Wall bore electrical generator

• US 4,532,614 A
• Filed: 06/01/1981
• Issued: 07/30/1985
• Est. Priority Date: 06/01/1981
• Status: Expired due to Fees

• Current Assignee: James M. Peppers
• Original Assignee: James M. Peppers
• Inventors: Peppers, James M.
• Primary Examiner(s): Moskowitz, Nelson
• Assistant Examiner(s): Lobo, Ian J.
• Application Number:
  US06/269,427
• Time in Patent Office: 1,520 Days
• Field of Search: 367/82, 367/83, 367/81, 367/84, 367/911, 340/853, 340/854, 340/856, 324/369, 324/373, 324/356, 455/40, 175/48, 175/50
• US Class Current: 367/81
• CPC Class Codes: E21B 41/0085 Adaptations of electric power generating means for use in boreholes
• CPC Class Codes: G01V 11/002 Details, e.g. power supply systems for logging instruments, transmitting or recording data, specially adapted for well logging, also if the prospecting method is irrelevant means for transmitting well survey signals E21B47/12; signal transmission systems in general G08C; transmission in general H04B

Abstract

Discloses a well bore electrical generator for a subsurface measuring system incorporating a rotary liquid seal protection system adapted to be actuated by flow of drilling mud through the drill pipe. System includes a sealed housing defining a first chamber separated from a second chamber with the chambers being filled with a sealing liquid. A rotatable shaft driven by an impeller extends from outside the housing into the first chamber through a rotary seal connected to establish a liquid seal between the housing and the shaft. Means are provided for maintaining the fluid pressure of the sealing liquid within the chambers to be equal to the fluid pressure of the drilling mud outside the housing. A rotatable pump connected to the shaft is adapted to pump the sealing liquid from the second chamber into the first chamber. A liquid pressure regulator is connected to regulate a return flow of sealing liquid from the first chamber to the second chamber and control the fluid pressure of the sealing liquid applied to the rotary seal from inside the first chamber to be greater than the fluid pressure applied to the rotary seal by the drilling mud from outside the housing.

Claims

1. In combination with measuring while drilling electrical power generator, a rotary liquid seal protection means adapted to be actuated by the flow of drilling mud through a drill string, comprising:

(a) a sealed housing defining a first chamber separated from a second chamber;

(b) said chambers being filled with a sealing liquid;

(c) a rotatable shaft extending from outside said housing into said first chamber through a rotary seal means connected to establish a liquid seal between said housing and said shaft;

(d) pressure equaliziang means for maintaining the fluid pressure of said sealing liquid within said housing and said chambers to be equal to the fluid pressure of the drilling mud outside said housing;

(e) a rotatable pump means connected to pump said sealing liquid from said second chamber into said first chamber when rotated by said shaft;

(f) a liquid pressure regulating means connected to regulate a return flow of sealing liquid from said first chamber to said second chamber and to control the fluid pressure of the sealing liquid applied to said rotary seal means from within said first chamber to be greater than the fluid pressure of the drilling mud applied to said rotary seal means from outside said housing; and

(g) an impeller means mounted to said shaft exterior of said housing and adapted to rotate said shaft when rotated by the flow of said drilling mud past said housing.

2. The combination of claim 1 wherein said pressure regulating means comprises a selectively biased poppet valve means.

3. The combination of claim 1 wherein said rotary seal means is of the face type.

4. The combination of claim 1 wherein an electrical generator is mounted within said first chamber and adapted to be rotatably driven by said shaft.

5. The combination of claim 1 wherein said pressure equaliziang means comprises spring biased check valve means communicating between said chambers.

6. The combination of claim 5 wherein said pressure compensation means includes a floating piston disposed in said second chamber between said drilling mud and said sealing liquid.

7. The combination of claim 1 wherein said pump means comprises a gear type pump.

8. An impeller driven electrical power generator in combination with a rotary liquid seal protection means adapted to be actuated by the flow of drilling mud through a drill string, comprising:

(a) a sealed housing defining a first chamber separated from a second chamber;

(b) said chambers being filled with a sealing liquid;

(c) a rotatable shaft extending from outside said housing into said first chamber through a rotary seal means connected to establish a liquid seal between said housing and said shaft;

(d) said electrical power generator means being mounted within said housing and connected to be rotatably driven by said shaft;

(e) pressure equaliziang means for maintaining the fluid pressure of said sealing liquid within said housing and said chambers to be equal to the fluid pressure of the drilling mud outside said housing;

(f) a rotatable pump means connected to pump said sealing liquid from said second chamber into said first chamber when rotated by said shaft;

(g) a selectively biased liquid pressure regulating means connected to regulate a return flow of sealing liquid from said first chamber into said second chamber and to control the fluid pressure of the sealing liquid applied to said rotary seal means from within said first chamber to be greater than the fluid pressure of the drilling mud applied to said rotary seal means from outside said housing; and

(h) an impeller means mounted to said shaft exterior of said housing and adapted to rotate said shaft when rotated by the flow of said drilling mud past said housing.

9. In combination with an impeller driven electrical power generator adapted to be actuated by the flow of drilling mud through a drill string, a rotary seal protection means comprising:

(a) a sealed housing defining a first chamber separated from a second chamber;

(b) said chambers being filled with a sealing liquid;

(c) a rotatable shaft extending from outside said housing into said first chamber through a rotary seal means connected to establish a liquid seal between said housing and said shaft;

(d) pressure equalizing means for maintaining the fluid pressure of said sealing liquid within said housing and said chambers to be equal to the fluid pressure of the drilling mud outside said housing;

(e) a rotatable pump means connected to pump said sealing liquid from said second chamber into said first chamber when rotated by said shaft;

(f) a selectively biased liquid pressure regulating valve means connected to regulate a return flow of sealing liquid from said first chamber into said second chamber and to control the fluid pressure of the sealing liquid applied to said rotary seal means from within said first chamber to be greater than the fluid pressure of the drilling mud applied to said rotary seal means from outside said housing; and

(g) an impellar means mounted to said shaft exterior of said housing and adapted to rotate said shaft when rotated by the flow of said drilling mud past said housing.

10. The combination of claim 9 wherein an electrical generator is mounted within said housing and adapted to be rotatably driven by said shaft.

11. The combination of claim 9 wherein said pressure regulating means comprises a selectively biased poppet valve means.

12. The combination of claim 9 wherein said rotary seal means is of the face type.