Effective WMS supports lean manufacturing

Enlightened manufacturers have recognised the benefits of going lean to improve efficiency and reduce costs in their production chain. Any business including manufacturingthat relies on the successful flow of materials can benefit from adopting a lean methodology to minimise inventory and optimise handling. Applied in conjunction with an advanced warehouse management system it can deliver significant business and operational improvements.

Lean manufacturing was developed by the motor industry, most notably in Japan where related concepts such as Kaizen and Kanban were devised, to streamline and eliminate wasteful processes. It has since spread to other sectors including aerospace and electronics manufacturing.

Inventory costs money and ties up capital. Reducing it requires less cash and releases capital for more important business processes. The aim should be to receive supplies only when they are needed and deliver finished products as soon as possible. In control

The best WMS help minimise inventory by supporting the efficient flow of materials. They can link with ERP, manufacturing and other systems to ensure stock is ordered and scheduled for delivery only when required and made available for production as soon as it arrives. This allows the manufacturer to reduce the amount of inventory held on site and match delivery patterns more closely to production schedules. Many large manufacturers use this idea to increase their use of off site storage and third party supply arrangements that promote delivery direct to the lineside. This can create shorter lead times and greater flexibility because components can be ordered for and designated to a specific finished product and tracked through the supply chain. It also enhances quality control and customer service through wider choice and product traceability.

Finished goods can be made available for picking and delivery as soon as they have been released from the production area, in some cases avoiding the need for items to enter the warehouse altogether. Loads can be assembled, delivery notes prepared and invoices issued automatically using information generated by the WMS.

Reducing inventory also means less space is needed for storage. Capital equipmentracking, pallets, lift trucksrequirements are reduced and free space can be used for value-adding tasks. Alternatively, the released space can be used for new products to avoid expenditure on larger warehouses or more racking.

Combine a WMS with real time data such as voice recognition devices for even more benefits. 

Take IT to the maximum

In some respects lean is simply the old just in time principle taken to its maximum potential. In extreme cases it might now be possible to remove stock altogether but in practice a manufacturer will hold buffer reserves to ensure production can continue if there are minor disruptions in the supply chain.

If storage costs money so does handling. Moving items into storage and then retrieving them when they are needed costs in terms of space, equipment and time. With lean manufacturing the objective is to eliminate unnecessary handling tasks. This is why cross docking and similar ideas are increasingly popular. But in conventional production environments it still makes sense to look at material flows and handling cycles to see if reconfiguration can reduce the number and distance of movements. For example, fast moving lines can be block stacked or placed in racking at the front of the warehouse so that fewer and shorter movements are required. Modern WMS incorporate analytical tools that provide the evidence to support these changes.

Process improver

Implementing any WMS should improve the inventory management process. Real time data management available by using RF screen based or voice recognition devices, and, potentially, RFID can deliver even more benefits. They reduce errors and handling cycle times by eliminating duplicate management tasks and paperwork. With increased data accuracy many businesses can reduce the frequency of stock taking and release resources for other activities.

The WMS can also help identify where inventory levels are too high or too low. For example, if hundreds of a particular component are held in stock but only a few are picked each week it might make sense to reduce the number held, and free up valuable space, by transferring some to less expensive storage areas.

Inherent to the lean manufacturing concept is the idea of continuous improvement. Small changes made whenever a potential benefit is identified can build into significant gains over time without the delay and disruption associated with the conventional factory reconfiguration. The latest WMS offer the best facilities for effective inventory management and supply chain integration but they are also evolving to provide more effective management and decision support information that will enable manufacturers to use them as part of their business improvement programmes.

Alex Mills is marketing director, Chess Logistics Technology, providers of Empirica warehouse management software with integrated RF and voice technology. Empirica Solutions use RF screen-based and voice data technology to maximise productivity improvements and provide a quick return on investment. And with its unique interfacing capabilities, Empirica integrates easily with existing IT and supply chain solutions.