Universal pressure protector for a polish rod

Abstract

Method and apparatus for protecting a wellhead drive assembly has a housing having a polish rod seal and utilizes standard flanges adapted to fit between the existing stuffing box of any wellhead drive assembly and the standard flange of a well for extending the longevity of the existing stuffing box. In another embodiment, the housing, with or without a polish rod seal, protects the wellhead drive assembly and sealing components from damage due to flushing pressures. The protector housing introduces a sealing ring adjacent the well end that seals around a tapered rod coupler of the polish rod when so lifted for preventing high flushing pressure from being exerted directly onto seal elements thereabove. As in the first embodiment, a polish rod seal can be fit to the housing for protecting a stuffing box portion of the wellhead assembly in addition to the sealing ring used for protection during flushing operations.

1 . Apparatus for sealing a polish rod below a wellhead drive assembly connected to a well, the polish rod having a tapered rod coupler at a bottom end, the apparatus comprising: 
 a housing having a top end adapted for connection to the wellhead drive assembly and a bottom end adapted for connection to the well, the housing having a bore for passing the polish rod therethrough; and    a sealing ring positioned in the bore adjacent the bottom end,    wherein when the polish rod is lifted to contact the tapered rod coupler with the sealing ring the well is isolated from the top end of the housing.    
   
   
       2 . The apparatus of  claim 1  further comprising: 
 a reduced diameter section of the bore adjacent the housing's bottom end for retaining a polish rod seal in the bore thereabove and for forming a point against which the tapered rod coupler comes to rest when the polish rod is lifted; and    wherein the sealing ring is positioned below the reduced diameter section.    
   
   
       3 . The apparatus of  claim 2  wherein the polish rod seal further comprises a top bushing, a bottom bushing and packing rings therebetween.  
   
   
       4 . The apparatus of  claim 3  wherein the bottom bushing is supported on the reduced diameter section of the bore.  
   
   
       5 . The apparatus of  claim 1  wherein the sealing ring is secured in the bottom end of the housing with a lock-down ring.  
   
   
       6 . The apparatus of  claim 3  wherein the top bushing is secured in the top end of the housing with a lock-down ring.  
   
   
       7 . The apparatus of  claim 3  wherein packing rings further comprise: 
 a first plurality of packing rings;    a second plurality of packing rings; and    a spring positioned therebetween.    
   
   
       8 . The apparatus of  claim 3  wherein the top bushing is secured in the top end of the housing with a lock-down ring.  
   
   
       9 . The apparatus of  claim 8  wherein the lock-down ring is threaded into the top end of the housing for compressing the spring.  
   
   
       10 . The apparatus of  claim 3  wherein the bottom bushing further comprises wiper rings for cleaning the polish rod.  
   
   
       11 . The apparatus of  claim 1  wherein the housing extends the wellhead drive assembly a greater distance above the well.  
   
   
       12 . A system for sealing a polish rod in a well comprising: 
 a wellhead drive assembly having a polish rod sealing stuffing box adapted for connection to the well and the polish rod extending therethrough;    a protector housing having a top end adapted for connection to the stuffing box and a bottom end adapted for connection to the well, the housing having a bore for passing the polish rod therethrough; and    a polish rod seal in the bore of the housing,    wherein the protector housing seals the polish rod before the polish rod extends through the stuffing box.    
   
   
       13 . The system of  claim 12  wherein the polish rod has tapered rod coupler at a bottom end and the polish rod seal further comprises: 
 a top bushing, a bottom bushing and packing rings therebetween;    a reduced diameter section of the bore adjacent the housing's bottom end for retaining the bottom bushing in the bore thereabove and for forming a point against which the tapered rod coupler comes to rests when the polish rod is lifted; and    a sealing ring positioned in the bore adjacent the bottom end,    wherein when the polish rod is lifted to contact the tapered rod coupler with the sealing ring the well is isolated from the top end of the housing.    
   
   
       14 . The system of  claim 13  wherein packing rings further comprise: 
 a first plurality of packing rings;    a second plurality of packing rings; and    a spring positioned therebetween.    
   
   
       15 . The system of  claim 14  wherein the top bushing is adjusted relative to the top end of the housing for compressing the spring.  
   
   
       16 . The system of  claim 12  wherein the housing is extends the wellhead drive assembly a greater distance above the well.  
   
   
       17 . A method for sealing a polish rod below a wellhead drive assembly connected to a well while flushing the well under pressure, the polish rod having a tapered rod coupler at a bottom end, the method comprising: 
 providing a housing between the wellhead drive assembly and the well, the polish rod passing therethrough and having a reduced diameter section of the bore adjacent the housing's bottom end and sealing ring therebelow;    lifting the polish rod to rest the tapered rod coupler against the reduced diameter section and seal against the sealing ring; and    applying pressure to the well for flushing the well wherein the sealing ring protects the wellhead drive assembly from the pressure in the well.    
   
   
       18 . The method of  claim 17  wherein the wellhead drive assembly has a polish rod sealing stuffing box adapted for connection to the well and the polish rod extending therethrough, the method further comprising: 
 connecting the housing to the stuffing box; and when the polish rod is lifted,    protecting the stuffing box from the pressure in the well.    
   
   
       19 . The method of  claim 18  wherein the housing further has a polish rod seal, the method further comprising: 
 sealing the well from the stuffing box at the polish rod seal; and when the polish rod is lifted,    protecting the polish rod seal and the stuffing box from the pressure in the well.    
   
   
       20 . Apparatus for sealing a polish rod below a wellhead drive assembly having a stuffing box connected to a well, the stuffing box and well having a standard flange connection therebetween, the apparatus comprising: 
 a housing having a bore for passing the polish rod therethrough;    a standard flange at a top end of the housing for connection to the stuffing box of the wellhead drive assembly;    a standard flange at a bottom end of the housing for connection to the well; and    a polish rod seal in the bore of the housing protecting the stuffing box from pressure in the well.    
   
   
       21 . The apparatus of  claim 20  further comprising: 
 a bottom bushing retained in the bore of the housing;    a top bushing; and wherein the polish rod seal is positioned therebetween.    
   
   
       22 . The apparatus of  claim 20  wherein the polish rod seal comprises packing rings.  
   
   
       23 . The apparatus of  claim 22  wherein packing rings further comprise: 
 a first plurality of packing rings;    a second plurality of packing rings; and    a spring positioned therebetween.    
   
   
       24 . The apparatus of  claim 21  wherein the top bushing is secured in the top end of the housing with a lock-down ring.  
   
   
       25 . The apparatus of  claim 24  wherein the lock-down ring is threaded into the top end of the housing for compressing the spring.  
   
   
       26 . The apparatus of  claim 21  wherein the bottom bushing further comprises wiper rings for cleaning the polish rod.  
   
   
       27 . The apparatus of  claim 20  wherein the polish rod has a tapered rod coupler at a bottom end of the polish rod, the apparatus further comprising: 
 a sealing ring positioned in the bore adjacent the bottom end of the housing, wherein when the polish rod is lifted to contact the tapered rod coupler with the sealing ring the well is isolated from the top end of the housing.    
   
   
       28 . The apparatus of  claim 27  wherein the sealing ring is secured in the bottom end of the housing with a lock-down ring.  
   
   
       29 . The apparatus of  claim 27  wherein: 
 the reduced diameter section of the bore adjacent the housing's bottom end forms a point against which the tapered rod coupler comes to rest when the polish rod is lifted, and    the sealing ring is positioned below the reduced diameter section.    
   
   
       30 . The apparatus of  claim 20  wherein the housing extends the wellhead drive assembly a greater distance above the well.