Automotive industry plants must run lean. And that's true not just for work-in-process, but for maintenance operations too. If these tasks are inefficient or machinery can't be serviced quickly because parts can't be found, workflow is often disrupted. And that's exactly the situation that automotive industry supplier Siemens VDO needed to confront at its Newport News, Va., plant.

The main assembly area for fuel injectors, says Shari Jourdan, operations support manager, has linear assembly steps and no backup machines if equipment goes down. This situation was a major factor in the decision to revamp the storage systems for managing maintenance, repair and operations (MRO) parts.

"In a linear operation—such as our major assembly area—if one part of the process breaks down, everything shuts down," says Jourdan. "In this environment, it's critical to be able to find [MRO] parts quickly, get the machines back up, and get the process back on line."

The Newport News plant manufactures the company's fuel injectors as well as other fuel system components. It became apparent that new systems were needed to ensure parts were easily accessible. In addition, inventory accuracy for the MRO parts need to be improved too.

That led to the installation, says Jourdan, of seven vertical lift modules (VLMs). Each is located close to the point of use of the MRO parts. In addition, responsibilities for equipment and parts among maintenance engineers were redefined.

Placing the VLMs at the point of use eliminated the central storage scheme used earlier, says Jourdan. As a result, the time required to retrieve MRO parts was reduced considerably. In addition, the small footprint of the VLMs opened up approximately 2,000 square feet of floor space for manufacturing.

"One key goal of the deployment was to bring the parts closer to the places they get used, so that parts are easily accessible when needed," says Jourdan. "The new software system that manages the inventory also has better search functionality than the system we had before."

The inventory management software that runs the VLMs (Remstar) does all the locating, retrieving and recording of parts requests and transactions. Each unit is an enclosed system of vertically arranged trays, an extraction platform, and computer- driven controls. What's more, the VLMs have been integrated with the enterprise resources planning (ERP) system used by Siemens VDO.

"It's a more well-defined process for obtaining these parts," says Dean Major, logistics manager for the plant. "Anyone accessing a VLM can use the search function to quickly find and obtain a part. When that's done, the software interfaces with our ERP system and the reorder point logic. It's a seamless integration that supports accurate inventory control."

Previously, says Jourdan, the central storage area had manual cabinets, with a DOS-based software system for search and inventory management. Trouble was, says Jourdan, the old system lacked the easier search functions of the new software. And since the cabinets were manual, they didn't exert control over which parts could be checked out.

"I'd say the new system encourages parts accountability, rather than strictly enforcing it," says Jourdan. "When it brings down a shelf, you have access to everything on the shelf, so you could take out more than needed for a given task. But there is really no benefit to doing that, and it's also very easy to put things back. So we are getting better inventory accuracy with the new system."

The new units are highly space efficient. About 20 feet tall, the VLMs use otherwise wasted overhead space and minimize the storage footprint. Furthermore, space within the storage units is maximized. Items are stored to make best use of space within the equipment.

Three VLMs are located in the main injector assembly area. Four other areas also have a unit. All told, the VLMs contain about 8,500 parts such as motors, valves, cylinders, cables, sensors and custom tooling.

Another storage area holds just over 300 large parts such as pumps that do not fit into the VLMs. This large item area does not have automated retrieval equipment, but the inventory is managed with a software system.

Finally, another storage and inventory management solution holds perishable cutting tools used in the screw machining department. This system only retrieves the requested part, rather than an entire tray, tightly controlling which parts are checked out.

According to Jourdan, there is more to the revamped MRO approach than new equipment and integration to the ERP system. Process improvements also were made to maintenance procedures.

Specific manufacturing engineers now are responsible for the MRO parts management for the machinery at the work centers they oversee, says Jourdan. Previously, engineers might have been responsible for MRO parts for larger areas of the plant. "By breaking the spares responsibility down into smaller groups of equipment, and actually assigning that to the process owner responsible for that equipment, it makes the process more manageable. It also promotes a higher level of accountability," Jourdan adds.

The process change required some corresponding changes in the way MRO parts data was organized with the ERP system. For instance, the ERP's data field structure is now configured so that certain equipment groups, as well as the engineers for those groups, are associated with certain MRO materials. Before, Jourdan says, the system had text-based notations identifying process owners, but no easy way to associate process owners with equipment and materials.

In deploying the VLMs, the first unit served as a pilot project. Some screen customizations were made, and inventory for the MRO parts needed to be taken down to zero and then reloaded to properly implement the purchasing and materials management processes for VLMs. It took about six weeks to deploy the first VLM, says Jourdan, including setting up the management software, but subsequent units were rolled out much quicker.

The new equipment and software as well as physical changes to facility layout are well complemented by the people and process improvements, says Major. In fact, the success here was also due to lean manufacturing efforts and use of Six Sigma techniques to maximize performance. Bringing it all together opened the door to improvements.