A laser-based measurement system performs online diameter control and flaw detection of opaque or transparent extruded products. The Aeroel Extruline system from Marposs prevents the production of out-of-tolerance products by detecting and locating diameter flaws along the product’s entire length. It is suited for use with glass pipes, medical tubing, sections, electric cables, and similar products.

The non-contact technology enables measurement of moving products — hot or soft — without damage. Out-of-tolerance conditions trigger an alarm, helping to reduce scrap and rejects later in the process.

The diameter and ovality of stock from 0.05 mm (0.00196 in.) to 149 mm (5.86 in.) can be controlled either via a single- or dual-axis laser gauge, depending on the diameter range and type of product. Product vibration and movement do not affect the process. The gauge is installed just after the extruder head, eliminating any contact with the guiding roll and resulting in faster and more effective regulation, according to Marposs. Based in Auburn Hills, MI, the company is specialized in the development of measurement, inspection, and test technologies.

The accompanying Extruline software features guided menus for ease of use, even by untrained staff. Systems also include Glass Logic, high-performance software developed by Aeroel that provides reliable gauging of transparent products such as glass pipes and medical tubing. The software is pre-programmed at the factory to allow immediate use of basic functions.

In addition to three single-axis Extruline.X models, two double-axis Extruline.XY models are available. Depending on the system, repeatability falls within ±1 and 3.5 µm.

By connecting a printer to the CE-200 panel, users can generate a complete statistical report, including flaws detected along the product's length. The panel also features Ethernet or Rs232 interface to connect a remote computer that can be used to download the measured data or to program the system.

Software automatically corrects extruder if product deviates from pre-set limits.

The Extruline systems use an Xactum laser gauge installed at the exit of the extruder, which measures the outside diameter of the product. The non-contact operating principle enables through-feed inspection without having to stop or slow down the product, as its vibration and movement do not affect gauging accuracy.

The measured average diameter is continuously compared with the nominal value pre-set by the operator. If the product size deviates from the pre-set limits, the software automatically corrects the extruder so that the product remains within the desired tolerance limits. The measured data are displayed on the screen of a CE-200 operator interface panel, which is also used to program the system. All measurements are recorded and processed to get a complete statistical report, which can be printed immediately. Any sudden change in the product diameter is detected as a flaw, and the position of each flaw along the product length is stored in the system’s memory in order to print a flaw location report for each spool.