Making ends meet
For Patrik Reichmuth, project engineer at AVM Engineering, the objectives for the IR-110 pipe joining machine were clear. "More and more processes are being automated because it helps improve quality and productivity as well as relieving workers," he says. "Collection of operating data is also taking on higher priority, because it enables traceability and analysis." These trends certainly apply Georg Fischer's pipe joining machine. "Automating the process ensures consistent fusion quality and offers improved operator guidance with instruction videos. Recorded production data makes the joining process traceable and can be used to verify quality."
Size was also a top concern for Reichmuth, since everything would need to fit in the interior of the machine. To achieve the compact dimensions, he selected an integrated safety solution, a Panel PC with an ARwin soft PLC and an X20 controller. The servo motors are controlled by a compact, versatile ACOPOSmicro. B&R's X20 is more than just a remote I/O system; it is also a complete, integrated control solution with a very small cabinet footprint.
Ease of handling
User-friendliness was high on the list of design priorities. The goal was to make safe, correct operation of the machine as intuitive as possible. To achieve this, the touch-screen user interface provides instructions in the form of videos and animations. As one of the first to implement B&R's new Panel PC 2100, AVM benefited from the considerable increase in computing power.
The IR-110 guides users intuitively through the process of joining together plastic pipes using a process of infrared butt fusion. The most important module is the pipe sled on top of the machine, where the pipe to be joined is clamped in place. A B&R servo motor moves this sled horizontally along a threaded rod to bring the pipe into position for the butt fusion process. The forces applied are measured by a load cell, and used to regulate the amount of force by adjusting the torque.
The module sled is used for tool selection and carries tool modules horizontally with the help of a B&R servo motor. Another servo motor raises the edge facer and positions it between the two pipes. A DC motor rotates the blade to prepare the ends of the two pipe sections. The cutting speed, peak force and positioning are all defined by a recipe. The beveler can be moved to various positions for cleaning.
The heating element is also moved vertically between the two pipes. Without contact, but at a clearly defined distance, the ends of the pipes are heated to melt the material. It is important that the heating element can be lowered out of the way at any time to allow a quick transition when it is time to press the heated pipes together. The material must also be prevented from overheating, which could otherwise create noxious fumes.
Fischer is very pleased with the increased level of automation and intuitive user interface. Among the many benefits of the new solution is that the automated production steps allow the operator to have multiple machines running simultaneously rather than having to remain standing at a single machine from start to finish. They can also create new types of fusion joints that previously were not possible. With the predecessor model, notes Reichmuth, the user had to choose the correct tool, manually position it between the pipes and exert considerable effort to trim the ends. There was also much less data collection and quality control.
The machine's modular design allows it to accommodate a variety of tool modules. Reichmuth is already considering adding an inspection module that uses a camera to examine the fusion bead and calculate the precise quality of the finished joint. "We also have plans to build variants of the machine in different sizes," he says, "but at the moment we're working on upgrades to the HMI application, such as the ability for operators to log on using barcodes."