Resources Contact Us Home
Rotary earth boring tool

Image Number 4 for United States Patent #4406332.

The present invention provides a nonstalling system for advancing a boring tool in situations where the inclination of the bore hole with respect to the vertical is such that the force of gravity does not provide effective forward thrust. A hydraulically powered marine screw propeller adjacent the boring tool provides the necessary thrust for the drilling operation. Pressurized drilling fluid provides the required hydraulic energy. The characteristics of the marine screw propeller are such that it provides maximum thrust at maximum rotative speed but should the tool stall the forward thrust drops to zero preventing stalling.

  Recently Added Patents
Shape based similarity of continuous wave doppler images
Rupture resistant system
Potential separation for filling level radar
Methods and systems for managing print device supplies using cloud administration system configured for chemical signature tracking
Vehicle having power supply apparatus
Method and system for shared high speed cache in SAS switches
  Randomly Featured Patents
(Oxo)sulfonium complex, polymerizable composition containing the complex, and method of polymerizing the composition
Window cleaning appliance
Image displaying apparatus
Propulsion system for a semi-buoyant vehicle with an aerodynamic
Compositions for tobacco sucker growth control
Coated articles having enhanced reversible thermal properties and exhibiting improved flexibility, softness, air permeability, or water vapor transport properties
Suppression of respirable dust with foam
Downhole tools with solid-state neutron monitors
Pneumatic radial tires