As manufacturers, we are always looking for ways to make things run faster, cheaper, and simpler. Often, the approach we take involves reassessing the production elements within the plant that impede the system flow. In such an analysis we take stock in the operation as a whole in search for efficiencies in the parts. In short, to enhance productivity while responding quickly to rapidly changing customer demands, we try to take full advantage of the resources available to our plant. In doing so, the modern manufacturer strives for total enterprise resource planning (ERP) that ensures all plant elements are in synch with each other. In the evolution of ERP as a manufacturing concept, the idea of work center management has come to the forefront as a place of greatest gains in efficiency.
While pull-production techniques certainly strive for just-in-time (JIT) manufacturing modes, efficiencies that might be gained in other plant operations are sometimes lost in expensive set-ups and in-direct labor costs associated with non-productive shop floor time. To overcome these negatives, the lean cell was developed to take advantage of repetitive unit production and physical plant space. Based on sensible ergonomic principals, in the lean cell operators function in very close proximity to each other-so close that they can merely hand each other piece units. In the classic lean workcell, an ERP operation can maximize production efficiencies through some of the most basic lean principles:
- Continuous Flow: Through the use of shadow boards for tools and the pre-assembly delivery of material to the cell, the lean workcenter eliminates most non-value added operator movement (i.e., in-direct costs). In other words, the lean cell becomes a place of efficiency where a value-add to value-add operation is realized.
- Set-Up and Reconfiguration Efficiencies: By isolating repetitive production processes to a single space, set-up and cell reconfiguration costs and times are reduced significantly. This results in maximized changeover with minimized downtime in a relatively uninterrupted plant flow.
- Improved Quality: With the opportunity for immediate feedback via quality inspection, the lean cell reduces waste and enhances continuous improvement-a lean production principle. In addition, through the use of simple, lean machines in the cell, the replacement of malfunctioning devices is usually quick and easy.
- JIT Delivery: Not only do parts arrive to the cell when needed, but the rapid one-piece (or small) lot flow of the lean cell means pull-production is maximized at every step along the system flow. In addition, non-cyclical work is performed by support personnel located outside the cell. All of these factors aid in the elimination of both inventory and work-in-progress.
Ultimately, the proper use of a lean cell system in an ERP operation cuts production cycle time significantly. From the receipt of the order by the order entry clerk to the shipping of the finished goods out of the plant, production time is reduced and JIT pull-production is enhanced. In addition, with in-direct costs minimized through the ergonomic continuous flow design, lean cell manufacturing enhances the all-important bottom line profit margin.