The column's packing support tray has two critical design parameters.

1. The tray strong enough to support a wetted packed bed typically this is calculated used dry packing weight +10% liquid holdup.

2. Allow gasses to flow unimpeded through the bottom of the packing support tray, not to disturb normal laminar flow distribution. A packing support tray is usually categorized by the open area it allows in reference to the column's cross-sectional area.

The convoluted Design. to allow for open areas of greater than 100% a convoluted design is typically used as shown in the images on this page. A typical convoluted design will have 120% open area while maintaining structural integrity. These designs also provide much better strength by geometry, allowing for fewer support members in the column.