Lead time syndrome

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The lead time syndrome or lead time syndrome describes a sequence of effects that undesirably lengthen the lead times of orders in production systems and thus adversely affect the ability to plan deadlines . By triggering many orders in a short period of time, increasing stocks of material are created in the production area, since the orders cannot be processed at the same time due to capacity restrictions. According to Little's Law , the lead time is extended and the ability to plan the deadlines is also worsened.

causes

The reasons for this behavior are situations in which delivery delays to the customer are observed. The trigger for such delays can be internal or external to the system and can even arise from random fluctuations. As a result, orders are often triggered earlier than usual in order to ensure that deadlines are met. This floods production with orders that further reduce the performance of the production system. As a result, stocks of raw materials also increase in order to meet the demand for production. The situation is often described as a vicious circle for which various solutions are offered.

Possible solutions

Computer systems in the tradition of scientific management resulted in Manufacturing Resources Planning , in which the capacities were often only incompletely taken into account and which were therefore susceptible to the lead time syndrome. Additional systems, so-called Advanced Planning and Scheduling (APS) systems can improve the situation for predictable production units. Alternatively, optimization algorithms such as the Theory of Constraints according to Eliyahu M. Goldratt or just-in-time approaches such as Kanban , Conwip , load-oriented order release (BOA) and other possible approaches offer solutions to the problem. An optimal solution is currently not known.

Individual evidence

  1. ↑ a b Stefan Kiener, Nicolas Maier-Scheubeck, Robert Obermaier and Manfred Weiß (2012): Production Management: Basics of Production Planning and Control ; Walter de Gruyter; ISBN 3-486-24940-1 ; P. 273 ff.
  2. ↑ Lead time syndrome index card in the process design learning card index ; Retrieved September 19, 2016.
  3. ↑ JDC Little (1961): A Proof of the Queuing Formula L = λ W. In: Operations Research. 9, 383-387. ( http://www.jstor.org/pss/167570 ).
  4. ↑ a b Ulrich Weingarten (2013): Resource deployment planning in workshop production ; Springer Verlag; ISBN 978-3-662-12920-3 ; P. 18 ff.
  5. ↑ a b Index card throughput time syndrome in the learning card "Integrative Concepts"; Retrieved September 19, 2016.
  6. ↑ a b Jürgen Bloech, Ronald Bogaschewsky, Udo Buscher, Anke Daub, Uwe Götze, Folker Roland (2014): Introduction to Production ; Springer-Verlag, ISBN 978-3-642-31892-4 ; P. 262 ff.