Flats bundle collator

The present invention relates to a method and system for collating a plurality of groups of mail items, each group being pre-sequenced according to prioritized delivery addresses, into a final sequenced set of the mail items from the groups, utilizing the prioritized delivery addresses. More specifically, the present invention relates to a process and system that merges several sequenced bundles of flats mail into one sequenced set of mail for delivery by a mail carrier according to a prioritized delivery address sequence, commonly known as a delivery order sequence (DOS) or walk sequence (WS). A method and an apparatus for collating a plurality of groups of mail items, such as flats mail, each group being pre-sequenced according to prioritized delivery addresses, into a final sequenced set of the mail items from the groups, utilizing the prioritized delivery addresses. Each bundle of mail items is formed into a single input stream of the individual mail items. The mail items are transported along a conveyor system from the input stream to a staging station. The mail items are sorted at the staging station into a plurality of subsets of mail items re-sequenced as an intermediate step to achieving the final sequenced sets. The mail items are then collated and merged into a single output stream from the respective subsets of mail items in the final sequenced set. Portions of the output stream from the staging station are collected in batches in a collection device which maintain the sequence consistent with the prioritized delivery order sequence of the mail for a given carrier route.