Selfcoupled Equations for the Field Correlators

New nonlinear equations for field correlators in the large $N_c$ gluodynamics are derived. Nonperturbative confining correlators are shown to satisfy a system of nonlinear scale-invariant equations. Keeping only the simplest, bilocal correlators one can find the exponential large distance behaviour for both independent correlators $D$ and $D_1$ and express coefficients in the exponentials – the gluonic correlation length $T_g$ – through the string tension. Numerically these results are in agreement with lattice data.