US 11,053,769 B2
Back pressure valve plug
James D. Craycraft, Soldotna, AK (US)
Assigned to Northern Oil Solutions, Soldotna, AK (US)
Filed by Northern Oil Solutions, Soldotna, AK (US)
Filed on Nov. 7, 2019, as Appl. No. 16/677,467.
Claims priority of provisional application 62/918,494, filed on Feb. 2, 2019.
Prior Publication US 2020/0248523 A1, Aug. 6, 2020
Int. Cl. E21B 33/12 (2006.01); E21B 34/02 (2006.01); E21B 33/04 (2006.01); E21B 47/117 (2012.01)
CPC E21B 33/12 (2013.01) [E21B 33/04 (2013.01); E21B 34/02 (2013.01); E21B 47/117 (2020.05)] 19 Claims
OG exemplary drawing
 
1. A valve and plug tool configured for use in a tubing hanger associated with a wellhead of a well, the tool comprising:
a back-pressure valve (BPV) removably disposable in the tubing hanger and configured to isolate tubing and seal bottom hole pressure from the well while allowing fluid to be pumped into the tubing, defining a check-valve, and comprising:
a valve body with external screw threads configured to threadably engage the tubing hanger;
a bore extending through the valve body;
a poppet movable in the bore and biased against a seat in the valve body;
a slot in a top of the valve body configured to receive a tool for setting and removing the BPV with respect to the tubing hanger;
internal screw threads in the bore between the poppet and the slot;
an annular, circumferential inner wall in the bore and positioned between the slot and the internal screw threads with an axially flat surface without screw threads, defining a seal surface; and
an annular step in the bore defining a stop; and
a plug removably couplable to the BPV and configured to selectively and completely plug the bore of the BPV, and configured to completely plug the BPV, and comprising:
a plug body with opposite upper and lower ends;
lower screw threads on the lower end of the plug body and matching the internal screw threads of the valve body of the BPV to form a threaded connection between the plug and the BPV and removably couple the plug to the BPV;
an annular grove circumscribing the plug body above the lower screw threads;
a seal carried in the annular grove and located above the lower screw threads, and configured to seal between the annular groove of the plug body and the seal surface of the bore of the BPV above the threaded connection when the plug body is coupled to the BPV;
an annular flange circumscribing the plug body and configured to abut to the annular step in the bore of the valve body, the annular step and the annular flange positioned with respect to the valve body and the plug body, respectively, to define a full stop of the plug with respect to the BPV short of engaging the poppet; and
upper screw threads near the upper end of the plug body, the upper screw threads being different than the lower screw threads of the plug and the internal screw threads of the BPV, the upper screw threads defining retrieving threads configured to match internal screw threads of a retrieval tool.