Valve Apparatus Having Dissolvable or Frangible Flapper and Method of Using Same
A bridge plug for use in a wellbore having an anchoring system to grip the inner surface of the surrounding wellbore, as well as a sealing system or packing element to seal against the inner surface. A hinged flapper permits flow of fluid in one axial direction through a central through bore, but can selectively contact against a seat to create a fluid pressure seal and prevent fluid flow through said central through bore in an opposite axial direction. The flapper can be manufactured of frangible material and/or dissolvable material, permitting selective removal of the flapper when desired.
1 . A valve assembly comprising:
a) a body section having an upper surface, outer surface, and a central flow bore defining a first diameter, and having an upper opening defining a seat at said upper surface;
b) at least one slip member disposed on said outer surface adapted to selectively grip against an inner surface of a wellbore;
c) at least one elastomeric sealing member disposed on said outer surface adapted to selectively form a fluid pressure seal against said inner surface of said wellbore;
d) a flapper hingedly attached to said body section, wherein said flapper can move between a substantially open configuration, and a substantially closed configuration wherein said flapper contacts said seat and said transverse support member; and
e) a spring configured to bias said flapper off of said seat until fluid pressure acting on said flapper overcomes force exerted by said spring.
2 . The valve assembly of claim 1 , wherein said valve assembly can be conveyed into said wellbore on wireline and set using a wireline setting tool.
3 . The valve assembly of claim 1 , wherein said valve assembly can be conveyed into said wellbore on pipe and set using a hydraulic setting tool.
4 . The valve assembly of claim 1 , wherein said flapper is constructed of frangible material adapted to selectively break into smaller pieces in response to application of a predetermined force to said flapper.
5 . The valve assembly of claim 4 , wherein said smaller pieces can be circulated out of said wellbore when broken.
6 . The valve assembly of claim 1 , wherein said flapper is constructed of dissolvable material.
7 . The valve assembly of claim 6 , wherein said dissolvable flapper is adapted to substantially uncover said central flow bore after dissolving.
8 . A method of performing hydraulic fracturing operations in a wellbore comprising:
a) conveying a valve assembly into a wellbore, wherein said valve assembly comprises:
i) a body section having an upper surface, an outer surface and a central flow bore defining a first diameter, and having an upper opening defining a seat at said upper surface;
ii) at least one slip member disposed on said outer surface adapted to selectively grip against an inner surface of said wellbore;
iii) at least one elastomeric sealing member disposed on said outer surface adapted to selectively form a fluid pressure seal against the inner surface of said wellbore;
iv) a flapper hingedly attached to said body section, wherein said flapper can move between a substantially open configuration, and a substantially closed configuration wherein said flapper contacts said seat and said transverse support member;
v) a spring configured to bias said flapper off of said seat;
b) setting said valve assembly at a desired position in said wellbore;
c) applying fluid pressure to said flapper;
d) closing said flapper when fluid pressure applied to said flapper overcomes force exerted by said spring; and
e) conducting hydraulic fracturing operations in said wellbore.
9 . The method of claim 8 , wherein said valve assembly is conveyed into said wellbore on wireline and set using a wireline setting tool.
10 . The method of claim 8 , wherein said valve assembly is conveyed into said wellbore on pipe and set using a hydraulic setting tool.
11 . The method of claim 8 , wherein said flapper is constructed of frangible material adapted to selectively break into smaller pieces in response to application of a predetermined force to said flapper.
12 . The method of claim 11 , wherein said smaller pieces can be circulated out of said wellbore when broken.
13 . The method of claim 8 , wherein said flapper is constructed of dissolvable material.
14 . The method of claim 13 , wherein said dissolvable flapper is dissolved to substantially uncover said central flow bore following completion of said hydraulic fracturing operations.
15 . A valve assembly comprising:
a) a body section having an upper surface, a lower surface, an outer surface, a central flow bore defining a first diameter, and having an upper opening defining a seat at said upper surface, a hinge post disposed at said upper surface, and notch disposed at said lower surface;
b) a support ring disposed at said seat and defining a second diameter;
c) at least one ball transfer unit disposed on said outer surface configured to contact an inner surface of a wellbore;
d) at least one slip member disposed on said outer surface configured to selectively grip against said inner surface of said wellbore;
e) at least one elastomeric sealing member disposed on said outer surface adapted to selectively form a fluid pressure seal against said inner surface of said wellbore; and
f) a flapper hingedly attached to said hinge post of said body section, wherein said flapper can move between a substantially open configuration, and a substantially closed configuration wherein said flapper contacts said seat and said transverse support member.
16 . The valve assembly of claim 15 , wherein said flapper and said support ring are constructed of frangible material adapted to selectively break into smaller pieces in response to application of a predetermined force to said flapper and said support ring.
17 . The valve assembly of claim 16 , wherein said smaller pieces can be circulated out of said wellbore when broken.
18 . The valve assembly of claim 15 , wherein said flapper and said support ring are constructed of dissolvable material.
19 . The valve assembly of claim 18 , wherein said dissolvable flapper and said dissolvable support ring are adapted to substantially uncover said central flow bore after dissolving.
20 . The valve assembly of claim 15 , wherein said hinge post is configured to be selectively received within a notch of an adjacent valve assembly disposed in said wellbore.