July 2009 | Case Studies | DC Solutions

Warehouse Automation: Siemens Sorts It Out

Tags: Warehousing

Siemens sees labor cost and floor space savings, significant improvements in employee ergonomics and morale, and a fast return on investment from its new materials handling system.

A s a leading supplier of postal and parcel solutions, Arlington, Texas-based Siemens operates one of the largest postal sortation equipment manufacturing plants in the world. The Infrastructure Logistics manufacturing site in Dallas/Fort Worth, Texas, handles postal sortation equipment parts, pieces, and installation kits, and holds the finished goods for shipment.

When Siemens decided to improve receiving, quality assurance inspection, put-away, and picking at the plant's warehouse facility, it looked for third-party help. After a detailed selection process, it chose materials handling systems integrator Diamond Phoenix, Lewiston, Maine, and Richards-Wilcox, a manufacturer of overhead power and free conveyor systems based in Aurora, Ill., to handle the automation upgrade. Together, the companies analyzed the facility and designed an automation system that would increase overall efficiency and inventory control.

The system includes horizontal carousels, an overhead monorail conveyor, a roller conveyor, pallet rack, flowrack, and vacuum fluorescent display controller. It handles three types of Siemens warehouse products: small items in totes, regular 48-inch by 48-inch pallets, and oversized pallets.

Implementing an automated tote conveyor and carousel system boosted productivity in handling small parts at the warehouse. Previously, warehouse workers picked parts using a paper-based method and placed the parts into totes that they often had to push across the floor to their destinations.

Siemens wanted to keep these totes, but the model had been discontinued and the design mold had been sold off from the original vendor. Diamond Phoenix was able to research and track down the tote pan mold from an archive and had 1,000 new totes made for Siemens, keeping the operation uniform and consistent.

"We identify the old totes by the wear they sustained being pushed across the floor," says Michael Savoldi, manufacturing engineering manager for Siemens.

Items are received through induction and placed into totes for quality assurance (QA). Once items are checked for quality, they are set on conveyors for the monorail to pick up and deliver to the appropriate warehouse area. Items can be moved to one of four places: horizontal carousel pods, kitting stations, shipping stations, or directly to manufacturing. Most of the items are sent to one of the three pods of horizontal carousels where they are stored until needed to fill production orders.

Orders come into the warehouse from the manufacturing plant, located one-quarter mile from the warehouse, via SAP order. From there, orders move directly to the pick queue manager, who distributes them based on priority. An operator picks the material, places it in a tote, then marries the tote to the item when the SAP paperwork is scanned before it is placed on the conveyor. Diamond Phoenix software tracks the tote's location and the last place it was scanned on the overhead conveyor system.

Siemens chose yellow monorail carriers and horizontal carousel totes because the color lifts worker's spirits and creates a pleasant working atmosphere.

SPECIAL DELIVERY

The Richards-Wilcox overhead conveyor acts as a delivery device for totes. The conveyor maximizes floor space, using several elevation changes to clear equipment and machinery. Carriers have a 50-pound capacity and are spaced on eight-foot centers. Totes are loaded automatically onto the first available empty carrier at the four load points—QA plus each of the three carousel pods—and unloaded automatically based on the tote ID destination entered by Siemens.

There is no need to stop the overhead conveyor while totes are being picked up. If the loaded tote is unable to divert at the assigned destination, or fails for any reason to unload, it is conveyed to receiving and automatically unloaded. An operator then determines whether to assign a new destination or handle the tote manually.

The unload stations are designed to automatically take the tote off the moving overhead conveyor carrier. For the carousel area, once the tote clears the carrier, a transfer moves the tote to the accumulation roller conveyor leading to the work station. For the kitting diverts, a short section of powered roller moves the active tote on to a gravity-run out section of conveyor where the totes are accumulated. Pickup stations have a transfer to place the tote in front of an empty carrier on the overhead conveyor and a stop to hold it in place as the carrier picks it up on the fly.

Totes inbound from receiving to the carousel area are scanned upstream of the first pod and diverted to the required pod for replenishment. The totes are automatically diverted and accumulated by the end of the carousel workstation.

When operators are ready to replenish parts, they pick the six queued totes off the inbound accumulation conveyor and place them on the work station. Three pods of three carousels each hold the parts until called for.

Operators place parts from the carousels destined for the kitting operation into totes. When the totes are complete, operators scan the tote ID, the SAP-generated paperwork, and a destination card. This information is written to an electronic file in the receiving area and the destination of the totes is sent to the Diamond Phoenix programmable logic controller. The tote is pushed onto the takeaway conveyor and transported to the overhead conveyor pickup station. The station transfers the tote for pickup on the first empty carrier.

YOU'VE GOT TO BE KITTING

After picking, operators place the totes on the outbound conveyor pickup transfer using the Diamond Phoenix material handling controller and scanner to capture the tote ID. Then they enter the destination. The tote is automatically transferred to the overhead conveyor system and delivered to the kitting areas.

Next, the tote bar code is scanned as it enters each kitting area. If the tote needs to be diverted in that area, it is tracked until it reaches the proper point, where a stop actuates the overhead conveyor carrier to unload the tote. The overhead conveyor never stops moving. Once the tote is clear of the carrier, it is conveyed and accumulated for processing.

At receiving, pallets are unloaded and those containing parts that require QA inspection are placed on the pallet accumulation conveyor, which feeds six spurs in the QA area. Operators take the parts requiring inspection to workstations for testing. When a SKU completes testing, the pallet is transferred back to the accumulation conveyor and moved to the receiving dock. An operator then places the pallet on a pickup-and-deposit stand to be put away in the pallet rack.

Through the use of horizontal carousels, a monorail, and a conveyor, materials now flow through the Siemens warehouse with ease.