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Wire & Cable ASIA – September/October 2007

56

Nove ber/De ember 2 13

www.read-wca.com

Standard cables and similar products with a diameter of

minimum 4mm can be wound with very high quality. Steel

wires and steel tubes with even smaller diameters can also

be wound using the precision winding unit.

A prerequisite of a perfectly wound reel is that the reel

itself is of high quality. The better the quality of the reel, the

easier it is to achieve a satisfactory winding of the product.

Safety

Today it is sometimes necessary to manually guide the

cable onto the reel and this process can be both time

consuming and dangerous.

The person guiding the product will often have to focus

exclusively on the winding process, and depending on the

product he may have to stand immediately in front of the

take-up.

Standing close to the take-up involves the risk of being

jammed between the product and the reel, with serious

personal injuries as a result.

As health and safety requirements become more stringent,

it is increasingly difficult to carry out the manual guiding

of cable in front of the take-up, because it is completely

fenced in.

Even when it is possible to manually guide the cable onto

the reel, the distance from the operator to the take-up may

prevent a perfect winding.

Pulleys

To achieve the best possible control over the product, it

is important to guide the product as close to the reel as

possible.

It is a key parameter to have as little distance from the

pulleys guiding the product to the reel as possible.

The product is guided through a set of pulleys, which are

dimensioned according to the diameter of the product.

Because of the compact size of these pulleys, the distance

to the reel can be minimised. Furthermore, the pulleys are

shaped so that they are able to position the product very

close to the flange.

The guide arm is fitted with sensors detecting and

measuring the distance to the flange, and these sensors

ensure automatic change of traversing direction when the

cable is next to the flange.

The software controlling the precision winding unit is

developed to optimise the quantity of product on the reel,

eg by avoiding large gaps at the flanges when changing

winding direction. During winding the guide arm turns 180

degrees so that the pulleys are always able to run very

close to the flange.

The flange detection system makes it superfluous to

key in new parameters when changing to another reel

size. The precision winding unit automatically adapts the

traversing to the mounted reel and it is not necessary to

change end-settings.

When a layer is completed and the next one prepared,

the guide arm moves up the ball rail by a distance equal

to the product diameter in order to keep the product in its

horizontal position.

The inlet of the precision winding unit consists of a

number of pulleys, which are mounted in a funnel position

and thereby apply a minimum amount of pressure to the

product, even though the line height changes as the reel

becomes full. Using the precision winding unit makes it

possible to fill the reel to the edge of the flanges.

Reels

It is important to position the product as close to the

flanges as possible. Generally, it is recommended

that flanges do not deviate more than half the product

diameter.

If, for example, a product has a diameter of Ø12mm,

the flanges must not be more than 6mm off (±3mm).

This means that the smaller the product diameter, the

higher the demand for perfect reels.

For a number of years Roblon has supplied take-ups

with integrated precision winding units, capable of

handling reels ranging from Ø380 to Ø1,400mm with

a max gross weight of 1,800kg, and winding products

ranging from Ø3 to Ø16mm.

Some of the take-ups have been in use for the last

15 years, winding steel wires with a minimum of

maintenance, and this underlines the durability of the

technology.

Guide arm

Inlet pulleys