Offset valve bore in a reciprocating pump

A reciprocating pump assembly comprising:

• a crankshaft housing;
• and
• a fluid end connected to the crankshaft housing, the fluid end comprising:
• at least three cylinder chambers;
• at least three respective plunger bores in fluid communication with a respective cylinder chamber, each plunger bore receiving a reciprocating plunger, each plunger bore having a plunger bore axis, the plunger bores being arranged across the fluid end to define a central plunger bore and lateral plunger bores located on either side of the central plunger bore, the respective plunger bore axes of the lateral plunger bores defining a first distance therebetween;
• at least three respective suction valve bores in fluid communication with the cylinder chambers, each suction valve bore for receiving a suction valve and having a valve bore axis, the suction valve bores being arranged across the fluid end to define a central suction valve bore and lateral suction valve bores located on either side of the central suction valve bore;
• and
• at least three respective discharge valve bores in fluid communication with the cylinder chambers, each discharge valve bore for receiving a discharge valve and having a valve bore axis, the discharge valve bores being arranged across the fluid end to define a central discharge valve bore and lateral discharge valve bores located on either side of the central discharge valve bore;
• wherein each of the plunger bores, the suction valve bores, and the discharge valve bores intersects with its respective cylinder chamber;
• wherein the central suction and discharge valve bores are not offset from the central plunger bore and thus the respective valve bore axes of the central suction valve bore and the central discharge valve bore are co-axial with each other and intersect the plunger bore axis of the central plunger bore;
• wherein at least one of the valve bore axes of at least one of the lateral suction and discharge valve bores that is in fluid communication with the lateral plunger bore located on one side of the central plunger bore is inwardly offset within its respective lateral cylinder chamber so that:
• a second distance is defined between the at least one valve bore axis of the at least one of the lateral suction and discharge valve bores and the corresponding valve bore axis of the lateral suction or discharge valve bore that is in fluid communication with the lateral plunger bore located on the other side of the central plunger bore, the second distance is less than the first distance, and
• the at least one valve bore axis of the at least one of the lateral suction and discharge valve bores is positioned between the respective plunger bore axes of the central plunger bore and the lateral plunger bore located on the one side of the central plunger bore;
• and
• wherein the inward offset is located at least at an intersection of the lateral plunger bore, the lateral cylinder chamber and the at least one of the lateral suction and discharge valve bores.

A fluid end for a multiple reciprocating pump assembly, the fluid end comprising:

• at least three cylinder chambers;
• at least three respective plunger bores in fluid communication with a respective cylinder chamber, each plunger bore receiving a reciprocating plunger, each plunger bore having a plunger bore axis, the plunger bores being arranged across the fluid end to define a central plunger bore and lateral plunger bores located on either side of the central plunger bore;
• at least three respective suction valve bores in fluid communication with the cylinder chambers, each suction valve bore for receiving a suction valve and having a valve bore axis, the suction valve bores being arranged across the fluid end to define a central suction valve bore and lateral suction valve bores located on either side of the central suction valve bore;
• and
• at least three respective discharge valve bores in fluid communication with the cylinder chambers, each discharge valve bore for receiving a discharge valve and having a valve bore axis, the discharge valve bores being arranged across the fluid end to define a central discharge valve bore and lateral discharge valve bores located on either side of the central discharge valve bore;
• wherein a first distance is defined between the respective plunger bore axes of the central plunger bore and the lateral plunger bore located on one side of the central plunger bore;
• wherein each of the plunger bores, the suction valve bores, and the discharge valve bores intersects with its respective cylinder chamber;
• wherein at least one of the valve bore axes of at least one of the lateral suction and discharge valve bores that is in fluid communication with the lateral plunger bore located on the one side of the central plunger bore is inwardly offset within its respective lateral cylinder chamber so that:
• a second distance is defined between the at least one valve bore axis of the at least one of the lateral suction and discharge valve bores and the plunger bore axis of the central plunger bore;
• the second distance is less than the first distance, and
• the at least one valve bore axis of the at least one of the lateral suction and discharge valve bores is positioned between the respective plunger bore axes of the central plunger bore and the lateral plunger bore located on the one side of the central plunger bore;
• and
• wherein the inward offset is located at least at an intersection of the lateral plunger bore, the lateral cylinder chamber and the at least one of the lateral suction and discharge valve bores.