Introduction

Whether installed new or incorporated into an existing line, the triple-twist® process from Gauder Group, of Belgium, allows up to 50% higher production speeds than conventional LAN pairing lines, while yielding the same cable quality. To enable cable producers to maximise the triple-twist process, Gauder has introduced a new series of equipment offering all the benefits of backtwist technology, combined with those of the company’s popular DVD 560. More than 400 of these units have been sold.

Among the advantages of the new Model VTT 560 for Cat. 5, 6, and 7 LAN cable manufacturers are: stabilised impedance, superior consistency, and hydraulic loading platform and pneumatic pintles for easy reel handling, as well as an integrated electrical cabinet and auxiliary stand-alone equipment. The backtwist rate is continuously adjustable by way of the operator’s control panel.

This article highlights the basic principles of triple-twist technology from Gauder, a group already well known as specialists in the design and manufacture of double-twist units.

Increased productivity from lower investment

Gauder’s Model VTT 560 vertical triple-twist LAN pairing unit offers integrated backtwist (essentially, no-twist) pay-offs. An all-in-one design, the VTT 560 handles speeds up to 6,000 twists per minute. The pay-off may be utilised as a twinner, joining two insulated wires by means of the bow cabler principle (Figures 1 and 2).

Figure 1: Gauder Group VTT 560 vertical triple-twist machine

Figure 2: The new VTT 560 wire path

Principle of the triple-twist process
The VTT 560 vertical triple-twist machine acts earlier in the process than a standard double-twist pairing machine, whereby two twists are added on the pair in order to produce three twists per bow revolution. Instead, the VTT 560 generates a first twist on the pair of wires without having imparted any twist to the single wires themselves.

The difference is apparent in the output. For Cat. 5e pairs, some 6,300 twists per minute are produced with the VTT 560, as compared with 4,500 twists with a standard 560mm double-twist twinner. Category 6 pairs can be produced at speeds of up to 6,000 twists per minute (versus 4,000 twists on a standard 560mm double-twist twinner) (Table I).

Table I

Given these higher (up to 50%) speeds, fewer machines furnish the equivalent production capacity. Accordingly, users of the VTT 560 vertical triple-twist unit can expect to see cost and time savings in total investment, floor space requirements, installation, maintenance, power consumption, commissioning, shipment cost, etc.

Double-position payoff
Similar results can be expected from the double-position payoff from the Setic-Gauder Group. Type DVDTT 560 R also activates its triple twist earlier in the production process than current models of the standard double-twist machine. This machine raises running speeds from 1,500 up to 2,200 twists per minute in the production of Cat. 5 through Cat. 7 cables. The twinner can also be used for other products (Figures 3 and 4).

Figure 3: Setic-Gauder Group double-position payoff Model DVDTT 560 R (left) with model TA 560 Ni (right)

Figure 4: Schematic drawing of the Model DVD TT 560 R with model TA 560 Ni

The Model DVDTT 560 R also permits the use of an existing standard double-twist twinner for high-speed (6,000 twists per minute) Cat. 5/6/7 pairing. By increasing total production capacity without the purchase of an additional twinner, the unit substantially reduces investment costs.

Cable quality improvement

The increase in productivity with the use of the model DVDTT 560 R does not impose any sacrifice in quality. As Figures 5a and 5b demonstrate, the NEXT (near end crosstalk loss) level remains very low with the DVDTT 560 R. Impedance stability is also very good (Figure 6). These results mainly are generated by:

• Backtwist (no-twist) effect on the two single wires. The pay-off unit works as a bow cabler to twin the two wires. The pair is produced at pay-off output without any twist on each wire;
• Payoff tension control. Wire tensions are equal at the twinning point. Using two load-cells, the machine controls two different paying-off tensions so as to equalise tension of the wires at the twinning point;
• Optimised wire path (reduced bow balloon) and dancer-regulated take-up tension;
• High-accuracy lay length, controlled by a motorised capstan driven by a brushless motor;
• Use of a middle capstan at payoff output to reduce the tension of the pair before entrance into the double-twist take-up unit.

Figure 5a: UTP Cat.6 production: NEXT level remains very low

Figure 5b: UTP Cat.6 production: Good impedance stability

Figure 6: Backtwist (no-twist) effect

Cable quality with the Model DVDTT 560 R is similar to that obtainable from a double-twist twinner operating in combination with a backtwist pay-off. Pairing high-quality Cat. 6 cable at 6,000 twists per minute is a production reality. Thousands of kilometres of cable have been manufactured on this type of machine, and the quality and consistency of the product are appreciated by the leading LAN cable producers who have availed themselves of this process for over two years.

Floor space reduction

To return to the VTT 560, no effort has been spared to render it - together with the well-known TA DVD 560 version - a hallmark of compact and user-friendly machinery. Among its features:

• Two pay-offs and a pairing unit placed side-by-side in a safe and soundproofed enclosure on the same frame. All operations and servicing are readily performed from the front;
• Vertical shape for the three cradles;
• A built-in electrical panel on sliding guides so that machines can be installed back-to-back and side-by-side. Operations can be carried out directly with a clear view of effects on the machine that is running.

Figure 7: Space saving with VTT 560

Given the very compact design of the VTT 560 (and the fewer units required, as a result of higher pairing speeds), floor space requirements are reduced by up to one-third. As demonstrated by Figure 8, an area of some 203m2 is necessary for ten double-twist twinners with integrated payoff. In contrast, an area of only 66m2 suffices for placement of seven VTT 560 units offering the same production capacity.

The DVDTT 560 R variation also includes vertical cradle and bow, and an electrical cabinet located on the sliding frame. This permits either back-to-back or side-by-side positioning.

Other features of triple-twist machines from Gauder Group include:

• Easy maintenance thanks to AC bow motors and take-up reel and capstan brushless motors. The maintenance programme is displayed on the operating panel;
• User-friendliness, as all production parameters can be adjusted from the touch-screen colour panel: lay length, no-twist (backtwist) rate, pay-off tension, takeup tension, speed, production length;
• Easy, safe, and quick handling of the reels, with the use of hydraulic loading platforms and pneumatic pintles;
• Quick installation (less than two hours for the VTT 560)
• Handling of the machine in one part (including soundproof cabinet and electrical cabinet)
• Plug and play design.

Figure 8: Gauder Group VTT 560 vertical triple-twist machine needs less space than a conventional unit

Conclusion

For more than two years now, triple-twist twinners from Gauder have been producing LAN pairs in major cable manufacturing plants. With the 60-plus triple-twist twinning lines sold by Gauder all giving satisfaction, their productivity and cable quality benefits are defining the triple-twist as the new industry standard for LAN cable pairing. Other types of machinery are designed and produced by the Setic-Gauder Group, of France, where demonstrations and trials may be arranged. This affords the prospective buyer an excellent opportunity to examine the wide array of Setic-Gauder machinery currently available for LAN production, and to preview units, now in the design stage, that are about to go into development.

Gauder Group
Rue de la Révision 93
B-4032 Chênée (Liège) - Belgium
Fax: Int’l +32 4 367 87 98
E-mail: [email protected]
Website: www.gauder.be