Overview: StreamTech implemented a small-item sorter for a combination of small boxes and padded mailers to help a customer increase accuracy and save labor.
Small Item Sortation Challenge
A customer desired a small item sortation system to sort a variety of small packages at medium to high speeds. The existing hand-pack operation was to remain and the small items needed to be sorted to shipping gaylords. The packages consisted of a variety of boxes and mailers. In the old operation, employees placed the items on a slow moving belt and the products created large piles of volume, which needed to be hand-sorted at the discharge of the conveyor system. In particular, due to the way the mailers were stuffed the package had open areas of exposed pressure-sensitive glue, not sealed completely. The existing roller conveyor system allowed the packages to touch and thus adhere to one another, creating logjams. This sticking would be sure to be a challenge for any future automated sorting system. When presented with this challenge StreamTech engineers came up with a simple-but-effective method using “targets” on a belt conveyor as the basis of the small item sortation system to give operators a window to place product, thus eliminating the chance of items sticking together and also simplifying the induction system requirements. Now the items were able to be pre-spaced, and ready for scanning and sorting. Sensors and smart logic help check to make sure that any packages placed too close are safely shunted through the system rather than causing a jam or a mis-read. A simulation was provided to check that the last few pack stations would still be able to induct during high volume periods and would not be constrained.
Scanning and Induction
Items are placed on the white striped target areas permanently affixed to the belt. The item is scanned and the response indicating the lane assignment is returned from the customer WMS. Because the response time was so long, it was agreed to provide a 2nd scan station and ensure that the destination is updated, after that the package is tracked conventionally. Camera style scanners provide great read rates and the ability to discern 2D barcodes in the future. More importantly, the cameras do a great job with the labels that may be wrapped around the front or sides of the softer packages. Multiple scanners are used to cover the width of the belt at the depth needed for the multiple package heights. Real-world read rates are in typically in the 99.5-99.7% range.
Flexible Sortation Software
The SCS software allows the area supervisor to assign lanes to the appropriate shipping destination. The software estimates the fill level of the gaylords and suggests when the operators can remove them; the operators disable that lane while the movement is taking place. A lane destination may have multiple gaylords assigned to it so the system is able to switch over easily when a gaylord is pulled out of service. Configurable business rules help the operators by making the system think ahead to save people time. The system has multi-level user security and records production metrics and any exceptions for analysis later. Because the cameras are ethernet-based it is also possible to troubleshoot them remotely as well.
Narrow Belt Sorter
The TGW NBS90SP is ideal for small item sortation; the narrow-belt design operates quietly, smoothly delivering packages to the gaylords. Noise levels on the entire system are extremely low. The sorter’s narrow belts each have their own tensioning device which ensures maximum life for each belt. The sorter is extremely accurate due to the zero relative motion of the product with the belts. The tight centers on the belts handle very small product. The diverts are normally stopped, and start-up when a sort is commanded. The system easily handles peak days of 30,000 packages or more and up to 3,600 packages per hour.
- Eliminate Hand-Sort Labor
- Eliminate errors to to hand sorting
- Packers can work autonomously
- Machine verification of every order
- Better ergonomics (60″ tall gaylords)
- eliminate errors due to stuck packages