Intended learning outcomes: Explain how the lean /JIT concept reduces queue time. Describe how the lean /JIT concept allows for simpler control techniques.
The setup time reduction in Section 6.2.1 can achieve sufficiently short setup times even without cyclic planning. In this case, it is no longer necessary to reduce setup times by forming groups of orders for which a queue and thus some buffer inventory is required. Because priority rules for the waiting orders before the workstations are less necessary or fall away altogether, control in job shops becomes less complex.
Maintaining overcapacity, or — in case of expensive production equipment — of flexible capacity was discussed in the first part of Section 6.2.3 as part of the lean /JIT concept. This measure has the following positive consequences:
- It reduces queue time. This is crucial if the focus is on delivery reliability, given that queue time is one of the least predictable factors in job shop production. If queue time varies little or is very short, this improves planning, particularly for several production structure levels. Decreased size of production areas, thanks to smaller inventory in queues to the workstations, represents a further advantage.
- It allows for simpler control techniques, such as the Kanban technique. But any technique at all of capacity planning will function better. In addition, when an IT-supported control technique (e.g., with ERP or SCM software) is introduced, there will quickly be external costs of at least $100,000 and total costs of at least three times that amount. Therefore, increasing capacity can prove to be a viable alternative, particularly when it can be implemented more rapidly than a computer control technique. In a medium-sized Swiss electronics manufacturing firm, for example, the purchase of two additional coiling machines resolved a bottleneck in capacity. In this way, the firm was not only able to avoid investing in an expensive control technique, but also chose a measure that could be put into effect immediately.
Quiz: Find the correct answers to the following question - not yet available
[kml_flashembed movie="https://opess.ethz.ch/wp-content/uploads/2016/09/Q_626.swf" height="75%" width="100%" /]Course section 6.2: Subsections and their intended learning outcomes
6.2 The Lean Concept / Just-in-Time Concept
Intended learning outcomes: Explain lead time reduction through setup time reduction and batch size reduction as well as further concepts. Describe line balancing through harmonizing the content of work. Disclose Just-in-Time Logistics. Present generally valid advantages of the lean / Just-in-Time concept for materials management and for capacity management.
6.2.1 Setup-Friendly Production Facilities — Lead Time Reduction through Setup Time Reduction and Batch Size Reduction
Intended learning outcomes: Identify the simplest formula for operation time. Produce an overview on setup-friendly production facilities.
6.2.1b Cyclic Planning and “Heijunka” — Lead Time Reduction through Setup Time Reduction and Batch Size Reduction
Intended learning outcomes: Present in detail cyclic production planning and leveling of the production (“heijunka”).
6.2.1c Reduction of Variants, Modular Product Concept, Single-Minute Exchange of Dies (SMED) — Lead Time Reduction through Setup Time Reduction and Batch Size Reduction
Intended learning outcomes: Describe harmonizing the product range through reduction of variants and a modular product concept. Explain single-minute exchange of dies (SMED).
6.2.2 Production Segmentation, or Manufacturing Segmentation — Lead Time Reduction Through Adaptation of the Production Infrastructure
Intended learning outcomes: Produce an overview on production or manufacturing segmentation.
6.2.2b Cellular Manufacturing and One-Piece Flow — Lead Time Reduction Through Adaptation of the Production Infrastructure
Intended learning outcomes: Explain cellular manufacturing, one-piece flow, and the formula for lead-time calculation with cellular manufacturing.
6.2.3 Standardizing the Production Infrastructure, Flexible Capacities, Structuring Assembly Processes, Complete Processing, Point-of-Use Inventory, Point-of-Use Delivery — Further Concepts of Lead Time Reduction
Intended learning outcomes: Disclose the effect of standardizing the production infrastructure and of flexible capacity. Describe structuring assembly processes and complete processing. Identify point-of-use inventory and point-of-use delivery.
6.2.4 Line Balancing — Harmonizing the Content of Work
Intended learning outcomes: Identify how tasks of the same duration at each production structure level result in a rhythmic flow of goods. Explain why the various operations at a workstation (for all the products) as well as the various operations for a single product should be of the same approximate duration.
6.2.4b Line Balancing — Changing Lead Time of Operations
Intended learning outcomes: Produce an overview on measures for changing lead time of operations.
6.2.5 Just-in-Time Logistics: Quality Circles, TQM, Genchi Genbutsu, Kaizen, Poka-Yokero, Andon, 5S, and Others
Intended learning outcomes: Produce an overview on measures for motivation, qualification, and empowerment of employees as well as employee involvement (EI and quality circles. Describe concepts such as genchi genbutsu, kaizen, poka-yokero, Andon, 5S.
6.2.6 Generally Valid Advantages of the Lean / Just-in-Time Concept for Materials Management
Intended learning outcomes: Describe the effect of forecast errors through the combining of requirements in batches across many production structure levels. Explain the effect of longer and shorter lead time on the (customer) order penetration point.
6.2.7 Generally Valid Advantages of the Lean / Just-in-Time Concept for Capacity Management
Intended learning outcomes: Explain how the lean /JIT concept reduces queue time. Describe how the lean /JIT concept allows for simpler control techniques.
