JJ MRP system manages the manufacturing of over 7, 000 finished good part numbers and over 35,000 component parts. Any of these finished parts can be sold to over 1,000 customers. Running full MRP through scheduling at JJ results in a very nervous system. The reason is not that customers are continually changing requirements. Rather, in several departments (assembly, molding, machining, stamping & polishing) there are as many as 150 different workstations or machines. And at any given time, nearly 10% will be down for maintenance. So, moving jobs from the originally planned work center to an alternative work center results in continuous MRP changes and regenerations. This continual regeneration of MRP slows down our whole system. Sometimes even making it difficult for sales and customer service to access information quickly when customers are on the phone. Increasing computer power is not a realistic option and offers no real assurance of solving the speed problem.
So we have two options. We can live with the nervousness of the MRP system, continually looking for small ways to get small improvements. Or, we can remove workstation routing from the MRP system and allow the department supervisors to do the job scheduling at the work center level manually.
Which option do you prefer and why?