TPT November 2012

Technology News

Industrial Ethernet in geometric control of cast iron pipes

bending press, which serves as a measuring station. The measuring device consists of a linear table with precision drive, which adjusts the spacing of the two scanners, depending on the pipe diameter to be measured. The linear table itself is attached to a robotic arm and is guided by the latter into the pipe end to be measured. The pipe diameter is determined prior to the insertion of the measuring device in the pipe with an M10L laser sensor, allowing the pipe inner diameter and the geometric centre of the pipe to be determined. During the measuring procedure, the linear table is rotated 180°. Both scanners detect, during a measuring period of about two seconds, the ovality of the pipe as well as the geometry of the circumferential connection profile. The data collected by the scanners is sent in real time via Ethernet to the evaluation PC. The MEL software calculates the deviations from the nominal dimension and also the resultant bending parameters. The software then controls the rotation of the pipe into the correct bending position. The bending machine is addressed with the necessary parameters, and the bending process follows. After bending, a control measurement is made in order to record the success of the bend. Different pipe diameters as well as differences in the flange and connection profiles require a flexible measuring system to be used. The system solution used is able to detect pipes with diameters ranging from 350 to

IN order to check the ovality and the flange geometry of cast iron pipes, MEL has implemented a system solution with M2-iLAN laser scanners. The system is able to achieve an accuracy of 0.1mm. The flexible Ethernet cable, moved by the robotic arm, has a great influence on achieving this precision. The manufacturing of steel pipes is usually subject to a thermal process. Duktus manufactures pipes complete with flange and connection profile using centrifugal casting. Upon the cooling of a pipe, different material distortion often develops, giving the pipe an oval shape. So that the pipe meets the high quality requirements, it must be measured accurately after cooling and, if necessary, be mechanically reworked. In addition to ovality, the flange and the connection profile are also checked at the pipe ends for errors and chips. Until now, the measurement has been made with a manually operated contact measuring system at individual points. The subsequent bending process has been manually initiated and controlled. Duktus now uses a system based on two MEL Mikroelektronik GmbH M2- iLAN scanners. The system solution has been integrated into the automated manufacturing process and controls the entire measuring and bending process fully automatically with its own logic. The operator’s long-standing experience, along with its empirical findings, is incorporated. The pipes to be measured are moved by a PLC-controlled transport system into the holding device of the hydraulic

MEL M2-iLAN laser scanners

1,100mm. Different flange profiles can be stored in the software. The operator can therefore customise the system to changes in the production line. The MEL software arranges and coordinates the individual components involved in the process with one another. Initiated by the material control, which moves the pipe to be measured into the holding device of the bending machine, the MEL software controls the entire measuring and bending process. This is possible since the acquisition of the measured values and their evaluation both take place within the software.

MEL Mikroelektronik GmbH – Germany Email: b.rohloff@melsensor.de Website: www.melsensor.de

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N ovember 2012