The utility model discloses a bridge type is prevented with one heart returning and is told water injection mandrel belongs to the oilfield machine field. This water injection mandrel is including top connection, connection urceolus, bridge type body and the lower clutch connected in order. Be provided with vertical through -hole that communicates with the lower clutch and the radial hole who is linked together with bridge type body inner chamber on the bridge type body lateral wall. Bridge type body upper portion is provided with the guide cylinder for advance line location to the measure and regulate appearance. Be provided with fixed water mouth in the bridge type body inner chamber, the last delivery port that communicates with radial hole that is provided with of fixed water mouth. The activity water injection well choke passes through screw thread kind of drive and sets up in the guide cylinder, and the activity water injection well choke reciprocates with the flow surface who changes the delivery port long -pendingly. Small frictional resistance, be provided with the disk seat hole with the delivery port intercommunication on the disk seat. Press the apopore that is provided with on the cap with disk seat hole intercommunication. Be provided with compression spring in pressing the cap, compression spring one end is connected with ball sealer. This water injection mandrel has to prevent returning tells stifled, the measure and regulate accurately of function, difficult card.