Hydraulic pressure welding seam leak-checking agent and preparation method thereof

The invention discloses a hydraulic pressure welding seam fast leak detection agent, which contains constituents of (mass percent): ethanol of 65-70%, poly(vinyl butyral) of 0.13-0.18%, light magnesium oxide of 28.5-33.5%, thymol blue of 0.10-0.15%, and anti-precipitation agent of 1.22-1.5%. Preparation method for the leak detection agent includes steps: adding ethanol into a intermittent sand mill, actuating the sand mill, firstly adding poly(vinyl butyral), and then adding light magnesium oxide, thymol blue and anti-precipitation agent, grinding the mixer until no particle, and obtaining the leak detection agent. Advantages of the invention are: drying of coating is fast, adhesive force is good, color contrast is obvious, color change of water seepage in welding seam and outside spitting water can be differentiated, and estimation effect is fast and exact.