فرزاد تیمناک
بیژن نیک سرشت
علی شهبری

Cast iron pipes that used for water and sewa7e transfom1ation is produced by centrifugal casting machines. . The steel permanent mould of these machines are cracked and wear out after producing a few thousands of pipes and must be repaired before reusing. . The repairing and, recovery of these permanent mould is done by specially designed submerged arc welding machines. In this investigation , initially the eftectsof different welding factors such as welding current, polarity, voltage, travel speed , electrode diameter, thickness of flux co\'cr on shafC of weld bead and weld quality is searched . ' AJso the eOCct of above mentioned 18ctors on melting rate. weld dilution and heat dissipating to base metal's is dicusscd.finally . rotational speed of mould, feed speed of electrode wire and linear speed of wclding head for achievement of weld integrity. its quality and penetration is calculated