The mechanical properties of the cast iron parts of the water ring vacuum pump are relatively poor, and cracks are prone to occur due to impact, uneven force or freeze cracking. Cracks must be found before repairing

part and size. For insignificant crack defects, the simple method of kerosene test is often used to judge.

First, apply an aqueous solution of chalk powder to one side of the suspicious area, and when it dries, apply kerosene to the other side. Due to the ability of kerosene to penetrate fine crevices, when there are microscopic

When there are small and inconspicuous cracks, kerosene can penetrate through, infiltrate the white hard powder and make it discolored. Therefore, depending on whether the chalk is discolored, and the shape and size of the discoloration,

To judge whether there is a defect, as well as the shape and location of the defect.

Cracks in parts can be repaired by general welding methods and epoxy resin bonding cracks.