| abstract |
(57) Abstract: In a pretreatment for coating, which is performed by immersing a metal molding in a liquid in a treatment tank, a more uniform and favorable treatment or a treatment for preventing adhesion of metal powder is performed. SOLUTION: The liquid in the treatment tank 1 is agitated by vibrating and stirring means 2 and 3 provided in the treatment tank 1, and the liquid or the metal molding substance within a range 10 in which the metal molding product is immersed. It is characterized in that the liquid in the vicinity of a horizontal plane is treated while being stirred so that the average acceleration a represented by the following formula becomes 8 cm / sec 2 or more. [Equation 1] (The units of X, Y, and Z are cm / sec 2 , and these values are the same as the flow velocity of the liquid in each of the three axes X, Y, and Z orthogonal to each other at the measurement location of the flow state of the liquid. It is a value obtained by averaging the accelerations of the flow velocity changes measured for 60 seconds.) |