Seal cup for a wellbore tool and method
A seal cup and method is disclosed that can be used on a wellbore tool. The seal cup includes an external circumferential seal land adjacent the cup lip and an outer surface capable of permitting drainage away from the seal land of fluids, which may seep past the seal land. This acts against pressure invasion in the interfacial contacting region between the seal cup and the structure, for example, a wellbore liner against which it is sealed.
1. A wellbore tool comprising:
a body,
a cup seal carried at a lower end of the body, the cup seal having an outer surface with at least a portion containing friction enhancing material;
a seal surface on its outer diameter; and
a friction reducing insert mounted on the outer diameter of the cup seal, the insert located to contact the wellbore when the tool is in use.
2. A wellbore pump down plug comprising:
a body;
an upper seal mounted to the body having a seal surface on its outer diameter;
a cup seal carried at a lower end of the body, the cup seal having a seal surface on its outer diameter;
a friction enhancing material mounted on the outer diameter of the cup seal; and
a friction reducing insert mounted on the outer diameter of the cup seal, the insert located to contact a string of tubulars when the tool is in use.
3. A method for positioning a wellbore tool body in a wellbore, the method comprising:
(a) attaching a cup seal to a lower end of a wellbore tool body, the cup seal having an outer surface containing friction enhancing material, and
(b) pumping the body down a wellbore to a selected downhole position, with the cup seal sealing against a pressure that is higher below the cup seal than above it.
4. The method of claim 3 , wherein pumping includes latching the wellbore tool body to the wellbore.
5. The method of claim 3 , wherein attaching further comprises attaching an upper seal to the wellbore tool body above the cup seal, and
pumping comprises applying a differential pressure to the upper seal.
6. The method of claim 3 , wherein during pumping the outer surface of the cup seal engages the wellbore.
7. The method of claim 6 , wherein attaching further comprises mounting a friction reducing insert on the outer surface of the cup seal at a point where it engages the wellbore.
8. A method for positioning a wellbore tool body in a well comprising:
(a) attaching a cup seal to a lower end of a body, the cup seal having an outer surface containing friction enhancing material, and
(b) pumping the body down a string of tubulars installed in a well to a selected downhole position, with the cup seal sealing against a pressure that is higher below the cup seal than above it.
9. The method of claim 8 , wherein attaching further comprises mounting a friction reducing insert on the outer surface of the cup seal, and
during pumping the insert engages the string of tubulars.