Support plates are provided for physically supporting the cumulative weight of the random and structured packing as well as operating liquid hold up.
Support plates are shaped and designed to provide maximum open area such that there is minimum resistance to gas flow. The factors that influence the choice and design of the support plate are the column diameter, design load, packing type, liquid hold up and systems corrosivity.
Gas injection support plates provide separate pathways for gas and liquid and therefore it reduces pressure drop across the support plate. These are the most preferred type and are used in the majority of applications. Light duty support plate is used only for very small columns and where hydraulic loading is not severe.
All support plates rest directly on a support ring since the weight of the packing is sufficient to keep the support plate in place. If required however, they can be clamped to the ring.
Bed limiters are normally recommended for metal and plastic random packing and are designed to withstand an up thrust. The openings sizes can be varied to suit various packing sizes and the beams can de designed to support man-load. The bed limiter can be clamped on to a support ring or rests on the tower packing where no support ring is available.