Hang-free thread design

Abstract

A threaded pin and box connection having thread geometries and/or dissimilar thread fits that prevent the pin thread of a connection from hanging up in the box thread as the pin is being stabbed into or destabbed from the box. Dissimilar geometries and/or threads include dissimilar thread types, dissimilar leads, overlapping leads, thread tooth widths of one component greater than thread grooves of the other component, multiple start threads, and combinations thereof.

1 - 13 . (canceled)  
   
   
       14 . A multi-step thread connector as defined in  claim 63  further comprising pin and box thread teeth that are adapted to engage with each other in a wedge-thread.  
   
   
       15 - 22 . (canceled)  
   
   
       23 . A multi-step threaded connection as defined in  claim 64  further including a pin connection having a pin thread tooth with a width that increases along a helical thread development in a direction away from a nearest axial end of said pin.  
   
   
       24 . A multi-step threaded connection as defined in  claim 64  further comprising pin and box thread teeth adapted to engage and form a wedge-thread.  
   
   
       25 . A multi-step threaded connection as defined in  claim 64  further comprising pin and box thread teeth adapted to engage and form a hook thread.  
   
   
       26 . A multi-step threaded connection as defined in  claim 64  wherein said pin and box thread teeth have cross sectional profiles with at least one thread flank of each thread tooth being parallel with a thread flank of the other thread tooth.  
   
   
       27 . A multi-step threaded connection as defined in  claim 64  further comprising pin and box thread teeth adapted to threadedly engage with each other in a dovetail connection.  
   
   
       28 . A multi-step threaded connection as defined in  claim 27  further comprising pin and box thread teeth adapted to engage with each other to form a wedge-thread.  
   
   
       29 - 35 . (canceled)  
   
   
       36 . A threaded connection having a pin receivable within a box and adapted to be threadedly engaged and disengaged to selectively secure tubular members together, comprising: 
 an axially extending pin connection having a helical pin thread crest at a radially outer point on a pin thread tooth, said pin thread crest having a crest width,    a helical box thread tooth defining a helical box thread groove between adjacent turns of said box thread tooth, said box thread groove having a groove width, and    said pin thread crest being wider than said box groove width in adjacent pin and box threads at all positions where the pin and box threads are disengaged and the pin is at least partially received in the box.    
   
   
       37 . A threaded connection as defined in  claim 36  wherein said pin thread tooth has a width that increases along the helical thread development in a direction away from a nearest axial end of said pin.  
   
   
       38 . A threaded connection as defined in  claim 36  further comprising pin and box thread teeth adapted to engage and form a wedge-thread.  
   
   
       39 . A threaded connection as defined in  claim 36  further comprising pin and box thread teeth adapted to engage and form a hook thread.  
   
   
       40 . A threaded connection as defined in  claim 36  wherein said pin and box thread teeth have cross sectional profiles with at least one thread flank of each thread being parallel with a thread flank of the other.  
   
   
       41 . A threaded connection as defined in  claim 36  further comprising pin and box thread teeth adapted to threadedly engage each other in a dovetail connection.  
   
   
       42 . A threaded connector as defined in  claim 41  further comprising pin and box thread teeth adapted to engage in a wedge-thread.  
   
   
       43 . (canceled)  
   
   
       44 . A method of manufacturing a threaded pin and box connector, comprising: 
 forming a helically extending pin thread tooth on a pin of said connector,    forming a pin thread crest on said pin thread tooth,    forming a helically extending box thread tooth on a box of said connector,    forming a box thread groove between adjacent turns of said box thread tooth, and    forming said pin thread crest with a width greater than the width of said box thread groove on substantially all pin thread teeth that may be received within said box without also being threadedly engaged in said box.    
   
   
       45 . A multi-step threaded connector, comprising: 
 a pin connection having a large diameter pin thread area and a smaller diameter pin thread area formed about a central pin axis,    a box connection with a large diameter box thread area and a smaller diameter box thread area formed about a central box axis, said large diameter pin thread area being threadedly receivable within said large diameter box thread area and said smaller diameter pin thread area being threadedly receivable within said smaller diameter box thread area,    a pin thread tooth coaxially formed externally on said smaller diameter pin thread area, said pin thread tooth advancing helically from one axial point on said pin connection toward a nearest axial end of said pin connection,    a pin crest on said pin thread tooth, said pin crest having a crest width measured parallel to said pin axis,    a box thread tooth coaxially formed internally on said large diameter box thread area, said box thread tooth advancing helically from one axial point on said box connection toward a nearest axial end of said box connection, and    wherein the lead of said box thread tooth is different from the lead of said pin thread tooth in areas in which said box thread tooth overlaps said pin thread tooth during stabbing and destabbing of said pin and box.    
   
   
       46 . A multi-step thread connector as defined in  claim 45  wherein the width of said pin thread tooth increases along the helical thread development in a direction away from said axial end of said pin.  
   
   
       47 . A multi-step thread connector as defined in  claim 45  further comprising pin and box thread teeth adapted to engage in a wedge-thread.  
   
   
       48 . A multi-step thread connector as defined in  claim 45  further comprising pin and box thread teeth adapted to engage in a hook thread.  
   
   
       49 . A multi-step thread connector as defined in  claim 45  wherein said pin and box thread teeth have cross sectional profiles with at least one thread flank of each thread being parallel with a thread flank of the other.  
   
   
       50 . A multi-step thread connector as defined in  claim 45  further comprising pin and box thread teeth adapted to threadedly engage with each other in a dovetail connection.  
   
   
       51 . A multi-step thread connector as defined in  claim 50  further comprising pin and box thread teeth adapted to engage in a dovetail wedge-thread.  
   
   
       52 . A multi-step thread connector as defined in  claim 45  wherein the average lead of a pin thread tooth is equal to the average lead of a box thread tooth.  
   
   
       53 . A multi-step thread connector as defined in  claim 52  wherein the lead between box thread tooth load flanks is a dimension “C”, the lead between box thread tooth stab flanks is a dimension “D”, the lead between pin thread tooth load flanks is a dimension “E”, the lead between pin thread tooth stab flanks is a dimension “F”, and wherein C is less than E and D is greater than F.  
   
   
       54 . A multi-step thread connector as defined in  claim 51  wherein the lead between box thread tooth load flanks is a dimension “C”, the lead between box thread tooth stab flanks is a dimension “D”, the lead between pin thread tooth load flanks is a dimension “E”, the lead between pin thread tooth stab flanks is a dimension “F”, and wherein C is less than E and D is greater than F.  
   
   
       55 - 59 . (canceled)  
   
   
       60 . A multi-step threaded pin connection having first and second threaded areas, said first threaded area having a smaller diameter than said second threaded area, comprising: 
 a first thread tooth extending helically over said first threaded area,    a second thread tooth extending helically over said second threaded area,    said first tooth having a first tooth crest positioned between a stab flank and a load flank of said first tooth, and    said second tooth having a second tooth crest positioned between a stab flank and a load flank of said second tooth, said second tooth crest being larger than said first tooth crest, said pin and box thread teeth being adapted to threadedly engage with each other in a wedge-thread.    
   
   
       61 . A multi-step threaded pin connection having first and second threaded areas, said first threaded area having a smaller diameter than said second threaded area, comprising: 
 a first thread tooth extending helically over said first threaded area,    a second thread tooth extending helically over said second threaded area,    said first tooth having a first tooth crest positioned between a stab flank and a load flank of said first tooth, and    said second tooth having a second tooth crest positioned between a stab flank and a load flank of said second tooth, said second tooth crest being larger than said first tooth crest, said pin and box thread teeth being adapted to engage with each other in a hook thread.    
   
   
       62 . A multi-step threaded pin connection having first and second threaded areas, said first threaded area having a smaller diameter than said second threaded area, comprising: 
 a first thread tooth extending helically over said first threaded area,    a second thread tooth extending helically over said second threaded area,    said first tooth having a first tooth crest positioned between a stab flank and a load flank of said first tooth, and    said second tooth having a second tooth crest positioned between a stab flank and a load flank of said second tooth, said second tooth crest being larger than said first tooth crest, said pin and box thread teeth being cross sectional profiles with at least one thread flank of each thread being parallel with a thread flank of the other.    
   
   
       63 . A multi-step threaded pin connection having first and second threaded areas, said first threaded area having a smaller diameter than said second threaded area, comprising: 
 a first thread tooth extending helically over said first threaded area,    a second thread tooth extending helically over said second threaded area,    said first tooth having a first tooth crest positioned between a stab flank and a load flank of said first tooth, and    said second tooth having a second tooth crest positioned between a stab flank and a load flank of said second tooth, said second tooth crest being larger than said first tooth crest, said pin and box thread teeth being adapted to threadedly engage with each other in a dovetail connection.    
   
   
       64 . A multi-step threaded box connection having first and second threaded areas, said first threaded area having a larger diameter than said second threaded area, comprising: 
 a first thread tooth formed helically over said first threaded area defining a first thread groove between adjacent helical sections of said first thread tooth,    a second thread tooth formed helically over said second threaded area defining a second thread groove between adjacent helical sections of said second thread tooth, said second thread groove being wider than said first thread groove, and    a central axis in said connection with said first and second thread teeth extending helically and axially along an inner surface of said box connection, said box teeth defining box thread grooves between adjacent helical sections of said thread teeth, said box thread grooves having widths that decrease in width in a direction away from a nearest axial end of said box connection.