Conventional shop floor control functionality of an ERP system, for the most part, is suitable for discrete manufacturing. However, during last two decades, interest surged for Just in Time manufacturing technique which is suitable for high volume repetitive manufacturing. New functionalities in the ERP system were developed to support repetitive manufacturing so as to maximize throughput, minimize waste and reduction of set up time.
Although majority of manufacturing is discrete, process industries, consisting of chemicals, food processing, paint, pharmaceutical, biotechnology etc., comprises an important segment of manufacturing. Functional requirements for both process and discrete industries for various financial and distribution modules are similar. However, functionality needed for production and operational control is widely different. Under discreet manufacturing distinct items are produced using BOM and routing whereas under process manufacturing, end product, produced out of continuous process, can not be distinguished from each other.
Repetitive manufacturing: Important element of repetitive manufacturing is where schedules, where production orders are consolidated into schedules. Another important consideration for generation of schedule is capacity of bottleneck work center. On completion of schedule run, completed units are moved to inventory and lot/serial number is assigned. Pull notes are used to transfer material between work centers.
A repetitive type of manufacturing environment has the following characteristics:
Mass production with speed and high throughput.
Item produced are generic in nature.
Item produced are not linked to a particular production order and are normally made to stock for distribution through warehouses and sales channels.
Supports rate based scheduling which includes setup and changeover time as well as maintenance scheduling.
Cluster of work centers are grouped into assembly lines.
Repetitive manufacturing procedure: A schedule consists of production orders with completion date that falls in the same period. The production orders under a schedule (with like delivery schedule) can be grouped by item where different routing and production facilities are used for the same item. Alternatively, production orders may be grouped based on production facility where different items, following different routing, are produced in the same production facility. On completion of a production schedule, status of all linked production orders is changed to complete and related financial, cost and variance transactions are generated.
Repetitive manufacturing history: A strong analytic capability is available with repetitive manufacturing, which effectively supports panning and control. Some of such reports are I) A production history provides current date, month to date and year to date results and calculation of average and maximum production results. II) A purchase schedule report shows scheduled receipts of materials on daily/hourly basis during the planning period III) A downtime analysis reports highlight of all cases of downtime IV) A production work list compares production plan to the capacity plan for rate based items.
Process Manufacturing: Under process manufacturing, final product along with by products and co products are produced from ingredients through continuous production process which is identifiable by batches. During the production process, the ingredient is gone through chemical changes such as mixing, blending, and encapsulating. The functionality needed for production module of process industry is distinguished by the following:
Instead of BOM and routing (as used in discrete manufacturing), functionalities such as recipe (process routing)and formula (process bill of materials) managing is needed.
Governance and compliance requirement is more stringent, due to various statutory necessities. Production is made in batches and batch traceability become critical in the event of a product recall. Therefore, extensive lot control functionality is needed. Ingredients often enter the system on a quarantine status and are released for processing only after extensive quality testing. This type of quarantine management is also a required functionality for pocess control software.
Another important functionality is the ability to adjust batch sizes depending upon available inventory of ingredients/ other materials.
Recipe Management: Recipe management is a key functionality related to batch processing in a process industry. This improves control of sequential batches. Another important feature is version control of which ensures that correct version is always used. Recipe management also helps in monitoring of expiry date, self life and potency for a batch.