Methods and systems for wiping surfaces when performing subterranean operations

Abstract

Improved darts and methods of using these darts in subterranean wells are disclosed. The improved dart comprises a foam portion and a rubber portion coupled to the foam portion. A dart nose is coupled to at least one of the foam portion and the rubber portion. The foam portion and the rubber portion are configured to interface with an inner surface of at least one of a well bore wall, a pipe, and a casing string.

What is claimed is: 
     
         1 . A dart comprising:
 a foam portion;   a rubber portion coupled to the foam portion; and   a dart nose coupled to at least one of the foam portion and the rubber portion;
 wherein the foam portion and the rubber portion are configured to interface with an inner surface of at least one of a well bore wall, a pipe, and a casing string. 
   
     
     
         2 . The dart of  claim 1 , wherein the foam portion is made from a gel material. 
     
     
         3 . The dart of  claim 1 , wherein the rubber portion is made from polyurethane. 
     
     
         4 . The dart of  claim 1 , wherein the foam portion and the rubber portion are detachably coupled. 
     
     
         5 . The dart of  claim 4 , wherein at least one of a threaded engagement, a bolt, and a screw detachably couples the foam portion to the rubber portion. 
     
     
         6 . The dart of  claim 1 , wherein the foam portion and the rubber portion are non-detachably coupled. 
     
     
         7 . The dart of  claim 1 , wherein the foam portion comprises at least one of a conical portion, a cylindrical portion, an elliptical portion and a combination thereof. 
     
     
         8 . The dart of  claim 1 , wherein the rubber portion comprises at least one of a conical portion, a cylindrical portion, an elliptical portion and a combination thereof. 
     
     
         9 . A method of cleaning a restriction in a casing comprising:
 placing a dart in the restriction;
 wherein the dart comprises a foam portion coupled to a rubber portion; 
   passing the dart through the restriction;
 wherein at least one of the foam portion and the rubber portion cleans an 
 inner surface of the restriction; and 
   directing the dart out of the restriction to a wider portion of the casing;
 wherein a diameter of the wider portion of the casing exceeds a diameter of the restriction; and 
 wherein the rubber portion interfaces with an inner surface of the wider portion of the casing before the foam portion interfaces with an inner surface of the wider portion of the casing. 
   
     
     
         10 . The method of  claim 9 , wherein the foam portion is made from a gel material. 
     
     
         11 . The method of  claim 9 , wherein the rubber portion is made from polyurethane. 
     
     
         12 . The method of  claim 9 , wherein the foam portion and the rubber portion are detachably coupled. 
     
     
         13 . The method of  claim 12 , wherein at least one of a threaded engagement, a bolt, and a screw detachably couples the foam portion to the rubber portion. 
     
     
         14 . The method of  claim 9 , wherein the foam portion and the rubber portion are non-detachably coupled. 
     
     
         15 . The dart of  claim 9 , wherein the foam portion comprises at least one of a conical portion, a cylindrical portion, an elliptical portion and a combination thereof. 
     
     
         16 . The dart of  claim 9 , wherein the rubber portion comprises at least one of a conical portion, a cylindrical portion, an elliptical portion and a combination thereof.