Introduction to Industrial Engineering
By Jane M. Fraser
Chapter 6
Design or improve a production system
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Data are being created in every organization. Such data include faults or breakdowns in the system (a machine tool just broke in cell 3, or Mike in purchasing has gone home sick) as well the details of every transaction (machining part X32 on machine 3 started at 9:30 am on 26 January 2006 and took 2 minutes and 3 seconds; checking patient 3789 into the hospital started at 9:30 am on 26 January 2006 and took 12 minutes and 36 seconds).
All data have the potential to be used for immediate decision making (dispatch Mary to replace the tool in cell 3; reroute Mike’s calls to Stan for the rest of the day) and for long term decision making (the times to machine small parts is less on machine 3 than on machine 4; let’s consider putting together a team of machinists to determine why this difference is occurring and to see if we can cut the machining times on machine 4).
Automation For Information from MMS Online talks about the importance of capturing and using information at all steps of the manufacturing process, often with an increase in profits at little cost.
“Instead of purchasing new capacity or new machinery, the plant realizes a potentially larger amount of capacity that formerly was going to waste.”
In Feedback From A CNC In Real Time Is...A "Significant Event" At Cessna from MMS Online Albert describes how an investment in retrofitting two CNC machines with standard PC hardware and Windows based software, linked to the company’s intranet, allowed information to be gathered and used in real time and in long term decision making.
In the Emergency Department at Parkview Hospital, physician orders are entered into the computer; such entry captures the order more accurately, avoiding problems of legibility as well as reducing errors due to drugs with words that look like or sound like another drug. Because physician orders (for drugs and for tests) are captured electronically, they are displayed immediately to the relevant staff; the filling of the order doesn’t have to wait for a paper order to be moved to the correct department.
When considering the use of information technology, IEs should consider the following principles:
Computer technology should not be purchased without thinking first about whether the processes the technology will support are really necessary. Focus first on eliminating unnecessary steps and on improving the efficiency of a process; then think about using information technology. Computer technology and software to support electronic routing of approvals for purchase orders might make sense, but first examine the process for approval of such orders; perhaps all the approvals are not needed. The improved process might not need computer technology.
Invest in hardware that allows the automatic collection of information, reducing the need for humans to enter data and allowing for more accuracy in databases. Point of Sale terminals capture sales data as the sales occur, enabling tracking of inventory and sales. In its manufacturing process, Fujifilm replaced a step requiring workers to enter a tracking number with a scan of a barcode, reducing movement by workers and increasing accuracy. In 2004 the Food and Drug Administration gave the hospital industry two years to meet a requirement that all drugs administered to a patient in a hospital be confirmed by scanning the patient's barcode ID and the barcode for the drug. Copeland Corporation uses bar codes to ensure that the correct products are shipped to a customer.
Barcodes continue in use, but the newer technology of Radio Frequency Identification (RFID) means that an object can be located from a distance, without the need for a line of sight to the object. In an article in Directions magazine, David Williams explains what an RFID tag is:
An RFID tag consists of a microchip and an antenna, often in the form of a tiny ribbon that can in turn be packaged into many forms, such as a label, or imbedded in between the cardboard layers in a carton. On the microchip is stored information about the product that the tag is affixed to, which can then be "read" when the tag passes within proximity of an RFID "reader," with that information being relayed back to a computer system that updates the location status of the associated product.
The railroad industry was a leader in the use of barcodes to track the location of rolling stock, and now they are leading in the use of RFID tags. RFID tags are used for automatic toll collection. Edinburgh, Scotland, uses RFID tags on buses to control traffic lights and reduce traffic congestion.
A product that is manufactured with an embedded RFID tag can be tracked through the manufacturing process, through the supply chain, through the sales channel, and even to the final customer. In 2004, Walmart announced that by the end of 2006 all suppliers would have to put an RFID tag on shipping crates and pallets. This article explains the challenges faced by a small manufacturer in meeting the Walmart mandate, but also the way the manufacturer will use the RFID tags to improve the packing and shipping process. RFID tags cost 10 to 100 times what barcodes cost, but as use of RFIDs expands, their cost is dropping. Some companies are now moving toward placing RFID tags on individual items as Levi is testing, but some consumers have privacy concerns.
When humans do have to enter data, use technology to make it easy, through touch screens, stylus entry systems, and wireless PDAs. Customers enter their own data when making purchase on the web. This article describes the use of Palm Pilots to have patients in a medical study enter data daily using a stylus. The data are transmitted by phone modem to a central databased.
Be sure that the computer technology you recommend, actually adds value for the customer. What is the contribution to efficiency, quality, or safety, and what, thus, is the contribution to customer satisfaction?
Interoperability is an issue for both hardware and software; computer technology and computer software from different manufacturers and from different suppliers may not work well together. Standards are supposed to reduce this problem, but a cynical saying is: "standards are great; everyone has one." Many engineering devices now have computer technology and software built in. This article talks about the movement of Coordinate Measurement Machines from inspection to in line monitoring of quality. Because the goal is to compare the design with the actual part, users have to be careful that their CAD system and CMM system will talk with each other.
Finally, when you are computing the cost of purchasing computer technology, include the cost of maintaining the system and of purchasing upgrades and replacements.