High efficiency drill pipe

Abstract

A drill pipe 10 comprises an elongate pipe section 12 having a substantially uniform pipe outer diameter 18 and a substantially uniform pipe inner diameter 20 . A pin tool joint 14 is welded at one end to the pipe section, and a box tool joint 16 is welded to the other end of the pipe section. Each of the pin and box tool joints includes a thread for mating engagement and preferably first and second shoulders. The drill pipe has a ratio, R, which takes into consideration the pipe inner diameter, P ID , the pipe outer diameter, P OD , the tool joint inner diameter, TJ ID , and the tool joint outer diameter, TJ OD . This ratio may be expressed as: R = ( P ID + TJ ID ) ( TJ OD - P OD ) . According to the present invention, this ratio is greater than 8.0, and is preferably from 8.1 to 8.5, thereby providing a drill pipe with desired strength and fluid flow capabilities.

1. A drill pipe with enhanced strength and fluid flow capability, the drill pipe comprising:
 an elongate pipe section having a central axis, a substantially uniform pipe outer diameter, P OD , of from  5   3 / 4  inches to  6  inches along its axial length, and a substantially uniform pipe inner diameter, P ID , along its axial length;  
 a pin tool joint at an axial end of the pipe section, the pin tool joint having external pin threads and a pin shoulder;  
 a box tool joint at an axial end of the pipe section opposing the pin tool joint, the box tool joint having internal box threads for mating engagement with the external pin threads of a mating drill pipe and a box shoulder for engagement with the pin shoulder of the mating drill pipe;  
 the pin tool joint and the box tool joint each having a substantially uniform tool joint outer diameter, TJ OD , along its axial length and a substantially uniform tool joint inner diameter, TJ ID , along its axially  axial length; and  
 the drill pipe having a ratio, R, expressed as: 
       8.8   ≥         P   ID     +     TJ   ID           TJ   OD     -     P   OD         ≥     8.0   .         
 
 
     
     
       2. The drill pipe as defined in  claim 1 , wherein R is from 8.1 to 8.5. 
     
     
       3. The drill pipe as defined in  claim 2 , wherein R is from 8.2 to 8.4. 
     
     
       4. The drill pipe as defined in  claim 1 , wherein the pipe section outer diameter, P OD , is from 5¾ inches to 6 inches. 
     
     
       5. The drill pipe as defined in  claim 1 , wherein the tool joint outer diameter, TJ OD , is less than or equal to 7 inches. 
     
     
       6. The drill pipe as defined in  claim 1 , wherein the tool joint inner diameter, TJ ID , is greater than or equal to 4 inches. 
     
     
       7. The drill pipe as defined in  claim 6 , wherein the tool joint inner diameter, TJ ID , is less than or equal to 4¼ inches. 
     
     
       8. The drill pipe as defined in  claim 1 , wherein the pin tool joint internal thread and the box tool joint external thread are each tapered. 
     
     
       9. The drill pipe as defined in  claim 1 , when  wherein the pin tool joint and the box tool joint are each welded to the pipe. 
     
     
       10. The drill pipe as defined in  claim 1 , further comprising:
 another pin shoulder on the pin tool joint;  
 another box shoulder on the box tool joint; and  
 the another pin shoulder mates with the another box shoulder of the mating drill pipe.  
 
     
     
       11. A drill pipe with enhanced strength and fluid flow capability, the drill pipe comprising:
 an elongate pipe section having a central axis, a substantially uniform pipe outer diameter, P OD , of from 5¾ inches to 6 inches along its axial length, and a substantially uniform pipe inner diameter, P ID , along its axial length;  
 a pin tool joint connected by welding to an axial end of the pipe section, the pin tool joint having external pin threadsand a pin shoulder ;  
 a box tool joint connected by welding to an axial end of the pipe section opposing the pin tool joint, the box tool joint having internal box threads for mating engagement with the external pin threads of a mating drill pipeand a box shoulder for engagement with the pin shoulder of the mating drill pipe ;  
 the pin tool joint and the box tool joint each having a substantially uniform tool joint outer diameter, TJ OD , less than or equal to 7 inches along its axial length and a substantially uniform tool joint inner diameter, TJ ID , of at least 4 inches along its axially  axial length; and  
 the drill pipe having a ratio, R, expressed as: 
       8.8   ≥         P   ID     +     TJ   ID           TJ   OD     -     P   OD         ≥     8.0   .         
 
 
     
     
       12. The drill pipe as defined in  claim 11 , wherein R is from 8.1 to 8.5. 
     
     
       13. The drill pipe as defined in  claim 11 , wherein the tool joint inner diameter, TJ ID , is less than or equal to 4¼ inches. 
     
     
       14. The drill pipe as defined in  claim 11 , wherein the pin tool joint internal thread and the box tool joint external thread are each tapered. 
     
     
       15. The drill pipe as defined in  claim 11 , further comprising:
 anothera pin shoulder on the pin tool joint;  
 anothera box shoulder on the box tool joint; and  
 the another  pin shoulder mates with the another  box shoulder of the mating drill pipe.  
 
     
     
       16. A drill pipe with enhanced strength and fluid flow capability, the drill pipe comprising:
 an elongate pipe section having a central axis, a substantially uniform pipe outer diameter, P OD , of from  5   3 / 4  inches to  6  inches along its axial length, and a substantially uniform pipe inner diameter, P ID , along its axial length;  
 a pin tool joint connected by welding to an axial end of the pipe section, the pin tool joint having external pin threads and first and second axially spaced pin shoulders;  
 a box tool joint connected by welding to an axial end of the pipe section opposing the pin tool joint, the box tool joint having internal box threads for mating engagement with the external pin threads of a mating drill pipe and first and second axially spaced box shoulders each for engagement with a respective pin shoulder of the mating drill pipe;  
 the pin tool joint and the box tool joint each having a substantially uniform tool joint outer diameter, TJ OD , less than or equal to 7 inches along its axial length and a substantially uniform tool joint inner diameter, TJ ID , along its axial length;  
 the elongate pipe section having an internal upset region at each axial end thereof, each upset region having an enhanced wall thickness and an internal upset diameter approximating the tool joint inner diameter, TJ ID ; and  
 the drill pipe having a ratio, R, expressed as: 
       8.8   ≥         P   ID     +     TJ   ID           TJ   OD     -     P   OD         ≥     8.0   .         
 
 
     
     
       17. The drill pipe as defined in  claim 16 , wherein R is from 8.1 to 8.5. 
     
     
       18. The drill pipe as defined in  claim 16 , wherein the pipe section outer diameter, P OD , is from 5¾ inches to 6 inches. 
     
     
       19. The drill pipe as defined in  claim 16 , wherein the tool joint inner diameter, TJ ID , is greater than or equal to 4 inches and is less than or equal to 4¼ inches. 
     
     
       20. The drill pipe as defined in  claim 16 , wherein the pin tool joint internal thread and the box tool joint external thread are each tapered. 
     
     
       21. A drill pipe with enhanced strength and fluid flow capability, the drill pipe comprising:
   an elongate pipe section having a central axis, a substantially uniform pipe outer diameter, P   OD   , along its axial length, and a substantially uniform pipe inner diameter, P   ID   , along its axial length, the pipe outer diameter, P   OD   , being  5   3 / 4  inches or greater;        a pin tool joint connected by welding to an axial end of the pipe section, the pin tool joint having external pin threads;        a box tool joint connected by welding to an axial end of the pipe section opposing the pin tool joint, the box tool joint having internal box threads for mating engagement with the external pin threads of a mating drill pipe;        the pin tool joint and the box tool joint each having a substantially uniform tool joint outer diameter, TJ   OD   , less than or equal to  7  inches along at least an upper portion of its axial length and a substantially uniform tool joint inner diameter, TJ   ID   , along its axial length;        the elongate pipe section having an internal upset region at each axial end thereof, each upset region having an enhanced wall thickness and an internal upset diameter approximating the tool joint inner diameter, TJ   ID   ; and        the drill pipe having a ratio, R, expressed as:          8.8   ≥         P   ID     +     TJ   ID           TJ   OD     -     P   OD         ≥     8.0   .             
       
        
       
     
     
       22. The drill pipe as defined in  claim 21 , wherein R is from  8 . 1  to  8 . 5 . 
     
     
       23. The drill pipe as defined in  claim 21 , wherein the pipe section outer diameter, P OD   , is less than about  6  inches.   
     
     
       24. The drill pipe as defined in  claim 21 , wherein the tool joint inner diameter, TJ ID   , is greater than or equal to  4  inches and is less than or equal to  4   1 / 4  inches.   
     
     
       25. The drill pipe as defined in  claim 21 , wherein the pin tool joint internal thread and the box tool joint external thread are each tapered.