Stationary plunger packing

1 . A reciprocating pump system comprising:

a fluid end comprising:

a body;

a plurality of plungers, each plunger reciprocable within a corresponding bore in the body;

for each plunger, a dynamic packing disposed in the bore around the plunger and configured to be energized into dynamic engagement around the plunger against pressure from a pressure side;

for each plunger, a dynamic packing nut engageable with an atmospheric side of the dynamic packing opposite the pressure side to energize the dynamic packing; and

a static packing in each dynamic packing nut configured to be energized by mechanical force into static sealing engagement around the plunger against pressure from a pressure side,

wherein when one of the plungers is being reciprocated, the dynamic packing corresponding to that plunger is energized by the dynamic packing nut and the static packing corresponding to that plunger is deenergized, and

wherein when one of the plungers is no longer being reciprocated, the static packing corresponding to that plunger is energized into static sealing engagement with the plunger.

2 . The pump system of claim 1 , further comprising, for each plunger, a static packing nut engageable with the dynamic packing nut corresponding to that plunger and an atmospheric side of the static packing corresponding to that plunger opposite the pressure side to energize the static packing.

3 . The pump system of claim 1 , further comprising, for each plunger, a retainer independently operable to engage an atmospheric side of the static packing corresponding to that plunger opposite the pressure side to energize the static packing.

4 . The pump system of claim 1 , wherein, for each plunger, the dynamic packing nut corresponding to that plunger comprises an actuator operable to engage an atmospheric side of the static packing corresponding to that plunger opposite the pressure side to energize the static packing for that plunger.

5 . The pump system of claim 1 , wherein the fluid end further comprises a pump chamber within the body and the bores extend into the body and into fluid communication with the pump chamber, wherein the plungers are configured to be reciprocated within corresponding bores by moving in a forward direction toward the pump chamber in a forward stroke and in a return direction away from the pump chamber in a return stroke.

6 . The pump system of claim 1 , wherein the dynamic packing nuts are engageable with the dynamic packings by being threaded into the body.

7 . The pump system of claim 1 , wherein, for each plunger, the static packing retainer is engageable with the dynamic packing nut corresponding to that plunger by being threaded into the dynamic packing nut.

8 . The pump system of claim 7 , wherein the static packing nuts are threaded into the dynamic packing nuts using a motor.

9 . The pump system of claim 1 , further comprising a power source operable to reciprocate push rods, each push rod releasably coupled to the plunger corresponding to that push rod, wherein reciprocation of the push rods reciprocates the plungers within the bores.

10 . A method of operating a reciprocating pump comprising:

reciprocating plungers in bores of a fluid end;

dynamically sealing the plungers with dynamic packings in the bores against pressure on a pressure side of the dynamic packings while the plungers are reciprocating and while static packings are deenergized;

selectively decoupling an identified plunger from the push rod corresponding to that plunger such that the identified plunger is stationary; and

energizing the respective static packing for the identified plunger into static sealing engagement with the stationary plunger.

11 . The method of claim 10 wherein dynamically sealing the plungers comprises engaging atmospheric sides of dynamic packings opposite the pressure sides with dynamic packing nuts to energize the dynamic packings into dynamic sealing engagement with the plungers.

12 . The method of claim 10 , wherein energizing the respective static packing comprises engaging an atmospheric side of the static packing corresponding to the identified plunger opposite the pressure side with a static packing nut.

13 . The method of claim 12 , wherein engaging with the static packing nut comprises threading the static packing nut into a dynamic packing nut using a motor.

14 . The method of claim 10 , wherein energizing the respective static packing comprises engaging an atmospheric side of the static packing corresponding to the identified plunger opposite the pressure side with an independently operable retainer.

15 . The method of claim 10 , further comprising engaging a dynamic packing nut with the fluid end and wherein energizing the respective static packing comprises engaging an atmospheric side of the static packing corresponding to the identified plunger opposite the pressure side with an actuator of the dynamic static packing nut.

16 . A fluid end for a reciprocating pump system comprising:

a body;

a plurality of plungers, each plunger reciprocable within a corresponding bore in the body;

for each plunger, a dynamic packing disposed in the bore around the plunger and configured to be energized into dynamic sealing engagement around the plunger against pressure from a pressure side;

for each plunger, a dynamic packing nut engageable an atmospheric side of the dynamic packing opposite the pressure side to energize the dynamic packing; and

a static packing in each dynamic packing nut configured to be energized by mechanical force into static sealing engagement around the plunger against pressure from a pressure side,

wherein when one of the plungers is being reciprocated, the dynamic packing corresponding to that plunger is energized by the dynamic packing nut and the static packing corresponding to that plunger is deenergized, and

wherein when one of the plungers is no longer being reciprocated, the static packing corresponding to that plunger is energized into static sealing engagement with the plunger.

17 . The fluid end of claim 16 , further comprising, for each plunger, a static packing nut engageable with the dynamic packing nut corresponding to that plunger and an atmospheric side of the static packing corresponding to that plunger opposite the pressure side to energize the static packing.

18 . The fluid end of claim 16 , further comprising, for each plunger, a retainer independently operable to engage an atmospheric side of the static packing corresponding to that plunger opposite the pressure side to energize the static packing.

19 . The fluid end of claim 16 , wherein, for each plunger, the dynamic packing nut corresponding to that plunger comprises an actuator operable to engage an atmospheric side of the static packing corresponding to that plunger opposite the pressure side to energize the static packing for that plunger.

20 . The fluid end of claim 16 , wherein, for each plunger, the static packing nut is engageable with the dynamic packing nut corresponding to that plunger by being threaded into the dynamic packing nut using a motor.