Downcomer bolting bars

Tray support weights Include downcomer bolting bars as well. 

Trays may be clamped (Fig. 7.2a) or bolted (Fig. 7.26) to their supports. The overlap of the tray plate on the support is usually V4 to 1 in (86). Similarly, downcomer panels are usually clamped (Fig. 7.2c) or bolted (Fig. 7.2c ) to the vertical downcomer support bars. The downcomer support bars are welded to the shell. The fastening of downcomer panels to their supports should permit some on-site adjustment for ensuring correct setting of clearances under the downcomer. 

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