Weaving enterprise optimization from the plant floor to glass house and through the supply chain requires sorting through difficulties, weighing options, and eliminating confusion. Related solutions and user and vendor recommendations are included in AMR Research's (AMR, Boston, Mass.) Oct. '99 Report On Manufacturing titled "Variability: The Cure is Out There," written by AMR's research...
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Weaving enterprise optimization from the plant floor to glass house and through the supply chain requires sorting through difficulties, weighing options, and eliminating confusion. Related solutions and user and vendor recommendations are included in AMR Research’s (AMR, Boston, Mass.) Oct. ’99 Report On Manufacturing titled "Variability: The Cure is Out There," written by AMR’s research director of manufacturing strategies, Roddy Martin.
The AMR Report correctly identifies that most Enterprise Resource Planning (ERP) solutions grew out of transaction-oriented discrete manufacturing applications, where material lists and routings are fixed for a product and yield and component costs have fixed relationships. Discrete manufacturing does not permit assembly of 1.5 vehicles from components assembled for one vehicle, but in process manufacturing it is possible to obtain different yields from the same quantity of raw materials and resource efforts.
Sources of process yield variability include raw material potency characteristics, inefficient equipment, intermediate product shelf life, and even seasonal weather conditions. Recognition of a need to include variability tracking and analysis as an integral part of an enterprise integration solution is the emphasis of the AMR report.
When a list of what’s required to meet today’s customer requirements is created, quality is always near the top. Yet capturing, analyzing, and determining root causes of variability and cross-functional implications are beyond the scope of today’s ERP solutions. What’s available is an ERP solution that helps administer, forecast, plan, schedule, and reschedule, but doesn’t help determine the root causes that initiated the need to reschedule and more importantly how to permanently eliminate those causes.
Mr. Martin says, "Total Quality Management (TQM) and Total Production Maintenance (TPM) initiatives engrained on most plant floors are not yet a part of the overall ERP solution space. ERP and Manufacturing Execution System (MES) vendors have generally remained at arm length from one another with ERP vendors downplaying the importance of MES applications. In some cases ERP vendors claim ERP solutions deliver the needed functionality, but users increasingly find this not always the case."
AMR’s report cites an example where a beverage manufacturer implemented a popular ERP application but discovered the time to obtain variation reports took substantially longer than in pre-ERP days. AMR’s report also explains how a brewing company has successfully provided short cycle production feedback to a discrete-oriented ERP solution to ensure responsiveness to production variabilities.
Renewed interest in MES
Dennis Brandl, enterprise initiative director with Sequencia Corp. (Scottsdale, Ariz.) and member of ISA’s SP95 Enterprise/Control Integration standards committee says, "Process manufacturing companies are rediscovering that MES functionality must reside at the plant level but above the control and automation system. Traditional MES functions include production:
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Schedule modifications;
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Costs optimization;
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Asset and resource availability information;
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Material usage information; and
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Quality and process control statistics.
SP95 committee activities have advanced from what information to communicate to/from the control domain to how information will be communicated. Exchange protocols being considered by the committee include SQL (Structured Query Language), XML (eXtensible Markup Language), and IDL (Interactive Data Language) object definitions."
It is adoption and use of standards and de facto standards, like XML, Microsoft’s BizTalk, SQL, SP95, OPC (OLE for process control), Microsoft SQL Server, DCOM (Distributed Communication Object Module), Java, ActiveX, and Visual Basic, that permit avoiding a repeat of built-from-scratch point solution shortcomings (see CE , Nov. ’99, p. 25). Today’s solutions start with a popular database, use a familiar graphical user interface, include pre-tested object modules, and follow structured development rules. The result is Built-For-Purpose (BFP) solutions designed to identify and remove variability yet easily integrate with other business applications.
For example, Intellution (Norwood, Mass.) offers VisiconX , a set of ActiveX controls that enable users to point and click to develop and execute unique SQL queries against disparate relational database and use the collected data to populate business reports, all without understanding SQL.
Bradley Ward Systems (Atlanta, Ga.) is focused on BFP solutions designed to meet specific plant-floor operational needs for food processing. Included in Bradley Ward’s Success suite is Hazard Analysis Critical Control Point planning and execution modules designed to meet USDA-FSIS (U.S. Drug Administration-Food Safety Inspection Service) regulations.
Hilco Technologies (East City, Mo.) Real-time Production Management (rtPM) , and Sequencia’s Open Batch, Procedure Manager ,and Production Manager are all BFP solutions for batch processes designed around the ANSI/ISA S88 batch standard models. Hilco’s rtPM provides MES functionality including material receiving and tracking, recipe scheduling and execution, and quality assurance modules. Sequencia’s Production Manager provides synchronization of plant floor and business systems data (i.e., SAP R/3 software) without programming and is built around Microsoft’s Distributed Network Architecture for Manufacturing.
ABB’s (Wickliffe, O.) Advant Enterprise Historian and Honeywell’s (Phoenix. Ariz.) Business Hiway are BFP solutions designed to integrate process industry operating domains with the PP-PI (Production Planning for Process Industries), PM (Plant Maintenance), and other application modules of SAP’s R/3 inter-enterprise business solutions.
Foxboro’s (Foxboro, Mass.) enterprise integration comes in the form of I/A Series Information Suite designed to integrate software applications and components from Foxboro, Simulation Sciences, and Wonderware, with leading ERP systems.
Improving things like raw material consistency and better use of BFP applications will improve planning and scheduling accuracy, but to become really good, to achieve "world class" capability, requires integrating process equipment health and status into the planning and scheduling equation.
Reduce variability, improve supply chain
Supply-chain management is all about reducing inventory and costs, but when yield variability in process manufacturing is not well managed, the solution is to maintain a "cushion" inventory of finished product—the most costly of solutions.
Jack Welch, ceo of General Electric (GE, Fairfield, Conn.), says, "An organization’s ability to learn, and translate that learning into action rapidly, is the ultimate competitive advantage."
At companies like Allied Signal Inc. (Morristown, N.J.), Motorola Inc. (Schaumburg, Ill.), and GE that statement is put into practice daily with analysis software from companies like SAS (Cary, N.C.). Such software aims to gain competitive advantage for its users by removing variability (see CE , Jan. ’99, p. 62, and Mar. ’99, p. 87).
When first-, second-, and third-tier supply chain vendors are added to the variability complexion, many manufacturers find it necessary to educate and support supplier efforts to remove incoming variability in order to eliminate outbound cushion inventory. Thus the overwhelming need for the enterprise information network is to be able to capture, analyze, and identify root causes of plant-floor variability in real-time.
Key to determining root cause is the ability to measure critical parameters and events, and it’s not always obvious things that create variability. For example, one company’s continuous improvement team optimized a process only to find a few days later that variability had returned. Using MDT Software’s (Alpharetta, Ga.) MASS AutoSave , root-cause analysisrevealed unauthorized and undocumented programmable logic controller software changes occurred during maintenance activities.
Determining root causes often require detective-like persistence, but tools and training such as those available from System Improvements Inc. (Knoxville, Tenn.) improve efficiency and effectiveness by prompting investigators through a consistent set of questions and categories. Responses are recorded in a searchable relational database to aid in identifying recurrences or similar root-cause events. When used proactively, root-cause analysis can identify potential production interruptions caused by equipment failures as well as reveal undiscovered production improvement opportunities (see CE , Dec. ’99, p. 25, "Managing risk improves production").
Equipment health can be the key
It is mystifying that just before a two-week scheduled maintenance shutdown, many process plants are run their "hardest" in an effort to meet customer requirements and build inventory cushion. It is possible to conclude that either the equipment isn’t really in bad enough condition to justify a maintenance shutdown, or heightened focus on reducing processing variability is indicating the processes real yield capability. Regardless, equipment health, status, and capability are key elements in achieving advanced planning and scheduling success.
Knowing the ongoing health of equipment requires establishment of a Reliability Centric Maintenance (RCM) organization (see CE , Jul. ’99, p. 46). Being able to use equipment health, status, and capability in planning and scheduling scenarios requires another form of BFP in the form of Enterprise Asset Management (EAM) or Computerized Maintenance Management System (CMMS) software from companies like Indus International (San Francisco, Calif.), PSDI (Bedford, Mass), and Mincom (Norcross, Ga.). When RCM is working at it’s best, and EAM/CMMS applications are integrated, supply-chain optimization can be further extended to include equipment spare parts inventory and contract maintenance services.
Identifying and attacking sources of variability to achieve world-class enterprise integration is not an overnight accomplishment, and likely not available as a single-source solution.
Help identifying, evaluating, and choosing software that’s right for you is available from companies like Expert Buying Systems (Las Vegas, Nev.) with its ChooseSmart product and services.
If all this is not enough complexity there is yet another piece of the integration puzzle. The enabling tool for gathering and sharing data to optimize every asset is an enterprise information network, a sort of digital nervous system .
Networking infrastructure
Since it is impossible to foresee enterprise information requirements several years in advance, a key requirement is for the digital nervous system to be "future proof" (see CE , Jun. ’99, p. 46).
When considering a digital nervous system networking infrastructure, three main components must be evaluated:
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Physical;
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Transport mechanism; and
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Application level.
The physical medium provides means to move data among managing devices. Widely known and widely available is Ethernet cabling. This ubiquitous collection of twisted-pairs of wire can be found in virtually any business today. The magnitude of Ethernet-related connectivity devices dwarfs any other physical networking medium today. Furthermore, the Ethernet knowledge base within most organizations far surpasses that of any proprietary industrial network.
How data are transported on the wire, or wirelessly, is the second component to evaluate. This really doesn’t have much to do with the data itself, but is more about how data move from one device to another over a selected medium. Clearly, Transport Control Protocol over Internet Protocol (TCP/IP) is the undisputed global leader. The beauty of TCP/IP is it’s ability to bind to many types of physical media, from wire to wireless, LAN to WAN, and on the other end, to encapsulate virtually any type of data. TCP/IP then becomes the real enterprise integration enabler. Because it can adapt to the physical and application layer in virtually any way, its use is nearly limitless. This leaves the application layer, arguably the most contentious among the industrial automation community, to evaluate.
Most Information Technology (IT) organizations rely on Ethernet as the communication network of choice because it provides an interoperable method to share data from one device to another. That doesn’t mean all devices speak the same application language. For example, SMTP (Simple Mail Transfer Protocol) was designed to communicate e-mail.
Does it make sense to burden SMTP with the ability to transfer files among devices? Probably not. That’s what FTP (File Transfer Protocol) is designed to do. And FTP works alongside SMTP and a rather large number of other task-specific protocols. Applying the scenario to the plant floor, products such as Zoneworx’s new (Temecula, Calif) Pathways and Opto 22’s (Temecula, Calif.) SNAP I/O , communicate multiple protocols, such as Modbus TCP, HTTP, ActiveX, OPC, and others, over Ethernet.
To expect one gargantuan protocol to cover all possible data types across an entire enterprise is ridiculous. This is where the plant floor could benefit by borrowing a page from the IT side of the business (see CE , Dec. ’99, p. 33 and p. 45).
Regardless of how it’s achieved, making plant-floor assets an integral part of the enterprise’s digital nervous system is a "must do" to eliminate variability and improve responsiveness to customers. Waiting for another new standard or "promising" new technology introduces one more source of variability, and who needs that?
A best-of-breed solution contains ERP, MES, and control and automation products that make the best use of open standards to link business processes and best fit your company. Choosing just such products and technologies is the best way to use what’s best today and be able to change to what’s best in the future.
Demand flow manufacturing improves quality and flexibility
‘Western corporations have pursued a manufacturing philosophy based upon traditional, scheduled manufacturing and MRP (Material Resource Planning) systems. To remain competitive in a global marketplace, manufacturers must move to demand based manufacturing," says John Costanza, father of Demand Flow Technology (DFT) and author of the book "The Quantum Leap in Speed to Market" (John Costanza Institute of Technology Inc., 1996).
Areas that differ between scheduled manufacturing and demand flow manufacturing include:
Philosophy;
Strategy;
Techniques;
Objectives; and
Resource utilization.
Scheduled manufacturing plants are functional departments that draw raw materials from and return subassemblies to central stores resulting in large inventories in anticipation of customer demands.
Product assembly is scheduled and routed through another functional department that draws additional raw materials and subassemblies from central stores to produce a customer deliverable product.
Throughout the process, materials are tracked in and out of central stores, inventory levels are closely monitored and controlled, quality is checked at the end of assembly, and significant department-to-department paper transactions occur between functional islands.
Demand flow is simpler
Demand flow manufacturing is much simpler. Its focus is to eliminate or minimize non-value-added work while emphasizing quality at the machine and/or employee level. Demand flow’s objective is to build a high-quality product in the shortest possible time, at the lowest possible cost.
A facility using demand flow manufacturing does not place all milling machines in one area, for example. Machines are located throughout the assembly line and parts and subassemblies are produced at the point of use. As parts are produced and used, raw materials are replenished using a Kanban system. Kanban is Japanese meaning a communication signal.
In demand-flow manufacturing, Kanban provides a physical signal used to pull products and material through and into the process. Kanban replenishment is a key benefit of adopting demand flow manufacturing for companies like NACCO Materials Handling Group Inc. (NMHG, Danville, Ill.), a company which manufactures Hyster and Yale internal-combustion engine forklift trucks in the 7,000 to 13,500 hp range.
Like many companies today, NMHG’s challenges include:
Better quality;
Reduced lead time;
Increased product mix (22 models and 1,500 options);
Reduced inventory; and
Greater scheduling flexibility.
After months of careful analysis, working through labor changes with union representatives, development of new supplier relationships, and a shutdown that completely gutted and reassembled the plant floor, NMHG returned to production as a demand flow manufacturing facility capable of producing a forklift truck every 17 minutes.
Raw material appropriate, for NMHG’s current production schedule, is located in double-deck racks at each manufacturing/assembly location. Attached to each container or pallet is a barcode tag with quantity, location, and other information. When a raw material container or pallet becomes empty, it is moved from the lower rack to the upper rack. This signals a request for replenishment. Depending on the type and quantity of raw materials, replenishment may be required in a few hours, or a few days. For example, only a few production hours worth of mounted rubber tires reside at the assembly station, but three days worth of lug nuts are on hand.
NHMG isn’t quite there yet, but Pete Meeker, procurement manager explains his vision, "Once we fine tune our detailed sequencing and combine it with Kanban replenishment, we intend to streamline supply chain management and reduce raw material and subassembly inventory even further. We have started working with vendors to eliminate boxing and reboxing through use of reusable containers. We have already learned reusable containers improve inventory integrity and we’re confident once we can repeatedly validate daily inventory we will be able to eliminate annual inventory shutdown and turn those days into manufacturing capacity."
Gary Nelson, NMHG’s manufacturing engineering manager says, "DFT is all about change. If a company’s mindset won’t accept change, DFT won’t work. NMHG’s approach toward implementation of DFT includes the need to:
Gain commitments from the entire organization, from ceo down;
Standardize processes and eliminate waste;
Develop new business applications;
Prepare in detail and train exhaustively;
Adopt a flat bill of materials approach;
Make Kanban signals as visual as possible;
Know the process backwards and forwards; and
Continuously involve marketing."
The numbers provide proof of the change to demand flow manufacturing. NMHG’s Craigavon, Northern Ireland plant achieved the following:
Reduced lead times by 60% (from 5 weeks to 2 weeks);
Improved quality by 58%;
Increased on-time delivery by 32% (currently 99.8%);
Slashed work-in-progress inventory by 48%;
Reduced floor space requirements; and
Developed a more flexible workforce.
Demand flow technology appears to have put NMHG well on the road to maintaining a competitive global advantage.
For more information on DFT, visit
Enterprise integration gets easier!
In this era of Internet-based sales channels, shorter product life cycles, mass customization, and near zero inventory policies, there is no doubt about the importance of feeding enterprise information systems with real-time plant floor data. The issue is, just how easy are vendors making it?
Plant-to-enterprise connectivity is complex, but new standards, techniques, and products are beginning to ease the complexity factors. These new solutions serve as a critical conduit to connect and optimize applications serving the needs in areas such as:
Labor tracking;
Asset utilization;
Part tracking and product genealogy;
True capacity scheduling;
Quality management;
Root-cause analysis; and
Preventive and predictive maintenance.
Connectivity standards, products
The first step is to provide a way for data residing in one device to be available to other applications to develop an information repository.
Data from ID systems, proprietary controllers, programmable logic controllers, motors, valves, sensors, etc. is becoming easier to share because of new standard, product-based solutions using:
TCP/IP, Ethernet, and wireless LAN for networking;
HTTP, HTML, and XML for Internet transactions; and
OPC, ODBC, and OLE DB for interoperability.
Analytical tools
Getting the data into information repositories is only part of the problem. Making use of the data and information to create knowledge is another.
An increasing number of tools are becoming available to help identify, analyze, and find root causes. Tools available include:
SPC/SQC, OLAP, and Data Mining for generic quality analysis;
ERP, MES, CMMS, and EAM to meet built-for-purpose application needs; and
Hydrocarbon process, and die casting and ejection molding optimizers to provide industry-specific solutions.
Enlightened business and information technology managers understand the benefits and potential of using Internet-based and other open standards to deliver simple and affordable plant-to-enterprise integration. They are asking the tough questions, and a growing number of vendors are responding with innovative answers.
Phil White, vp and co-founder of Zoneworx
See Zoneworx new product release in the Products and Software section of this issue.
