Alkaline degreasing agent for cleaning cold rolling continuous annealing unit and low-cost manufacturing method thereof

The invention discloses an alkaline degreasing agent for a cleaning cold rolling continuous annealing unit and a low-cost manufacturing method thereof. The degreasing agent comprises the following components in percentage by weight: 25-35% of alkaline substances, 4-8% of scale and corrosion inhibitor, 3-6% of surface active agent, and the balance of water; the scale and corrosion inhibitor is formed by mixing sodium gluconate with polyepoxy succinate sodium according to a weight ratio of 1: 0.4-1.2; and the surface active agent is formed by mixing phenol phosphate ester solubilizer, alkylphenol polyoxyethylene and anionic polyacrylamide according to a weight ratio of 1: 0.2-0.4: 0.3-0.6. The use levels of the surface active agent and the scale and corrosion inhibitor in the alkaline degreasing agent are largely reduced; and the medicament cost and the transportation cost of the alkaline degreasing agent are largely reduced under the precondition of guaranteeing the cleaning effect.