Equivalent laminar cooling method

The invention provides an equivalent laminar cooling method which comprises the step of: figuring out a diameter of each water outlet pipe of laminar cooling to ensure that the diameter of the water outlet pipe in the transverse width direction is gradually reduced from the center to two sides and the laminar cooling strength is distributed sinusoidally along the transverse width direction of strip steel and the laminar cooling capacity is gradually enhanced from two sides to the center of the strip steel, thus the cooling speed of the strip steel in the transverse length direction tends to be consistent and balance, the transverse performances of the strip steel subjected to laminar cooling are uniform and consistent, therefore, the stress concentration caused by temperature drop on the edge of the strip steel is eliminated, the defect of edge waves or buckling of the strip steel is avoided and reduced, and the surface quality and the internal quality of the strip steel are improved.