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Wire & Cable ASIA – July/August 2010 42
Double twist stranding of
instrumentation cables
Maschinenfabrik Niehoff’s DSI series of double twist stranding machines and
additional equipment can be combined to manufacture all types of data and
special cables, including LAN cables of all existing categories and even future
generations.
An example application of the versatility of the double twist stranding line
is the manufacture of instrumentation cable for the petrochemical industry.
In this case, the cable consists of two flexible conductors with polyethylene
insulation, two fillers and a drain wire (ground).
During the stranding process, the inner part of the cable has to be wrapped
with three film layers. All elements of the cable are assembled in one process
on a stranding line which is composed of three payoffs type ATP 630, three
payoffs type ALB 600, a pre-twister type VVD 180, and a DSI 631 type double
twist stranding machine.
The ATP 630 tangential payoffs are designed for the uncoiling of cables,
insulated single conductors, pairs and quads with a maximum diameter of 4mm.
Each payoff is driven by a dancer-controlled spool drive with adjustable wire
tension; the maximum haul-off speed is 300m/min. In this case, the units were
used to payoff the two flexible insulated wires and the ground wire.
Maschinenfabrik Niehoff GmbH & Co KG – Germany
Fax: +49 9122 977 155
Email:
Website:
ATP 630 type tangential conductor ❍ ❍
pay-offs