Extrusion International 5-2017

34 Extrusion International 5/2017 EXTRUSION EQUIPMENT Picture 1: SIKORA‘s X-ray measuring system X-RAY 6000 measures all hose parameters. At the monitor of the processor system ECOCONTROL 6000, the product data are being visualized heat exchangers for power plants or the transport of ag- gressive media. In the paint industry, entire painting lines are equipped with hoses from APT for the paint supply. Fluoropolymer tubing can also be found in the sector for consumer goods. The low surface energy allows an easy cleaning of the products and prevents, for example, fried egg sticking to the familiar Teflon ® frying pan. In auto- matic coffee machines, tubes are applied for the supply of hot water. Here, the special demands are: They must withstand constantly high temperatures while simulta- neously being pure – meaning without any kind of ad- ditives and plasticizers - so that they are physiologically safe. “Pureness is not just essential for food and nutri- tional products”, says Kipping. In the semiconductor in- dustry, so-called silicon wafers for the manufacturing of computer chips are exposed during the production pro- cess, developed and corroded. “The used chemicals pass through ultra-pure, resistant fluoropolymer tubing”, explains Kipping. A further exciting field of application for these hoses is the laboratory, analytics and biotech- nology. “During criminal investigations, a DNA analysis is commonly done with automatic equipment. Our tubes are also built into these devices. Thereby, each centime- ter of tubing must meet the highest quality standards. After all, no one should be sent to prison if innocent”, says Kipping. Due to the fact that tubes fromAPT are being used in vari- ous operating and security related areas, their production is subject to numerous standards. In the USA, for instance, drinking water and food compatibility is certified by the FDA (Food & Drug Administration). Furthermore, for medical technology, there are standards or regulations, such as ATEX, which regulate constructions in potentially explosive areas. For such application, tubes must be elec- trically conductive in order to avoid electrostatic charges. In addition, there are fire protection regulations, as well as fire protection classes, for example, for the use of tubes in airplanes. This ensures that in case a tube ignites through fire, it will melt eventually, but it will not burn because it is self-extinguishing due to its structure. Professional Quality Management For APT it is crucial to comply with standards to fulfil cus- tomer demands. Here the Quality Management plays a significant role. “Naturally, we are certified according to ISO 9001. All of our products are manufactured accord- ing to this standard and documented”, explains Kipping. To ensure the quality of the tubing and optimization of production processes, APT applies online measuring and control technology from SIKORA in their extrusion lines. In the past, the classical testing technology was a mere sampling inspection. Tubing sections were measured ran- domly regarding their inner diameter, outer diameter, wall thickness and ovality of the tube. The tube was run on the machine and after a certain time a sample was taken, which was then measured with the aid of a caliper rule and test pin. If the tube met the specifications, it was manufactured for the customer in the requested length. At the end of production, another sample was taken and measured. The quality of the complete tubing length was evaluated by the two samples. Inline X-ray measuring systems from SIKORA Over the years, the used measuring equipment was fur- ther developed and optimized. The sampling inspection was gradually replaced by the continuous inline quality control. “There are a number of methods for dimensional control”, says Kipping. “Since our foundation, we have chosen to use X-ray measuring technology from SIKORA. The decision was made on grounds of experience we gained by using other technologies and which showed us its limitation for the kind of measurements we needed. This was mainly regarding reproducibility of the data and their accuracy.” The X-ray measuring devices of the X-RAY 6000 PRO se- ries from SIKORA reliably and precisely measure the wall thickness, eccentricity, the inner and outer diameter and the ovality of up to three different material layers of a tube. With the inline measurement, the measuring val- ues are visualized on a big display of the corresponding processor system both numerically and graphically. The operator at the line can see at a glance if the values are within the defined tolerances. “The application of our X-ray measuring devices is very flexible. As with APT, it can be installed directly after the extruder - thus, before the cooling trough - or alternatively between two cooling troughs”, explains Peter Hügen, Area Sales Manager at SIKORA AG and first contact for APT. Right from the start, APT wanted to take a leading role regarding the quality of their products. We define our- selves mainly by the characteristic quality and this is a cru- cial aspect, as meanwhile, there are various suppliers of tubing from other countries. For this, a continuous quality control is necessary. With an inline-measurement of the