# 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”).

Continuation from previous subsection (6.2.1).

2. Cyclic planning:

Cyclic planning attempts to sequence the products to be manufactured by a machine in such a way as to keep total setup time at a minimum.[note 607].

Cyclic planning is an example of sequencing, the planning of optimum sequences. Cyclic planning yields a basic cycle, as Figure 6.2.1.2 shows.

Fig. 6.2.1.2        Cyclic production planning.

In a cyclic manner, batches of parts A, B, E, D, and C are manufactured. It is simple to introduce variations in order quantities; additional batches are planned for a part at the same point that has been planned for that part in the basic cycle. Varying the quantity according to current requirements could also result in a cycle of A, E, E, D, and again A.

Exercise: Try to find a sequence of parts A, B, C and D with a minimum setup time. For creating a sequence, drag parts to the empty circles. The result is called a basic cycle.

Reducing the setup time allows for reducing the lot size. Therefore, instead of producing a big lot of each product (e.g., 1000 A, 4000 E), several cycles of smaller lots can be produced (e.g., 4 * 250 A, 4 * 1000 E). This leads to the principle of leveling of the production.

Leveling of the production (Japanese “heijunka”) is an approach to level highly discontinu­ous production orders throughout the supply chain to match the planned rate of more continuous customer demand. It is an important tool for reducing “mura.”

“Ideally,” a product should be produced on the day it will be shipped.

Continuation in next subsection (6.2.1c).

## 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.