the pipe rack needs to be dedicated to an expansion loop. A horizontal space in the piperack is provided for a set of lines to be flat-turned into a set of expansion loops with the large pipes located on the outside. AH of the pipe turns are in the same horizontal plane, which is an exception to normal piping practice. A flat turn takes up and blocks space for other pipes. Flat turns are generally only made from the outside of the rack to minimize this blockage. 

Alternative pipe rack expansion of the individual vels can be accomplished by adding a cantilever earn as required on the outside of the column. The nly problem with this approach is that, if not planned >r, the vertical risers commonly found outside the ipe rack use a considerable amount of the space of le extension, as shown in Exhibit 11-13. 

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