A company is offering a unique and less-invasive cable replacement technology, which could prove useful for carriers looking to replace their aging copper infrastructure with fibre, without incurring the cost and disruption of digging up the old cabling.

Kabel-X uses a patented method, which is already used in Germany and Austria. Essentially it strips out the inner core of a copper cable, so that a replacement fibre optic core can be inserted in its place.

"A typical cable has an inner core of copper (it varies how many pairs), then some kind of wrapping around the inner core, then the outer jacket itself," said Simon MacDonald, founding partner at Kabel-X.

According to MacDonald, Kabel-X injects a patented fluid into the ring space between outer jacket and the inner core.

Once the fluid emerges from the other end, the engineers equalise the pressure to make sure the fluid has got around all of the cable to make sure it has separated (from the outer jacket). Kabel-X then uses a winch to extract the inner core. The process leaves the empty conduit (outer jacket) in the ground. This emptied outer jacket is then ready to house the mini ducts and fibre.

"We have the process working so effectively, that in some cases, we don't need to winch the cable at all, as the pressure from the pump forces the cable out, as it is so well greased," said MacDonald.

Once the inner core has been removed, Kabel-X can immediately start threading fibre into the outer jacket, or can drag mini ducts into the outer jacket, whilst pulling out the old core. Once the mini ducts are in, you simply connect them up.

MacDonald says that Kabel-X can replace cabling over a distance of up 250 metres a time. This makes this process ideally suited to urban areas, where the replacement of existing cabling often relies on digging up the road, causing major disruption and adding greatly to the cost.

"It is unlikely that it will be more than 250 metres between man holes for a ducted cable," said MacDonald, referring to typical urban environments. "Manhole covers are unlikely to be more than 250 metres apart. Indeed there are usually less than 200 metres apart."

"In cases of direct buried cable (like in the countryside), we would only need to dig down every 250 metres instead of digging massive trenches," he said. "This is applicable where there might be roads, farmers fields, or conservation areas, where large scale construction is prohibited or tightly controlled."

MacDonald says his technology will work around bends, up and down buildings. However he admits that the technology is not suitable for use in every case.

"We are not saying that," he insisted. "But the fact is, in some cases, the cable can be trapped in ducts, because of silt, subsidence, or the environment means that it may not be possible to extract the cable, but it is possible for us to pump our fluid into the ring space. Our process allows for the extracting of the core, and then allow for the recycling of the copper."

This cost saving aspect to the technology is increasingly important, as copper costs have tripled over past four years. Nowadays, copper costs over $8,000 (£4,000) per ton, and in some countries, such as South Africa, theft of copper from telephone lines is a frequent occurrence.