Guyson Corp.'s Model RB-72 is an extended-height robotic blast machine with a 72 × 72-inch work envelope and pressure-blast media delivery for precision surface preparation applications in the aerospace industry, including composite structures.
The Model RB-72 uses a Fanuc M-20iA robot as a blast nozzle manipulator. The hollow arm of this 6-axis robot allows the blast hose to be routed directly through it. The grit-blasting machine’s 36-inch diameter powered turntable has a 1,000-pound weight capacity, and the servomotor-driven table is controlled as a seventh axis of coordinated robotic motion to exactly orient components that are fixtured on it. The table is supplied with T-slots to facilitate positioning of interchangeable fixtures.
The blast system’s designer and manufacturer claims the robotic grit-blast machine is capable of constantly and accurately maintaining the correct nozzle angle, stand-off distance and surface speed as it follows the contours of complex-shaped components throughout the programmed blasting cycle, thus enabling the highest level of consistency in production of a specific roughness on target surfaces, both from one area of the component to another and from part to part.
A slot in the top of the blast cabinet sealed by overlapping rubber flaps allows safe and convenient loading and unloading of heavy components using the half-ton capacity roof-mounted jib crane. A railed platform and stairs, as well as cabinet floor grating, are provided to allow operator access to the blast enclosure. Alternatively, the Model RB-72 can be supplied with a track extension and powered transfer cart to permit unrestricted overhead access. The robotic grit-blast machine is supplied with a dual-chambered, continuous-blasting pressure vessel that holds 8 cubic feet of media and a grit storage hopper that holds a reserve supply of 3 cubic feet. When electronic probes in the pressure pot detect a low media level, fresh blasting grit is automatically added to the system. Sensing and automatic control of blast pressure and verification of grit flow is also available, as are detection and fault indication of loss of air supply pressure, inadequate reclaim air flow and full dust drum.
Configuration of the robot controller and blast system controls insure the integrity of the robotic blasting process is based on the preferences of the customer. The grit-blast machine’s programmable logic controller (PLC) normally supervises all functions of the blast cabinet and the media reclamation and delivery system. The robotic arm and the robot controller can be slave to the PLC and strictly dedicated to the motion of the blast nozzle or part that is associated with the process recipe for each component. The robot controller does have the capacity to process limited inputs and outputs for control of a simple blast process without reliance on a PLC. In some cases, the robot controller and PLC can be integrated to work together with the PLC slave to the robot controller. Prospective users of automated or robotic blasting equipment are strongly encouraged to submit sample components for free laboratory testing and application engineering evaluation at the blast machine builder's factory in northeastern New York State.