Theory of constraints comes to complex lean’s aid

Theory of Constraints (TOC) could be coming back into vogue, following years of near exclusive focus on lean thinking. Enterprise software developer Intentia last month launched a TOC production planning system that, it says, will increase throughput, minimise inventory and reduce operating expenses – while also helping to shorten the time to benefit of lean manufacturing. The firm joins several others, like Lilly Software, now part of Infor, that in recent years have espoused TOC, and attempted to make the connection with lean initiatives. It has already implemented TOC at two sites in Scandinavia and claims that projects are underway at three additional sites. “We think there is a resurgence of interest,” says Intentia product director Andrew Dalziel. He claims the firm’s TOC is particularly useful for manufacturers attempting lean in complex production environments. He also suggests that such projects only need reasonable data quality around key constraints to get started. “Discrete manufacturing companies are the biggest market for this,” says Dalziel. “Those trying to go for more make-to-order, with highly changeable order patterns and complex use of resources – and trying to keep lead times down.” Intentia already had an advanced production planner that supported TOC, but Dalziel says it was incomplete. “We’ve closed the gaps,” he says, “for full DBR [TOC drum buffer rope].” With that in place, he insists that lean and TOC go hand in hand. “Lean manufacturing makes value flow through the factory, and TOC takes it further by recognising critical bottlenecks,” he explains. “Businesses have to take waste out if they want to stay competitive… And when you have shared resources that different product lines and streams are going through, you need TOC to consider different product mixes in the round. “The TOC production planning solution is a low-risk tool that can be implemented in under three months with limited resources. It is an easy way for organisations to get major business performance improvements without replacing their backbone system.”