Topic outline

  • General

    • Drum Buffer Rope & Theory of Constraints

      Companies are always interested in maximizing profit. Maximum profit is typically limited by bottlenecks. But companies can use the Drum Buffer Rope (DBR) concept to use those bottlenecks efficiently. DBR is a concept of Lean management and it is built on the theory of constrains (TOC).

      The TOC analyses the value chain of a company and focus on optimization of bottlenecks. DBR implies that bottlenecks give the pace or “beat” of the production. Then, all production stages are synchronized by the beat of the drum keeping the pace set by the bottleneck. The length of the rope is the buffer that absorbs the changes in capacity along production before and after of the bottleneck. The goal is to increase production throughput over time by use the use of constrains efficiently.

       

       


      • Planning and control in HVLV

        Methodological History

        This is the introductory video that will give a short overview of important methodological developments in the planning and control at HVLV Companies.  We distinguish six important developments:

        1. Period Batch Control: fixed lead times = simplified cell coordination
        2. Material Requirements Planning: Software copes with complexity and supports timely order release
        3. KANBAN / Just in Time: activity trigger is customer demand
        4. POLCA: standardize the flow of goods
        5. The CONWIP-FIFO-TAKT system: limits/sets decision space for release and dispatching
        6. Digital Twin control: smart decisions in a complex flow system

         

         

        Period Batch Control 

        This video will explain the concept of Period Batch Control step by step, the first Just-in-Time system.  We will draw major lessons that can be used in modern production planning and control.

         

         

        Material Requirements Planning

        This video will give a short overview of Material Requirements and Resource Planning (MRP).  We will present and discuss strong and weak points of the system.

        MRP creates material plans and production schedules based on the lead times of the supply chain.  MRP makes use of software to create linkages between the demand of final products and the jobs to be done at the work floor. Also, MRP makes use of an aggregate production plan which concerns the ambition of the company with respect to the demand for each of the product groups. 

          

          

        KANBAN / Just in Time

        Just in time (JIT) is a Japanese management philosophy which has been applied in practice since the early 1970s in many Japanese manufacturing organizations. It was first developed and perfected within the Toyota manufacturing plants by Taiichi Ohno as a means of meeting consumer demands with minimal delays. This short video explains how JIT and Kanban work briefly.

         

         

        POLCA: An overview

        This video is a short explanation about POLCA. POLCA is a planning and control system which was designed by Rajan Suri, the founder of the Quick Response Manufacturing.  It is focused on realizing short throughput times.  The POLCA planning and control system assumes the presence of dependent cells that deliver items to other cells. Each manufacturing order requires processing within a number of cells.  

         

         

        CONWIP-FIFO-TAKT

        This video explains the three principles of The CONWIP/FIFO/TAKT planning and control system. This system was developed at the company Eaton Holec in the Netherlands.  It is easy to implement and does not ask a lot of data.

        First, there is the CONWIP principle.  The number of jobs in the system is constant.  Little’s law helps us to understand that in this case, if demand in constant, also the average throughput time is constant. 

        Another principle is FIFO (first in, first out).  The carts leave the system in the same sequence as they entered the system.  

        The principle is ‘TAKT’: the workers know how much time they have for their routing.  This depends on the demand of the customer, or the next cell.  The TAKT-principle is important for realizing sufficient output.  

         

         

        • Additional Material