Packing for a well service pump

1. A packing arrangement for a fluid end of a reciprocating pump, the packing arrangement received within a packing box and arranged to form a seal with a plunger, the packing arrangement comprising:

a first ring positioned at a high pressure end of the packing box;

a last ring positioned at a low pressure end of the packing box; and

a header ring disposed between the first ring and the last ring, the header ring including an inner surface that is non-cylindrical and arranged to contact the plunger and a female chevron portion facing the high pressure end of the packing box.

2. The packing arrangement of claim 1 , wherein the first ring comprises a cylindrical inner surface in contact with the plunger, a female chevron portion facing the high pressure end of the packing box and a male chevron portion facing the low pressure end of the packing box.

3. The packing arrangement of claim 1 , wherein the header ring comprises a male chevron portion facing the low pressure end of the packing box.

4. The packing arrangement of claim 3 , wherein the male chevron portion of the header ring includes a knob portion that extends toward the low pressure end of the packing box.

5. The packing arrangement of claim 4 , further comprising a pressure ring disposed downstream of the header ring, the pressure ring including a female chevron portion that engages the male chevron portion of the header ring, the pressure ring further comprising an aperture sized to receive the knob portion.

6. The packing arrangement of claim 5 , further comprising a packing nut threadably engaged with the fluid end and movable to compress the first ring, the header ring, the pressure ring, and the last ring.

7. The packing arrangement of claim 1 , wherein the female chevron portion of the header ring defines an included angle between 90 degrees and 130 degrees.

8. A packing arrangement for a fluid end of a reciprocating pump, the packing arrangement received within a packing box and arranged to form a seal with a plunger, the packing arrangement comprising:

a junk ring positioned at a high pressure end of the packing box;

a first support ring positioned downstream of and abutting the junk ring; a first pressure ring positioned downstream of and abutting the first support ring;

a header ring positioned downstream of and abutting the first pressure ring, the header ring including an inner surface that is non-cylindrical and that is arranged to abut the plunger and a female chevron portion facing the high pressure end of the packing box;

a second pressure ring positioned downstream of and abutting the header ring; a second support ring positioned downstream of and abutting the second pressure ring;

a lantern ring positioned downstream of and abutting the second support ring; and a packing nut threadably engaged with the fluid end and movable to compress the junk ring, the first support ring, the first pressure ring, the header ring, the second pressure ring, the second support ring, and the lantern ring within the packing box,

wherein the packing arrangement is progressively harder from the first support ring to the high pressure end.

9. The packing arrangement of claim 8 , wherein the junk ring comprises a planar surface facing the high pressure end of the packing box and a male chevron portion facing a low pressure end of the packing box.

10. The packing arrangement of claim 9 , wherein the first support ring, the second support ring, the first pressure ring, and the second support ring are chevron shaped such that each includes a female chevron portion that faces the high pressure end of the packing box and a male chevron portion that faces the low pressure end of the packing box.

11. The packing arrangement of claim 8 , wherein the header ring comprises a female chevron portion that faces the high pressure end of the packing box and a male chevron portion that faces the low pressure end of the packing box.

12. The packing arrangement of claim 11 , wherein the male chevron portion of the header ring includes a knob portion that extends toward the low pressure end of the packing box.

13. The packing arrangement of claim 12 , wherein the second pressure ring includes an aperture sized to receive the knob portion.

14. The packing arrangement of claim 11 , wherein the female chevron portion of the header ring defines an included angle between 90 degrees and 130 degrees.

15. The packing arrangement of claim 14 , wherein the packing arrangement is progressively harder from the second support ring to the lantern ring.

16. A packing arrangement for a fluid end of a reciprocating pump, the packing arrangement received within a packing box and arranged to form a seal with a plunger, the packing arrangement comprising:

a plurality of separate annular rings arranged in an abutting relationship with one another within the packing box;

a header ring disposed within the plurality of separate annular rings, the header ring including an inner surface that is non-cylindrical and that is arranged to abut the plunger, a high pressure side that is arranged in a female chevron shape, and a low pressure side opposite the high pressure side; and

a packing nut engaged with the fluid end and operable to compress the header ring and the plurality of separate annular rings within the packing box.

17. The packing arrangement of claim 16 , wherein the low pressure side of the header ring includes a male chevron portion that extends toward a low pressure end of the packing box.

18. The packing arrangement of claim 17 , wherein the male chevron portion of the header ring includes a knob portion that extends toward the low pressure end of the packing box.

19. The packing arrangement of claim 16 , wherein the high pressure side of the header ring defines an included angle between 90 degrees and 130 degrees.

20. The packing arrangement of claim 19 , wherein the included angle is 110 degrees.