Technical Description
The TOS VARNSDORF TOSTEC GRATA is a robust horizontal machining center designed for precise and highly productive machining of large, heavy workpieces. It features a 79" x 79" standard table size, expandable up to 98" x 118", with a maximum workpiece capacity of 55,100 lbs, supporting complex and heavy components. The spindle is horizontally oriented, with a CAT-50 taper (ISO-50 optional) capable of speeds up to 5,000 RPM, expandable to 20,000 RPM in optional configurations, and powered by a 50 HP motor rated for 30-minute duty cycles. This strengthening of spindle technology allows for high-performance milling and drilling operations.
The machine is equipped with an automatic tool changer (ATC) holding 40 tools standard, upgradable to 80, with a 14-second tool change time, enhancing productivity and reducing downtime. Its axis configuration includes three controlled linear axes (X: 197" travel, Y: 63", and Z: 59") with rapid traverse rates of 984 inches per minute, permitting efficient positioning and machining. Optional expansions allow up to seven axes, including rotary A (110°) and B (360°) axes for enhanced machining versatility.
Built for heavy-duty and flexible manufacturing, the GRATA unit incorporates an extensible ram with a 500 x 500 mm cross section, ensuring high rigidity and stability under multi-shift usage. The machine supports additional technological equipment such as rotary tables and clamping devices, adapting to diverse production needs from serial to single-piece machining. The system integrates advanced CNC controls (Heidenhain iTNC 530 or Siemens SINUMERIK 840D), enabling precise machining with incremental programming to 0.001 mm and automated tool and accessory management, offering a modular, scalable solution for complex, large-scale horizontal machining applications.