Experiences With TP-CTL
Defiance Metal Products. This Defiance, Ohio-based company operates seven laser cutting machines and six CNC punching systems. Before it began using TP-CTL sheet and plate, a crash between a cutting head and bowed material could cost several thousand dollars in repairs, as well as lost production time. Such costly crashes prompted its decision to convert to TP-CTL material.
John Deere. This company's Dubuque, Iowa, plant had been using a large volume of TP-CTL hot-rolled strip mill sheet and plate since the mid-1980s, although in the early stages, temper-pass material was produced using coil-to-coil technology because TP-CTL systems had not yet integrated. After this integration, John Deere began specifying TP-CTL material whenever possible.
Why did John Deere switch to the more expensive TP-CTL? The main reason is that material arrives extremely flat and stays flat during the manufacturing process, according to Richard Courtade, senior engineering analyst, and Sandy Haupert, supply base manager. The company claims the increased costs of materials are offset by the benefits of TP-CTL.
For example, flat material allows extensive use of common-line laser cutting. Used in conjunction with sophisticated nesting, common-line cutting results in parts that do not require expensive secondary flattening operations. Using flat material also reduces robotic arc welding costs for the company because fixturing requirements are simpler.
The company says TP-CTL improves the surface finish of hot-rolled material. Because the surface is smoother with fewer imperfections, painting quality has improved without using surface finishing processes.
John Deere now purchases only TP-CTL strip mill sheet and plate where it is available. Currently this covers grade 50 material up to 12 mm thick.
Caterpillar. Also an early adopter of TP-CTL hot-rolled strip mill sheet and plate, Caterpillar says it uses this material mainly because of problems and subsequent costs associated with conventionally leveled material.
Dennis Kunka, project engineer-steel for Caterpillar, emphasizes the importance of setting up the TP-CTL processing line correctly so that stress is applied evenly to the material. He cites past instances when improperly processed material resulted in a flatness condition that was worse than if the material had not been temper-passed at all.
