Method of control of arc welding process


(57) Abstract:

Method of control of arc welding process, which determines the calculated values of the electric parameters of the welding process and geometrical parameters of the weld pool, compare them with the current values, which are continuously measured during welding and, depending on their deviations produce the regulation of the welding process, wherein the pre-produce the welding samples of different lengths of the same material and the same thickness, and joint connection of the product, determine the maximum change in deflection width of the welding gap before welding arc from the set by changing the length of the welded sample while maintaining the quality of welding

B = max((Zi-Zi+1)(i-i+1)),

where is the maximum change in the magnitude of the welding gap, mm/m;

Zi- the maximum deviation of the welding gap, mm, from the given value, when welding sample lengthim;

Zi+1- the maximum deviation of the welding gap, mm, from the given value, when welding sample lengthi+1, m, then when welding butt joints products determine the score = (Zo- Zt)/t,

where Bt- the current deviation of the welding gap, mm/m;

Zo- the set value of the welding gap, mm;

Zt- the current value of the welding gap, mm;

t- the current length of the weld, m,

and if Btmore change In the calculated value of the welding current

IRK= Ip- k(Bt-B),

where IRK- calculated reference value of the welding current with a correction for changes of the welding gap along the length of the weld;

Ip- calculated reference value of welding current.

k is an empirical coefficient equal to 4.8.


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