Just-In-Time (JIT) Manufacturing Systems
Speed to market and costs of production are critical factors in manufacturing which can make or break an organization. Just in time (JIT) manufacturing is a one workflow methodology that aims at reducing process flow times within manufacturing systems and response times from suppliers, and to customers.
It is a manufacturing model where items are exactly created to meet demand, not in surplus or with the hope of meeting a need. JIT manufacturing has the objective of avoiding the waste associated with overproduction, waiting and excess inventory. JIT manufacturing enables organizations control variations in their processes, helping to increase productivity while lowering costs.
History of Just-in-Time Manufacturing
JIT started from Japan with the Japanese manufacturers adopting it in their manufacturing operations. While the exact that JIT started is unknown, it is certain that they were triggered by the economic climate of the post-World War II era. After the war, Japan suffered shortages in the cash to finance big-batch, large inventory production methods used by other developed countries.
To meet with the challenge, they needed to go ‘’lean’’. These they did by building smaller factories, which focused on turning small amounts of raw materials into small amounts of physical products in very short period of time, thereby allowing them to reduce financial risk, while slowing generating sustainable levels of working capital.
This was the start of the adoption of just in time manufacturing system, popularized in Western media as the Toyota Production System.
The JIT Elements
Implementing a JIT manufacturing system requires some levels of discipline, structure, and explicit processes. In addition to strictly controlling inventory level, the following methods are included in a JIT system:
- Housekeeping: physical organization and discipline through 5S implementation
- Defects Elimination: Through elimination of process and product defects
- Improved Changeovers and Setup Time: Setup reduction and flexible changeover approaches
- Manufacturing Lot: Production of small lot sizes
- Uniform plant load: Levelling as a control mechanism
- Balanced flow: Actively managing flow by limiting batch sizes
- Skill diversification: Multi-functional workers
- Control by visibility: Using visual tools to improve communication
- Process Design: Designing for process
- Materials movement: Streamlining the movement of materials
- Cellular manufacturing
- Kanban
Benefits of JIT Manufacturing
When done well, adopting a Just-in-Time manufacturing system can have a drastic positive impact on your company’s productivity and operating costs. The following are some of the quantitative benefits experienced by many manufacturing firms that have been able to successfully adopt JIT manufacturing worldwide:
- Reduction in inventory
- Reduction in labor costs
- Reduction in space needed to operate
- Reduction in WIP (work in process)
- Increase in production
- Improvements in product quality (lower rates of defects)
- Reduction of throughput time
- Reduction of standard hours
- Increase in number of shipments
Potential Risks
While JIT manufacturing practices enables reduced cycle times, faster times to market, and reduced operating costs, it’s important to find suppliers that are close by, or that can supply materials quickly with limited advance notice. When this is not the case, smaller manufacturing firms who might order smaller quantities of materials might not be able to get the full benefits of JIT manufacturing system.
About the Author
Adebayo is a thought leader in continuous process improvement and manufacturing excellence. He is a Certified Six Sigma Master Black Belt (CSSMBB), Digital Manufacturing Professional and ISO Management Systems Lead Auditor (ISO 9001, 45001 & ISO 22000) with strong experience leading various continuous improvement initiative in top manufacturing organizations.
You can reach him here.
