Edgecam, the market leading CAM system, has been instrumental in manufacturing parts for a new type of high voltage electric cabling connector.
Prysmian Cables & Systems is the UK's largest domestic manufacturer of energy and telecommunications cables and systems. Amongst its customers for energy cables is the National Grid, and countries including Saudi Arabia and Singapore. As well as both fluid-filled and dry cables, Prysmian also produces a range of high precision connectors, including a new product which is ahead of most others in the industry: a connector that joins fluid-filled cable to dry cable.
Dorrian Higgins, Process Owner, says: “We now have the capability to join high voltage fluid-filled cable to dry cable, ranging from 132kV up to 400kV.” Edgecam’s unrivalled ease of use and sophisticated toolpath generation played a major role in the development of the fluid-to-dry connector, as well as being an essential part of Prysmian’s manufacturing process to produce its range of connectors, from around 100 mm in length with a 40 mm diameter, to 500 mm in length with a diameter of 200 mm.
Prysmian’s connectors are manufactured from copper, silver plate or aluminium, depending on what the cable is made of. “We can also join aluminium to copper, which is another unusual process in the industry, but using Edgecam makes it easy for us.” The outside protective casings for their connectors are engineered from stainless steel, again machined using Edgecam.
Another essential function of Edgecam is to ensure the tolerances of all Prysmian’s high precision connectors are met. “As we’re making something that’s got a conductor connected to the cable the tolerance has to be very fine, around 50 microns.” Edgecam is used to produce 200 different components, and is especially valuable for new designs. “Whether it’s a completely new design or modifying an existing one, we’ll use Edgecam as we prefer to use the solid models to generate the toolpath. It’s more efficient and easier to use.” He says Edgecam gave a 40% reduced cycle time on a recent job, taking it down from ten minutes to six minutes.
Before Prysmian began using Edgecam about two years ago they did not have a CAD system, and had to generate the codes in a variety of ways, depending on whether they were using their Okuma, Fadal, Mazak, Alpha or DSG machines. “Now everything is so simple as Edgecam creates programs for each machine. It’s particularly useful going from the DSG, which is quite old, to the much newer Okuma just with the click of a button, instead of having to completely rewrite the whole program and working out the variables from one machine to another. The time saving is quite considerable. If we were to write the program manually it might take a day. With Edgecam it’s an hour at most.”
He says that as Edgecam is designed to cope with programming the simplest to the most complex components and offers full support for the latest CAD, machine tool and tooling technology, it would be extremely difficult to manage without it now. “We’ve been relying on it much more heavily over the last year, and our Fadal, Alpha and DSG machines now run 100% on Edgecam, the Okuma 90% and the Mazak around 60%. Edgecam has become an absolutely vital and integral part of our manufacturing operation.”
The programmer takes the solid model and imports it into Edgecam. Then it is orientated for the machine they are working on, either milling or turning. “Following that we do the standard feature find which is quick, convenient and easy to use – Edgecam finds everything we need the machine to do. The stock is added to the job so we can simulate the machine to see how it will look, and then we pick the tools for the features that we need. Again, this is very straightforward and any machinist can do it with the right training.”
Dorrian Higgins adds that once the tooling has been selected, the programmer goes through the machining cycles whether it be rough, milling, turning or finishing, and once they are satisfied with the tool paths the CNC codes are generated. “After that we print the Edgecam job reports for the machinist who’s going to set it and operate it. This shows them exactly what it’s been programmed to do.”
Another Edgecam feature which they find extremely useful is the ability to save the programs as job numbers with the part number and issue number. “As soon as the operator wants to download a program they check that the part and issue numbers match the ones they’ve got, so they can see at a glance that they’re using the latest issue, and not an old issue.”
The partnership between Prysmian and Edgecam began when the company offered a work placement to a French engineering student in his final year at university in France. It was the student’s idea to use a CAM package to streamline the machine shop, which was quickly taken on board by Prysmian’s management. “A very conservative estimate for the time it’s saved us in 2010 is around 950 hours, meaning our return on investment in the one year is £47,225,” says Dorrian Higgins. “It’s really helped us take the business to the next level.”