WCA March 2011

Cable production

Double bonus from Niehoff

One industrial multi-taping example is the production of an instrumentation cable for the petrochemical industry. The cable consists of two flexible conductors with polyethylene insulation, two fillers and a drain wire.

Manufacturers need sophisticated and cost efficient pro- duction equipment combined with reliable and competent technical assistance. Growing requirements on the tech- nological properties of data, communication and other special cables make such equipment absolutely essential.

The ALB 600 payoffs with tape forming used in this case can be operated with payoff spools or film disks. During the manufacturing in one process, the inner part of the cable is covered with three film layers – a polyester film, an aluminium/polyester film and another polyester film – under reduced, controlled and homogeneous film tension. This is done in a pre-twister which is placed between the tape payoffs and the DSI stranding machine. The pre-twisters of the VVD series have been developed for the cost-effective production of insulated wires, pairs, quads and cable cores in 5 or 7-conductor

Double twist stranding machine DSI 631 ❍ ❍

design with three or more films applied in S or Z twist direction by double twist stranding machines. The speed can be infinitely controlled. For certain applications, the conductors must be backtwisted before being stranded. The Niehoff double twist backtwist pay-off type ARD 630 D is designed for backtwisting of single insulated conductors with a diameter of up to 3mm, pairs and quads. The back twist ratio can be regulated from 0 to 100% or even higher if required. The lay length is infinitely variable from 10 to 120mm, and the number of twists is infinitely variable up to 3,200 twists/min.

Niehoff offers both a wide range of modern machinery and an immediate customer service. The DSI stranding technology: The field-proven double twist stranding machines of the DSI series (DSI 631 and DSI 1001) are built for a wide conductor cross-section range and a maximum strand diameter of 8.5mm or 15mm. The DSI stranders available in left and right-hand versions feature the one bow design, which results in a significantly reduced energy consumption and noise emission. Manufacturers benefits evolve as well from class IE2 energy-saving AC motors with electronic control and energetically optimised components, and a contactless machine data transfer which

minimises maintenance and operational and material costs. The new machines and aux- iliary systems comply with the current safety regulations of the machinery directive RL 2006/42/EG and feature a completely new and func- tionally optimised machine design.

DSI 631-based special cable stranding line ❍ ❍

Versatile modular system : The DSI machines can be combined in a modular system with double twist backtwist payoffs, longitudinal tape payoffs, pre-twisters and other auxiliary systems. The profit is that complete stranding lines can be customised to manufacture all types of data and special cables, including LAN cables of all existing – and even future – categories with the utmost precision and quality at high speeds, either with or without back twist. Multi-taping, backtwisting and paring in triple twist mode – application examples Depending on line configuration up to three foils can be applied in-line on a cable under controlled film tension.

The tension is on-line controlled during the process, and the production speed is up to 300m/min. Optionally the double twist backtwist payoff can also be used to enable a paring process in triple twist mode. In this way the stranding speed and therefore the production capacity can be considerably increased and, as a consequence, the production costs can be reduced. Maschinenfabrik Niehoff GmbH & Co KG – Germany

Fax : +49 9122 977 155 Email : info@niehoff.de Website : www.niehoff.de

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Wire & Cable ASIA – March/April 2011