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WELDER - CITS



           Too much preheating. The cut shows a rounded top edge caused by too much preheat. Excess preheating does
           not increase the cutting speed, it only wastes gases.  (Fig 5)

             Fig 5













           Poor quality bevel cut. The most common fault is gouging, caused by either excessive speed or inadequate
           preheat  flames. Another  fault  is  a  rounded  top  edge  caused  by  too  much  preheat,  indicating  excessive  gas
           consumption.  (Fig 6)
              Fig 6










           Slightly too fast a cutting speed. The drag lines on this cut incline backwards, but a drop cut’ is still attained.
           The top edge is good; the cut face is smooth and slag-free. This quality is satisfactory for most production work.
           (Fig 7)


             Fig 7







           Slightly too slow a cutting speed. The cut is of high quality although there is some surface roughness caused
           by the vertical drag line. The top edge is usually slightly beaded. This quality is generally acceptable, but faster
           speeds are more desirable because the labour cost for this cut is too high.  (Fig 8)

             Fig 8









           In a good cut, the edges are square, and the lines of cut are vertical. (Fig 9)

            Fig 9















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 CITS : C G & M - Welder - Lesson 4&5      CITS : C G & M - Welder - Lesson 4&5
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