Processing Parcels

The Postal Service also has turned its attention to speeding up the processing of parcels, which make up a little over one percent of mail volume. Small parcel and bundle sorters were introduced in 1988, mechanizing one of the most labor-intensive operations in the Postal Service. The small parcel and bundle sorter uses a conveyor system with four to six induction stations where operators face and key mail based on ZIP Code. Then, conveyors transport the mail to specific bins for delivery or further processing. Beginning in 1999, feed systems were added to the sorters, reducing labor costs.

In 1992, the Postal Service began to deploy package barcode sorting systems to process prebarcoded parcels and to apply barcoded labels to nonbarcoded parcels. In 2001, singulate, scan, and induction units were introduced. These units send parcels, one by one, through a unit that measures and weighs them, and then through a scanning tunnel that reads the barcode. Next, parcels are fed automatically onto the sorter at a rate of more than 5,000 per hour.

In 2004 the Postal Service began to deploy the automated package processing system (APPS), which uses an OCR/barcode reader/video coding system to sort more packages more quickly. Deployment of the APPS, which can process up to 9,500 parcels per hour, continued through 2006.