Combined Cutting & Drilling - Proven Concept - Large Savings
Elimination of one of the most expensive elements in production of large fabrications is now possible through application of high precision cutting and drilling technology available from Farley LaserLab. Conventional wisdom has it that for most large fabrications, the drilling and machining cycle must take place after the metal has been cut, formed and welded. In some areas such as plate girder manufacture for bridges and other large projects it is accepted that the plates can partially be prepared by, say, drilling just one end of the girder and leaving a green end, drilling the other end after the girder has been welded. If all the parts could be processed in the flat, before welding, then significant cost savings would accrue. Not only would the time needed for a job be a lot shorter, but the flexibility and design freedom would be much improved and the cost of equipment and labor involved would be substantially reduced.
The good news is that using the Farley LaserLab Atlas, prefabrication machining (PFM) can be carried out in almost all types of medium-to-heavy work in particular in the areas of equipment manufacture such as earth moving plant, bridge building and steel construction. Farley LaserLab has conceived its Atlas system in the knowledge that one of the main costs associated with heavy fabrication is in handling the product as it passes through the shop. Costs rise exponentially as the size of the fabrication increases. The key to minimizing handling is plainly to reduce the number of times the product has to move: hence a combined marking, drilling and cutting machine. An average of 60% of metal that is profiled needs subsequent drilling or marking so why are more fabricators not drilling the plate during the same set up as cutting it? Reluctance has primarily been down to a worry that the product will not align and match up properly during fabrication due to the distortions in the forming and welding processes.
But operating experience of the Atlas & Fabricator has now demonstrated that this need not be a problem. Over the past few years, Farley LaserLab has installed close to 40 Atlas and Fabricator systems (the Fabricator is a sister machine to the Atlas, used mainly on smaller projects) around the world, in steel service centres, bridge builders and OEMs. The machines are working on metal from as little as 5mm up to 120mm thick, and on plates as large as 3m wide by 30m in length. All these installations prove, in many differing ways, that the application of modern cutting, drilling, bending and welding techniques can radically change the way a product is manufactured.
ATLAS IN ACTION A typical application demonstrating the power of combined cutting and drilling is at bridge builder Fairfield Mabey in Chepstow, UK. The company installed an Atlas equipped with two 400amp plasma torches, two oxy-gas burners, a powder marker and 15kW drilling spindle coupled to a nine-station automatic tool changer. FM produces up to 30m-long (100ft) bridge girders. A typical web may have say 60 26mm diameter drilled holes, 20 marks to show the position of bridge stiffeners, and other identification marks for use in the final assembly and around 75m of actual cutting. The whole thing can be done in less than an hour, or around 20% of the previous times. Webs, flanges, stiffeners, and connector plates are all produced on the system, all in one setup all with just one operator. Apart from flexibility and accuracy advantages, other benefits include the ability to cut out and drill a whole kit of parts so that each stiffener can be custom-made to fit the girder, increasing the speed of subsequent robot welding operations. Operator hours per ton for plate girder manufacture are now around half European averages.
USA BRIDGE BUILDERS SEE THE BENEFIT AS WELL. Eastern Bridge, - Claremont NH, Industrial Steel Construction, Gary IN, and Universal Structural Portland OR, have all installed one or more Farley Plate working machines, combining the cutting and drilling. All report significant competitive advantages. Their costs are lowered, their throughput is increased and the quality is far better. On one job just completed by Eastern Bridge, the system drilled over 1 million holes, cut 95% of the material and marked out weldment positions. The job was completed in around 40% of the time it would have taken.
