Automated Gantry Shuttle System
Standard Forged Products is one of the largest manufacturers of rail road axles, wheels, and rail cars in the world. In 2013, EURO Machinery Specialists received the order to completely remanufacture what is referred to as the "3 Stage" axle line for the McKees Rocks, PA plant. The scope of this project entailed both a complete mechanical and electrical remanufacture of the entire machining system. SIEMENS 840D sl controls are used to provide the new platform for this upgrade as well as SIEMENS AC servo motors and drives, new electrical cabinets and power hardware. A brand new overhead gantry parts loader for shuttling of axles was engineered & designed to transfer axles at each machining position and the load/unload stations.
This 3 Stage machining line is one of the most crucial components to SFP’s railroad axle production facility and consists of three heavy duty horizontal turning machines capable of producing a finished "turned" axle – approximately every four minutes – starting from a raw forging. The 3 Stage is integrated with an overhead automated gantry system designed to shuttle axles simultaneously to the various stages of the machining system - from roughing, semi-finish, and finish horizontal lathes and to the load/unload stations. The application is extremely impressive considering the aggressive depth of cuts and overall chip removal rates as well as the 24/7/365 high production environment. Large spindle motors and drives were sized to accommodate the demanding task. For example, the first Stage of the machining line referred to as the "rougher" required two 150 HP SIEMENS AC spindle motors synchronized for each headstock. These drives provide ample power and torque to handle the incredible depth of cuts as well as the variability in axle roundness. It is common to find a raw axle out of round by approximately ½" to ¾", and therefore an optional SIEMENS feature "Adaptive Control" was implemented which automatically adjusts axes feed rates while monitoring servo load during heavy cutting situations in order to prevent tool breakage or potential harm to the machine. In this case, if the controller monitors servo loads exceeding a normal range, feed rates are then adjusted automatically.