|
|
|
News Services Consulting Customer Support Scheduling Technology Research Professional Place
|
(PROduction Scheduling Planning And Control) PROSPAC is a robust production control system designed especially for jobshops as well as make-to-order manufacturing companies in general. The many interesting features incorporated into this mature system are the result of an on-going continuous developmental effort that began in 1967. Almost any enterprise that is required by contract to produce a product or service according to a customer-negotiated delivery schedule is a likely beneficiary. The system is comprised of several components that together service the full range of production management demands:
PROSPAC derives its greatest user benefits from its scheduling capabilities. Its finite-capacity scheduling "engine" schedules all operations defined on the routings of all shop work orders which are released to a shop's floor, otherwise known as the shop's load.
Why is scheduling so important? When a shop is lightly loaded, say less than 40 percent, scheduling for purposes of making timely customer deliveries is a relatively undemanding task in most cases. But as a shop's load increases to 70 percent and beyond, it becomes exceedingly difficult to consistently make promised delivery schedules. Yet many shops have inadequate or even no production scheduling resources whatever. The order in which work is performed on the shop floor is most often managed by an experienced, clever foreman who is intimately familiar with almost all the parts being manufactured, and who knows what he can get out of his crew and the machines they operate. This is a part of the production management model that has proliferated, mostly unchanged, since World War II. In today's global economic environment, however, there is growing competition for American manufacturing companies. Customers are demanding ever-higher quality parts, ever-shorter leadtimes, unfailing delivery performance with ever-constant pressure on prices. Many manufacturing companies have derived significant benefits from tools such as MRP II, JIT, KANBAN, and other methods that essentially emphasize inventory management. But not a few disappointed jobshops and make-to-order manufacturers have struggled mightily to use some of these well-publicized methods only to come away frustrated, bewildered and rather cynical regarding computerized production control tools. This is mostly because these tools are really inventory management approaches which concentrate on the costs of raw materials and finished goods inventories, grieviously lacking robust production control methodology. These two kinds of inventory really don't pose much of a problem for most jobshops and make-to-order manufacturing companies because they have customer orders that specifically demand them, so that their carrying costs are easily managed with good purchasing delivery schedules for raw materials, and by consistently performing to promised customer delivery schedules for finished goods. On the other hand the cost of work-in-process inventories must be carefully managed. This is one of the reasons why it is so important to establish and pursue product leadtime reduction objectives in tandem with the on-time delivery objective. Meeting these two complimentary objectives simultaneously is obviously a win-win situation for both your customers and you. PROSPAC is the tool that brings this into the sphere of achievability.
Now, the truth about MRP II promises! The primary management focus of jobshops and other make-to-order manufacturing companies must therefore always be capacity management, never inventory management! It is not that wise inventory controls should be discarded, quite the contrary. But they are tertiary at best because they often do not support, and sometimes even conflict with, manufacturing management objectives that produce satisfied customers. Except for work-in-process inventory, they should never be used to fashion production control policy. Make-to-order enterprises typically do not build-to-stock. They are really selling their capacity. Astute management of that capacity is therefore paramount for business success. This is why the rough-cut capacity planning feature offered by classical MRP II approaches is grossly insufficient and unsatisfactory to the last degree for jobshops and make-to-order manufacturers. But capacity management as well as work-in-process inventory management can only be effective when efficacious production scheduling is used to manage what-happens-when on a shop floor. PROSPAC is a tool that provides coordinated capacity management to the greatest possible level of detail. With its scheduling "engine", it determines the beginning time and ending time for every operation of every shop work order on every finite-capacity machine and manpower resource, accurate to the nearest 6 minutes, for as far out into the future as work orders are declared! This could be for thousands or even hundreds of thousands of operations! Furthermore it determines these times so that all shop work orders are delivered to the customer community as promised, insofar as that is possible. The more heavily a shop is loaded, the more critical proper machine sequences of operations from competing work orders are relative to when each such competing shop work order will eventually complete. Each operation of a shop work order has a schedule "window" on the required machine within which it must be scheduled in order for the shop work order itself to complete on time. Operations from other shop work orders, demanding the same machine, generally have overlapping "windows" of their own and thus compete for available capacity in this same window. The trick is to find a sequence of operations so that each operation's resulting schedule fits somewhere within its respective window. Failure to find such a sequence generally means that one or more shop work orders will not finish on time. PROSPAC not only finds these optimum machine operation sequences, but also coordinates them among all machines on the shop floor! Once we have optimized machine operation sequences, particularly on "bottleneck" machines, it is almost always the case that a shop will experience increased machine utilization on those machines performing operations following the "bottleneck" machines. This in turn leads to increased production throughput. As a result it is not uncommon for a shop to produce 10 percent to 40 percent more work in the same time frame with the same shop resources, when PROSPAC's schedules are used to direct work on the shop floor, relative to manual methods. It is almost as if a shop experiences a 10 to 40 percent gain in capacity, without having any of the associated costs. What it really amounts to, of course, is that PROSPAC is now able to access capacity that was formerly idle, due to nothing more than the lack of a good schedule. Because of these much higher machine utilizations, production management can use PROSPAC to successfully manage shop loads beyond 70 percent into the 90-percentile range. Successful management simply means negotiating achievable customer delivery schedules in the first place, and then performing to those schedules. It is a well-known fact that most customers remain customers so long as they can depend on a shop to consistently perform to its delivery schedule promises. In as much as quality is not sacrificed, they are often willing to negotiate a somewhat longer leadtime and sometimes even a somewhat higher price if they know they can get their parts as promised. If you intend to manage a high-percentage-load (70%+) shop, PROSPAC is the tool you need to consistently deliver results from your shop floor to your customers. From order entry to order delivery, PROSPAC is there to insure that promised customer delivery dates are kept. At the same time it allows you to confidently accept a continuous stream of orders, day after day, selling as much of your available capacity as possible. If you can't sell all of your available capacity, PROSPAC shows you how to reduce capacity, preserve and protect key skilled-labor resources, experience high resource utilizations, and still make customer deliveries on time. On the other hand, when you have more customer orders than you can deliver on time, PROSPAC shows you how to selectively increase capacity by offloading, working overtime, splitting work orders, subcontracting, renegotiating some customer delivery quantities, increasing crew size, and adding machines. PROSPAC may be the finest production control package there is for jobshops and make-to-order manufacturing enterprises. It provides an incomparable level of production management support, as well as the capabilities you need to offer unmatched levels of service to your customers. Want an introduction to PROSPAC's most compelling features? Find out why salesmen, manufacturing managers, foremen and even floor leads like this system.
|
|
Send mail to webmaster@heuristima.com
with questions or comments about this web site.
|
