Radan's CADCAM products are helping one of today's most impressive UK performers in manufacturing to further improve the flexibility and responsiveness of its production. Stoves plc is the only independent British manufacturer of cookers and was formed in 1989 following a management buy-out of Valor Cookers.

At its Liverpool factory, where cooker manufacture has taken place since 1925, the company produces a wide range of high- quality cooking appliances - electric and gas, built-in and free- standing - sold under the names of Stoves, Stoves Newhome and Valour. All are for the domestic and leisure markets.

While the scale and efficiency of its production capability has to be seen to be believed, the company's output figures do give an insight into its performance. In a factory employing 1050 people, products worth between £1.7 and £2 million are built every week, and 8.5 million sheet metal parts are made each year.

There are currently 3500 products in its ranges and of these 2500 will be in production in any one week. All of them are manufactured to customer' orders. That means a wide variety of products in a range of designs, sizes and colours are coming off the assembly lines in small batches. One-offs are very common.

Many products will be dispatched the day they are finished and up to 20 per cent will go directly to the end customer. For its larger account holders, the company offers a seven day lead time. With such a wide range and such small batch sizes flexibility in production is the key to success.

Maintaining this impressive output performance calls for equally impressive setup at every stage of the production process. Flexibility of both people and equipment enables it to change production and products very quickly. Some £20 million has been invested in the factory in the past nine years, centred around flexible manufacturing equipment.

A key ingredient in getting that flexibility is programming the many CNC punching, forming and cutting machines that are kept busy producing in small batches the wide range of sheet metal components that form a large part of the products. And that is where Radan software is increasingly proving of value.

Radan's Radpunch/Radprofile and Radbend software is running on two PC work-stations and has been in use since 1997. It replaces three programming systems each previously dedicated to one make of sheet metalworking machine. As a result of the change says Stoves' associate director of manufacturing, Paul Rampling:

`We now have the benefits of data reliability. Radan enables us to programme more efficiently and reduce the number of errors. We can update products quickly and pass information back to design. Being able to make changes quickly is important because we are introducing 30 new or modified models every week.'

Currently the Radan system is being used to programme 10 machines. These are nine Amada and one FinnPower CNC sheet metal machines; two are laser profiling machines, one is a combined punching/laser machines and the rest are punching machines. Four Walker side-panel forming lines are also being linked.

This ability to integrate the programming and control of all existing and any future sheet metalworking machines was the first requirement in selecting a new programming system. Of the problems experienced when the existing machines now linked by Radan had their own programming systems, Paul Rampling says:
`Things were very complicated because we were constantly moving work around, trying to balance production. It was a minefield because of the numbers of changes being made; we always had to watch that we were conforming to the requirements.'

At that point Stoves knew it has to integrate all this production of sheet metal parts. In 1997 it began looking for a programming system that would do that and greatly improve efficiency in the process. While speed was important, Paul Rampling recalls that, as with the selection of machine tools, the most important quality looked for was integrity.

`Having done our research and spent time considering which system to go for, we knew that Radan was the best system to give us the flexibility we needed. Other systems would have restricted us in doing what we have to do on a daily basis. We cannot wait until tomorrow for what has to be done today.'

Visiting other Radan users confirmed this was the system. It took Stoves six months to make its choice and place the order which, as Paul Rampling put it `is a long time in Stoves business.' Before placing the order Stoves went through a number of issues with Radan to ensure it would get what it needed in the short, medium and long term.

It needed to be sure that programming times would reduce; they have been, to the extent that people have been freed up to do other jobs. Also because its spent £5 million last year on sheet steel it wanted to improve material utilisation, and it has. The variety and quantity of sheet metal parts also makes dissimilar nesting using Radpunch a valuable feature.

Good metal utilisation, and with it reduced scrap, forms part of the company's fundamental three-part operating policy by which aims to perform well in terms of quality, safety and environmental responsibility. As a result waste management plays an important part in the way the business is running.

`Again we saw Radan as being a tool we could use to improve that. Our intention is to push the Radan system hard to see what more we can do to improve costs and productivity, and generally use it to develop all aspects of the business.'

The ability to reduce errors in production was another feature looked for. The integration so far achieved using Radan has meant all-but eliminating the programming and tooling errors that used to come from moving work between different machine and using different programming languages and routines.

`Previously we were starting to make too many errors. It was making people very nervous, and it was having an impact on the business. Now we can count on one hand the numbers of mistakes we make. We have the old systems as back-up but I doubt we will use them again because we get such a good response from Radan.' System reliability backed up by good support from Radan was also of primary importance. The company tries to be self- sufficient in maintaining its equipment, with electrical and maintenance engineers able to solve most day-to-day problems. But specialist support is also relied on when necessary.

`We need systems to be reliable but we run three shifts a day so that when we do have a problem we need to be sure of support 24 hours a day. And we've had that from Radan. Because we don't carry stock, the minute we don't have the backup is the minute our production is in jeopardy.'

The Radan system is also integrated with the company's Pro- Engineer CAD system on which its products are designed. Not only is data drawn down from the CAD system so that parts can be programmed; information about changes made to parts during programming can also be fed back to the CAD system.

`When changes are made in manufacturing we don't want to wait while we get formal design approval before implementing it. If we have a problem we sort it out at the source. We do get the okay from the designer but we don't wait for them to make the changes before it happens. That is not in our culture.'

The company is now looking to the next phase of automation. Within the next year Paul Rampling expects to be installing flexible blank- or coil-fed lines for punching and bending sheet metal panels as alternatives to present punching and bending technology. He has already established that the Radan system is fully compatible with these new generation machines.