The Benefits of Structured, Repetitive Production Scheduling
The shop floor is all too often the victim of schedules that are poorly sequenced, causing unnecessary changeovers which result in impaired line efficiency. These schedules create unnecessary chaos which drain the energy and performance of shop floor teams. This is not how it should be! Turn things around with structured, repetitive production scheduling that reduces changeovers, increases throughput, and properly balances inventory levels.
Scheduling Chaos Happens all too Often
Many manufacturing plants base their daily production schedules on planned orders that come from the corporate ERP system based on MRP logic. The primary focus of the logic behind these systems is to meet shipping due dates, but this focus creates a string of orders which appear to be random. Furthermore, these orders fail to take advantage of opportunities to increase useful capacity and throughput by optimizing production sequences and minimizing changeovers. A production scheduling methodology called Product Wheels allows schedulers to easily exploit those opportunities.
Product Wheels Breathe New Life into Production Schedules
You may be thinking this is a bold claim, and have doubts on whether Product Wheels would have a big impact on your production schedule. You may be wondering…
“Why change things? Our scheduling is going just fine”. In my experience of working with dozens of companies, nearly all production schedules that do not incorporate a scheduling methodology like Product Wheels have inefficiencies that can be improved upon. Sometimes it isn’t until these inefficiencies are uncovered that you realize the savings in time and resources that you’ve been missing out on.
“This won’t work – we need to be able to quickly change our schedule due to rush orders.” It’s impossible to eliminate the unexpected, which is why Product Wheels are designed to determine where to best fit rush orders without completely turning the schedule upside down. On top of that, Product Wheels incorporate regular maintenance into the schedule, significantly reducing the amount of unexpected equipment failures you’d need to deal with.
What Exactly Is A Product Wheel?
A Product Wheel is a structured, regularly repeating sequence of the products made on a production line or major piece of processing equipment. The overall cycle time is fixed, and is optimized to give the best economic balance between the cost of changeovers and the cost of carrying inventory, consistent with other requirements like shelf life and minimum lot sizes. High volume products are made on every cycle, and always at the same position in the Product Wheel rotation. Lower volume products might be made every second or every fourth cycle, again based on the best economic balance. Each cycle is sequenced to give the shortest or least costly path through all products made on that cycle. Make-to-order products are positioned on the Wheel so if there are orders, it has been predetermined where they best fit in the sequence. Optimizing the lot size and production frequency of lower volume products tends to increase throughput, as does the sequencing of products to simplify changeovers.
Product Wheels capitalize on what are called “the economies of repeatability”. And Product Wheels achieve the lean goal of Heijunkja, production levelling.
Significant, Lasting Benefits
Time and time again I’ve seen Product Wheels transform unpredictable schedules with excessive changeovers and overtime into predictable, stable schedules that meet the needs of the customers while creating significant cost savings opportunities for the company.
Working with Nature’s Bounty, a global nutraceutical manufacturer struggling with constant changes to production schedules and frequent, inefficient changeovers, Product Wheel scheduling led to a throughput increase of 35%. As a result, they were able to shut down several packaging lines, saving $1.5 million annually in operating costs. Given the significant impact made by Product Wheel scheduling, the company was eager to continue working with Zinata to implement Wheels at all of their other packaging plants and one gelcap manufacturing plant.
Product Wheels Provide:
– Up to 30% more manufacturing throughput
– Predictable, standardized production cycles
– Right-sized inventories
– Improved customer delivery performance
– Enhanced supply chain stability
In addition to the increase in throughput that the Product Wheel patterns bring, customer delivery performance often improves; the predictable, standardized production cycles allow inventories to be right-sized to meet customer needs.
The stability, predictability, and repeatability that Product Wheels bring tends to set a rhythm or cadence for the entire supply chain, which enhances supply chain stability and predictability.
Unlock Manufacturing Capacity
Product Wheels make a scheduler’s life much easier by establishing standard patterns for all the routine scheduling decisions, and can significantly impact the bottom line for companies.
Explore how Product Wheels could make a difference at your company by completing a Product Wheel Assessment created by industry experts at Zinata Inc.
About the Author:
Peter L. King, Principal Consultant Planning and Scheduling, CSCP, is a globally acknowledged expert on Product Wheel scheduling, international advisor to leading manufacturing companies, theoretician, and practitioner who has notched up tens of millions of dollars in annual improvements in chemical, food, and nutraceutical plants. He spent 42 years at DuPont where he transformed manufacturing operations and global supply chains through Value Stream Mapping, Supply Chain Mapping, inventory optimization, and other Lean tools. King is the author of several books including The Product Wheel Handbook.