The invention discloses a speed integration device used for shield tunneling machines. The device is of an integral structure and comprises a device body. A first flow channel port, a second flow channel port, a third flow channel port and a fourth flow channel port are formed in the device main body. The first flow channel port communicates with the second flow channel port through control of a mandrel, the third flow channel port selectively communicates with the second flow channel port through a shifting plate and a floating body, and the demands for different flows of flow channels can bemet. The axial cross section of the end of the mandrel is approximately in a parabolic shape, more specifically, the axial part of the end of the mandrel is in a quadric-curve shape, and the part ofthe top end of the end is arranged in a semicircular shape. The flow adjusting device provided by the invention is compact in structure, accurate to adjust, capable of achieving linear throttling andmeeting various flow demands and is used for mechanical hydraulic systems such as the shield tunneling machines.