When Canadian energy services company Packers Plus needed to read challenging dot peened codes on a variety of parts, they specified Cognex® DataMan® handheld ID readers. The company’s StackFRAC® system consists of many parts, each marked with a unique 2D Data Matrix code that enables traceability throughout its useful life.
Traceability delivers two important benefits for Packers Plus. First, it reduces rework costs by providing better manufacturing process control and ensuring that the right parts are used at every stage of production. Second, it enables Packers Plus to quickly retrieve information on 100% of the parts in every system that has been shipped out their door, including production history and quality control information.
In the past, Packers Plus manually recorded information such as lot numbers, heat numbers, quality control measurements and other information in a spreadsheet. “This was a very time-consuming manual process that took approximately four hours for each product, so we only did it when necessary,” said Marlon Leggott, Director of Manufacturing for Packers Plus. “Another problem with the manual process is that it is susceptible to mistakes, such as data entry errors.”
Selecting marking and reading tools
Packers Plus considered a number of different options for improving traceability when it installed its new ERP system. Kurtis Weber of iTech Tool Technology helped Packers Plus design the traceability solution. “We looked at labels with standard line bar codes but determined they would have to come off during assembly, which would negate many of the advantages of serialization,” Weber said. “RFID tags don’t work well with various metal parts because of interference with reading and writing the tags. Laser marking overcomes all of these problems but laser marking machines begin at $50,000 and have to be enclosed -- which causes problems when used to mark large pieces -- and cannot easily be moved from place to place. We recommended a dot peen marking system because it is permanent, does not rely on fragile RF transmissions, costs only about $10,000 per machine, and is available in fixed or mobile models. The mobility allows us to easily move around the plant and successfully mark any size part in a variety of orientations.” With dot peen marking, a carbide or diamond-tipped stylus pneumatically or electromechanically strikes the material surface.
Packers Plus then faced the difficult challenge of reading the marked parts. The challenge arises from the fact that Packers Plus makes parts with curved surfaces and many different materials and coating combinations. Nearly any reader can be adjusted to provide perfect accuracy on a particular combination but Packers Plus wanted a reader that could deliver high levels of accuracy on any part. “We recommended Cognex DataMan handheld readers because they adjust the lighting to match the part and use the industry’s most advanced algorithm for picking out the 2D Data Matrix code from the background,” Weber said. “This is the only product I have seen that is capable of accurately reading the wide range of parts used by Packers Plus.”