To provide an in-pipe pump which has a shaft of a spiral band body for conveying high-viscosity substances inside a L-shaped pipe and causes no detention time of conveying high-viscosity substances such as cake, paste and slurry and besides is easy to wash and further is short in jointing portion's length and furthermore is located inside a pipe and moreover has a driving motor that is located inside the pipe and can be reduced in weight and size and then is suitable for transporting foods.

There is provided the in-pipe pump in which in pipe conveyance using the L-shaped pipe for conveying the high-viscosity substances through the pile, the shaft of a spiral band body is inserted, toward a conveying direction, into an inside of an L-shaped portion of the pipe in a contact-free state with the inside of the pipe and is rotated coaxially with the pipe by the driving motor and besides which is supported at one to three supporting points between a pimp shaft and the driving motor. The in-pipe pump has a size equal to a spiral band body's width approximated to a diameter of the pipe and is equipped with the spiral band body of 1.5 to 5 mm in thickness and of 300 to 500 mm in length.