PIPE-LINING BALL PIG

PURPOSE: To obtain a pipe-lining ball pig that can smoothly run surely along an irregular shape of an inner surface of a pipe to correctly and surely form a film of a lining resin with a uniform thickness. CONSTITUTION: When a ball pig 1 is inserted in a pipe to be lined 2, an elastic sheathing part 1b is slightly collapsed to be elastically pressed against the inner surface of the pipe 2. By applying a pressure into the pipe from the rear side in the forward direction of the ball pig, the ball pig 1 is moved in the pipe 2. A part of a loaded lining resin 3 is applied to the inner surface of the pipe 2. A lining film 3a is formed on the inner surface of the pipe 2 after the passage of the ball pig 1. If the ball pig 1 runs on the irregular inner surface of the pipe 2. such as a projected part in a welded part and an elbow, the ball pig, esp the elastic sheathing part 1b, is deformed along the irregular surface shape to pass through in contact with the inner surface of the pipe 2 at a fixed pressing force. Thus, the lining film 3a can be formed with a fixed thickness.