US Patent 9453389 Fluid injection device

A fluid injection device (18) for controlling injection of fluid into an oil-carrying tube in an oil well includes an inlet (20) for receiving the fluid; an outlet (28) for supplying the fluid for injection into the oil-carrying tube; an inlet valve (22) in a fluid path between the inlet and the outlet; an actuator (24) for opening and closing the valve; and a connector (36) for coupling the inlet to a fluid supply tube (32) extending between the device and a source of the fluid above the ground. A method of controlling injection of fluid using such a device is also provided.