Today’s automated systems—known as multisystem integration, or MSI— position workpieces using electric motors, inverters, and encoders. Monitoring the position of each piece, the MSI combines multiple machines into one production line. Once the production requirement is created and material is loaded, an MSI operates without manual input.
For example, material moves from a shot blasting machine to a drill machine, a layout marking machine, a sawing machine, and finally a plasma and oxyfuel robotic structural cutting system. All machines are mechanically connected to each other by roller conveyors and cross transports.
The production process starts at the detailing office where the project is created in a 3-D CAD system. Each product is broken down into a DSTV file that is then imported into the machine’s software. After this step, nested files are generated in a DSTV+ format, which is then uploaded to the master control of one of the machines. The product is then distributed from the master to all machines in the production line. Because every machine is connected to the master, each one always has the most up-to-date production data available.
Today the operator simply selects the loaded profiles on the control panel and starts the process. Data then is updated automatically at the production office and at every machine. The material handling system has built-in buffers so the production line knows the order in which the beams go through and which processes are required on each piece.
Cross transports with photocells detect the profiles and position them at the correct distance apart for the shot blasting of multiple pieces in one pass. Immediately after processing, transfer mechanisms move the beams to the next operation. Encoders and sensors in the roller conveyor register the exact position of the batch. When the sensor on the infeed control is passed, a new batch of beams is transported onto the infeed conveyor. The new batch holds position until the first bundle passes the outfeed sensor. The height of the beams is monitored to ensure the dimensions comply with the data in the software, and the height of the brush and blowoff unit is adjusted to remove any blast media from the web area before the beam moves to the next operation.
Cross transports between two machines function as a buffer to equalize differences in production speed. Beams on the cross transports are automatically repositioned to create enough space for the next bundle of beams. The software knows the beam positions and dimensions to ensure all operations connect seamlessly to each other—and all of this is followed in real time by the production office.
Mechanical drag-dogs move beams rapidly over the cross transports to minimize transfer time between machines. Before the beam crosses the infeed roller conveyor, the feed slows as it approaches the datum line to prevent damage.
A servo-driven feeder truck moves the beam, and at the same moment, the roller conveyor moves the beam toward the servo-driven feeder truck. This also reduces the transfer time. The beam is then processed while the next beam is transferred close to the infeed roller conveyor.
Short pieces (less than 47 in. long, for example) are removed and pushed sideways into a bin by a short product removal system. Leading and trailing edge trim cuts are removed and deposited in the scrap bin with no manual intervention. Finally, the long pieces are transported to the outfeed cross transports and are removed.