Seiki Flexlink puts you in the picture

Every production managers quest must be to generally improve production efficiency - not so easy when small batches are concerned. But that was then; now MWP looks at a new system that redefines your power to control performance.

Over the past ten years I've watched batch sizes steadily fall as companies move into an age where it is no longer profitable to stockpile, tying up valuable space and resources. Led ultimately by the automotive giants, smaller companies are finding working to the Japanese philosophy of 'just in time the only way to remain profitable. Response and lead times are now critical. However, as I'm sure many of you have found out, working to this strategy quickly reveals the shortcomings of conventional working practices. You cannot simply reduce batch sizes, clear out the stock rooms and go home whistling tunes.

The ratio of set up time to run time will change drastically, requiring you to review your entire production process. Issues such as tool availability, data transfer, production control, communication and maintenance become paramount. Non-productive time, which can easily be as high as 70%, is almost entirely attributed to a combination of these factors. It's for this reason that software developer Seiki Systems compiled its very successful modular suite of Windows shopfloor management and DNC programs, namely NC Program Manager, Direct DNC, Networked DNC and Advanced Networked Manufacturing System. The suite provides technical data to the operators such as drawings, tool lists and setting instructions and production details to the managers (please refer to my article in September 1998 MWP). However, as is nearly always the case, things have moved on - considerably in this case. In short, the emphasis has shifted from responding to questions like 'what can you do to get our performance up?' (the answer being to install one of the above 'select and grow' solutions); to answering more complex questions like now we can see the problems, what can you do to help us avoid them?'

This, of course would make an ideal opening for a Gypsy fortune-teller; however I feel you would find Seiki FlexLink somewhat more reliable. It's not a crystal ball; it's a clever integrated software/hardware product that keeps production managers in the picture, wherever they might be. The real time monitoring functions are so informative you can see things coming, or at the very least respond promptly if the unthinkable happens. Seiki FlexLink, like its predecessors, comes in variants allowing you to grow the system with your company, the common feature being true two-way communication between the machine controller (Hitachi Seiki's Sigma) and an external PC. This in itself is not revolutionary; there are examples of controllers with in-built PC boards in the marketplace. However by having an external PC, Seiki Systems and Hitachi Seiki have overcome the problem of upgrades. It's easy to change your PC for a faster model, not so easy to change the machine's controller - there's the reliability issue as well. However, where the Seiki FlexLink systems really score is data handling and alarms.

'We have listened very carefully to what our customers have to say about production needs and responded' says David Trowell, Seiki Systems general manager. 'All the development work is done in house. We even managed to get our Japanese counterparts to modify the machine controllers to suit our needs - they are very excited about what we are doing here in Brighton.'

THREE CHOICES Seiki FlexLink DNC, which consists of an office based PC linked to the shop floor CNCs via a bi-directional Ethernet network, is what Seiki Systems describes as its entry-level setup. This, unlike Microsoft explorer, is a tamperproof link allowing users to download and return NC programs without the risk of introducing unqualified changes to the master copies. Level two, Seiki FlexLink Production Manager, has a similar setup to Seiki FlexLink DNC but has the additional ability to display the MRP queue and manufacturing data. Information such as current job status and alarms is fed back to the production manager who monitors the situation and responds accordingly. Level three, Factory Manager, really puts you in the driving seat taking advantage of just about every innovation I've seen in computing today.

Each CNC machine tool is attached to its own PC via an Ethernet link, rather than RS232. From here the PCs can be integrated into the general company network, a PC in the manager's office - or whatever. The machine tool becomes transparent, allowing data to be written to, or read from it as if it was just another office computer (made possible by the hardware modifications mentioned previously). The upshot of this is that the machine can tell you exactly what state it's in, ie waiting for a coolant change, new tooling, next program, speeds/feeds etc, in real time allowing managers to respond to production loss in an instant.

The machine status information is derived from a combination of automatic machine monitoring and operator input. Data can also be monitored over time in much the same way as Seiki Systems earlier product - Advanced Network Manufacturing System - allowing managers to see overall trends and identify areas that need rethinking, le tooling strategies, reasons for lost productivity and maintenance schedules, etc. For the operator it means a large user interface with graphic help screens, toolpath verification, video of set-ups, NC editors and even video conferencing if you have a camera fitted and Microsoft NetMeeting. The possibilities are endless -I hear Tomb Raider II is worth a whirl!

Seiki Systems Network Manufacturing System, has also been enhanced using technology from Seiki FlexLink, but is not as flexible as having a PC directly interfaced with the controller PLCs - however it does have the advantage of being available for any machine tool with an R5232 port.

FURTHER ENHANCEMENTS
As with the earlier systems, event monitoring is a key aspect of Seiki Systems product. This was presented as a text logbook' but many requested a more readable format. To address this, Seiki Systems has re-presented the data as a permanent 24-hour graphics display with moving bar(s) representing the machine(s) history. By simply positioning the mouse pointer at a point along this bar, the production status at the time can be accessed making it easy to look back over problem areas. To assist with this investigation and to show where current problems are being experienced, Seiki FlexLink gives you the ability to layout the machines as a virtual shop.

A constant e-mail style chat line improves communication between the office and shop floor. Selecting jobs is as simple as pressing Queue' on the controller. The operator is presented with the output from the company MRP system that is bang up to date' and not a week old copy. From here all he/she has to do is select a job from the list and press 'Start'. The system will record everything that happens during that job, display all the setting information and provide the operator with the facility to record problems such as 'distorts' if clamped at over 2Olbs, etc, this information is then readily available when the job is next run. A system engineer initially sets up the directory paths.

The operator is in touch with the design office, tool setters - whoever. Graphical details and 3rd party verification (eg CGTech) can be simply downloaded and run. The manager knows what job the operator is doing, how long he/she has been doing it, how long it will take, and can view real time parameters such as current spindle speeds, feed rates, overrides, etc. This means no more problems with operators setting the feed rate to zero and popping off for a fag - cheating the system is impossible. You can think of it as a sort of flight recorder if you like. Managers will have access to average time per part, scrap rate, batch size and setting time. Most managers will want to feed any savings back into the MRP system as revised times.

In the event of an alarm situation the computer will override whatever the manager is doing, prompting for immediate attention - who likes doing accounts anyway? Alarms can be configured for anything and directed to the relevant department managers. For example, a tool breakage would generally be directed to the tooling manager.

By now you are probably thinking: 'what if the manager is not in his office?' Not a problem! If the department manager does not pick up an alarm, the system will go through a set of pre-configurable escalating sequences until a response is gained. This sequence would typically start by flashing an alarm light in the production department followed by sending a fax to the department responsible. If this fails to alert anybody's attention a message is sent to the manager's mobile phone. This works in much the same way as sending a message to a friend, which is appropriate - this system is your friend; the next port of call is the managing director's office, and he's going to be none too pleased if four response calls have been ignored. I guess if things do go this far you can always set the system up to make the MD a cup of coffee - it might help - but there's really no excuse. The system works by sending a code to standard X1O switching gear. All you have to do is set up the codes for each switch and telephone/fax numbers.

The audio-visual support functions are comprehensive, taking full advantage of modem networking capabilities and packages such as Paint and Whiteboard. For example if an operator is having a problem with a component he/she can contact the manager via the NetMeeting facility. The manager can then open up a picture of the component. This will immediately appear on the operator's screen allowing the area of concern to be highlighted and discussed. This might seem a little impersonal, but just think of the time it will save. One final point I would like to bring your attention to is the detailed maintenance possibilities made available by such controller/internet configurations. Once you have a controller that is capable of downloading system information over the internet all the engineer has to do is log onto the system and page through it until the fault is identified. You do not need special software; Microsoft NetMeeting, which comes free with all 95/98/2000 Windows operating systems, is all you require. You could even set-up an alarm call for the engineer. As I mentioned in my prior feature, this really is the shape of things to come; the question you should be asking yourself is - 'can I afford to do without it?'