An Injector head is the primary component of a capillary injection system. During installation, the operator routes capillary tubing from the spooler to the top of the injector and passes it through the sheave alignment wheel. A series of grooved wheels aid alignment and pre-straighten the tubing prior to entering the gripper blocks which are integrated into the drive chains. The dual chain configuration utilizes two opposing chains with integrated gripper blocks to push (inject) or pull tubing via hydraulic cylinder traction system.