S88 and Material: What is Going on Beyond the Process Cell?

Overview:

The S88.01 Batch Control standard focused almost exclusively on the process cell and the activities and functions associated with it that convert raw material inputs into one or more output material products. This focus was intentional and was necessary for the completion of the standard within a reasonable time. However, for that reason, it only vaguely defined how material gets to and from the process cell. This leaves a disconnect of some magnitude between batch control, which is activity centric, and business processes that are largely material centric. This paper presents a view of material flow in a manufacturing site described in S88 compatible terms, recognizing that physical control of material is necessary, but that it must ultimately interact with and fulfill business requirements. The fundamental assertion is that conversion of material within a process cell is only one of five functions or activities necessary to manage and control material within a manufacturing site. It presumes that, in addition to the conversion of material from one form to another, material must be received, moved, stored and shipped. The concept of a storage cell is introduced, as is the concept of common resources that can be shared between process cells and storage cells for the physical movement of materials. Also treated, in the context of real-time control, are the functions of material receipt, material shipment and the business oriented scheduling required to organize activities across a site.