METHOD FOR SELECTING PARAMETERS OF APPARATUS FOR GAS-FLAME WELDING AND CUTTING OF METALS Russian patent published in 2003 - IPC

FIELD: welding processes and equipment, possibly gas welding or cutting at selecting parameters of ducts for feeding fuel mixture and speed of feeding it. SUBSTANCE: method comprises steps of selecting diameters of ducts and speed of feeding fuel mixture with use of diagram of stable burning of flame consisting of groups of characteristics of duct diameters and speed values corresponding to them; drawing said diagram on coordinate plane of speeds and diameters of ducts for feeding fuel mixture. Said plane contains main diagonal forming first group of diagram equal to 1.62 of wave-half length of flame front at stable burning (used as unit value) and inclined by angle of 36 deg relative to axis of diameters; initial tetragon, mean and small tetragons, right triangle and two separated by diagonal similar triangles. Contour of initial tetragon has two sides being projections of main diagonal respectively on axis of diameters and on axis of speeds. Third and forth sides of said tetragon are arranged symmetrically relative to above mentioned first and second sides around main diagonal. Mean and small tetragons are similar to initial one, and they are drawn by separation of main diagonal with ratio 2 : 1 and passing through point of separation of lines normal relative to sides of initial tetragon. Right triangle is drawn by passing outside initial tetragon through upper point of main diagonal perpendicular to said point until it crosses axes with extracted rectangular zone restricted by perpendiculars passed from upper point of main diagonal to its legs. Two similar triangles separated by diagonal are drawn inside right triangle with extracted rectangular zones similar to extracted zone of right triangle. Pore size of flame extinguishers is determined in addition according to diameters of characteristic of diagram of small tetragon reduced by 10 times. Diameters of ducts and speeds of feeding fuel mixture selected according to diagram of stable arc burning provide operation of apparatuses for gas-flame welding and cutting without fire-hazard condition, flame burns into atmosphere and reverse flame hits into duct. EFFECT: enhanced accuracy and stability of selected parameters. 2 cl, 3 dwg