WCA September 2014

Technology news

100 per cent quality assurance at production

SIKORA offers a complete product portfolio of inspection and sorting as well as measuring and control technology for online quality assurance of energy cables. 1. The purity of XLPE pellets as they are used for the insulation of medium, high and extra-high voltages cables as well as for on- and offshore cables is a decisive characteristic for the quality of the end product. Damages caused by breakdowns due to contaminated material can easily run into the millions. Therefore, the production of highly clean material as well as the continuous detection and sorting out of contaminated pellets before they get into the extrusion process is of essential importance. With the purity scanner, Sikora provides a system for 100 per cent online inspection and automatic sorting of PE pellets. The purity scanner intelligently combines X-ray technology with an optical system. This allows the detection of metallic and organic impurities of 2mil (50μm) in the pellet itself and on its surface to 100 per cent. Contaminated pellets are detected and sorted out in order to ensure that they do not get into the extrusion process. The application of both technologies is unique, and is exceeding previous solutions on the market. Due to the specially developed X-ray technology, the purity scanner is the first system that inspects transparent and coloured (eg black) pellets as well as semi-conductive XLPE material for impurities and sorts them out automatically. 2. In a CV-line, for example, a CSS 2 (cleanliness scanning system) is installed for real time monitoring and detection of impurities of the polymer melt. The flow channel between main extruder and the crosshead is equipped with sight glasses and an optical CCD colour camera system, which inspects the insulation material. The CSS 2 detects contaminants down to a size of 20μm and distinguishes between metallic contaminants, scorches and ambers of selected sizes. It provides information as to when the production may start after bleed-off, respectively as to when it is necessary to stop production, because of an extensive number of detected contaminants.

❍ CV- and VCV-line with Sikora inspection and sorting as well as measuring and control technology for reliable quality assurance during production of energy cables

available immediately after starting up the line. The system is used in catenary and vertical lines. 5. While the X-Ray 8000 NXT provides information for a fast centring and direct control, the X-Ray 8700 NXT supplies precise quality data of the final product. The X-Ray 8700 NXT measures the diameter, wall thickness and eccentricity and is suitable for all cable types with solid, stranded or Milliken conductor and with single, double or triple layer insulation. With the use of the X-Ray 8000 NXT at the beginning of the line for collection of the hot measuring values and the X-Ray 8700 NXT at the end of the line for measuring the cold values, three shrinking values are analysed for every insulation layer of the cable. Consequently, an optimum process is assured. Sikora AG – Germany Website : www.sikora.net

3. Sikora’s product range for energy cables also includes the Ultratemp 6000 which measures the temperature of the PE melt during extrusion on a non-contact basis between the extruder screw and the crosshead. Besides temperature determination, the Ultratemp 6000 detects inhomogeneities in the melt. Early cross-linking after screens which may lead to ambers or scorches in the material can be avoided by this reliable ultrasonic temperature measurement. The device optimises the output of a planned production time. 4. The X-ray measuring system X-Ray 8000 NXT is installed in the moving part of the telescopic tube directly after the crosshead for precise measurement of the wall thickness of all three layers (concentricity, diameter and ovality) directly after the triple crosshead. Measuring values for centring and control are therefore

Cosmos North America Inc’s innovative split-thread air wipe AWM 71 features include effortless threading, extended life service, low air consumption and knot passage. A tension spring and the surrounding air pressure keep the air wipe closed during wiping but it will open readily to pass knots. A performance data sheet registers the air consumption at delivery, and the wear-bearing components carry a two-year warranty. Cosmos offers four wiping cylinders of bore diameters 2, 3, 4 and 5mm for wiping at optimum efficiency of wire diameters 1.4, 2.4, 3.4 and 4.4mm. Wiping wires with diameters less than the optimum diameter will reduce efficiency but will not have any adverse consequences on the wire. Cosmos North America Inc – USA Website : www.cosmos-na.com Threading with little effort

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Wire & Cable ASIA – September/October 2014

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