تجزیه و تحلیل از صنعت خدمات و تولید

Production flow analysis (PFA) is a well-established methodology used for transforming traditional functional layout into product-oriented layout. The method uses part routings to find natural clusters of workstations forming production cells able to complete parts and components swiftly with simplified material flow. Once implemented, the scheduling system is based on period batch control aiming to establish fixed planning, production and delivery cycles for the whole production unit. PFA is traditionally applied to job-shops with functional layouts, and after reorganization within groups lead times reduce, quality improves and motivation among personnel improves. Several papers have documented this, yet no research has studied its application to service operations management. This paper aims to show that PFA can well be applied not only to job-shop and assembly operations, but also to back-office and service processes with real cases. The cases clearly show that PFA reduces non-value adding operations, introduces flow by evening out bottlenecks and diminishes process variability, all of which contribute to efficient operations management.

The late Professor John L. Burbidge (Grubbström, 1996) used to ask his students why Adam Smith ignored the challenges related to efficient operations management in his otherwise all-encompassing book the “Wealth of Nations.” Even in the famous pin-factory example, Smith fails to refer to the problems of layout design, throughput and operations management in general and only treats the benefits stemming from the division of labor. By keeping his audience in suspense Professor Burbidge eventually revealed that the factories at the time of Smith were nothing, but the size of a group, so the problems related to the management of operations were not of immediate importance to the father of capitalism. In the middle of the 17th century, manufacturing took place in small shops of artisans, where everything was based on visual control and simple material flow, with little need for complex planning and control ( Jaikumar, 2005). Since the days of Smith, manufacturing units have grown in complexity and scale, most of them have grown into functional layouts with non-trivial material flows setting the challenge for Professor Burbidge to develop his approach aimed at turning them back to product-driven layouts as in days of old. Production flow analysis (PFA) was developed and detailed by its inventor during late 70s and early 80s. The method is well documented (Burbidge, 1989) providing practitioners and consultants with a step-by-step approach to apply the method in environments with multiple operations and machines. In short, PFA is a well-established methodology used for transforming a traditional functional layout into a product-oriented layout (Fig. 1). The method uses part routings to find natural clusters of workstations forming production cells able to complete parts and components swiftly with simple material flow, and simpler manufacturing systems have been seen to be more efficient than more complex ones (Sarkis, 1997). The same approach can be used to analyze production units as well as the line layouts within a cell. Once implemented, the scheduling system is based on period batch control aiming to establish fixed planning, production and delivery cycles for the whole production unit. In addition to PFA, the same analogy can be applied to other levels of the business, namely the corporate level to analyze flows between companies (company flow analysis) and departments (factory flow analysis).

Production Flow Analysis is a mature, well-documented and practically proven method to simplify complex material flow systems, especially to transform traditional functional and process-oriented layouts into product-oriented ones. Despite its established track record, it is not that widely used. Therefore, one of the unwritten aims of this article is to refresh the legacy of PFA and to invite more research, applications and cases to further develop it. These future studies will hopefully corroborate that PFA can be applied to contexts other than job-shop and assembly environments. The present cases clearly show that PFA produces results that comply well with the current body-of-knowledge in operations management. It is a powerful method to streamline material flows in order to obtain the benefits that can be predicted by the established operations management theories. Shorter lead times reduce process variation, smoothen the flow, improve inventory turns and improve quality. Once implemented, PFA enables fixed operational cycles to be introduced to level the load and release capacity, which results in simple production scheduling, thus reducing the overhead in central administrations. Fixed operational cycles have traditionally been implemented in job-shops and assembly industries, yet they can also be used in other industries to improve planning accuracy. For the sake of objectivity, it is debatable whether the results obtained in the cases could have been achieved without PFA. The answer must be positive: Yes, the results could have been achieved without PFA through the use of hands-on experience on cellular production and the industries concerned. Fundamentally, common sense is needed when transforming a functional layout into a product-oriented one, and PFA is a kind of standard operating procedure that systematically guides the company through the change process. The fact-based stance of PFA serves as a means of communicating and convincing all actors involved to work towards the simplified material flow system. Although the number of cases in this study is small, it still provides the operations management research community with the inductive support that all value-creating processes, where work flows through different tasks, can be streamlined with the PFA methodology. Yet, in strict flow and process industries, the use of PFA is naturally limited. Professor Burbidge himself was well aware of this as he used to joke that the method was not that well applicable to his favorite industries, such as breweries and distilleries.