SYSTEM, METHOD AND APPARATUS FOR CONTROLING FLUID FLOW THROUGH DRILL STRING

摘要

A device for limiting the flow of drilling fluid through a section of drill string includes a body with a hole in the periphery. Flow enters the device through one axial end, at least a portion of the flow exits through the other axial end. Some of the fluid flow can be diverted through the peripheral hole. A spring-biased axial piston may have an approximately constant force throughout its range of travel. The piston moves axially in response to the changing fluid flow rate to enable a constant amount of flow exiting the axial end of the tool to be achieved while diverting away excess flow through the side.

主权项

1. An apparatus, comprising:
a housing having an axis, a radial wall with a bore extending axially through the radial wall, and an aperture formed in the radial wall, the aperture being in fluid communication with the bore; a component located inside the housing and having an orifice configured to permit axial fluid flow through the housing; a bias device located in the housing and configured to bias the component to a closed position; and the component is movable from the closed position wherein the component is configured to substantially close the aperture in the housing to substantially block fluid flow therethrough when downhole axial fluid flow through the orifice is insufficient to overcome a bias of the bias device, and an open position wherein the component is configured to permit fluid flow through the aperture when downhole axial fluid flow through the orifice is sufficient to overcome the bias of the bias device and move the component.