Abstract: A multi-port metering pump assembly includes a manifold coupled to a metering pump. The manifold defines a central passage in fluid communication with a plurality of intermediate passages defined in the manifold. The manifold includes a plurality of outer passages. Each intermediate passage provides fluid communication between the central passage and a corresponding outer passage. A plurality of valves is coupled to the manifold. Each valve of the plurality of valves is located between an intermediate passage and a corresponding outer passage, and is configured to enable or prevent passage of fluid between a corresponding intermediate passage of the plurality of intermediate passages and a corresponding outer passage. The multi-port metering pump assembly also includes an electronic controller coupled to the plurality of valves, the electronic controller having an associated electronic interface and being programmable to selectively and independently open and close the valves of the plurality of valves.

Abstract: Reciprocating fluid pumps include a pump body including a cavity therein, a plunger located at least partially within the cavity, and a shift canister assembly disposed within the cavity. The shift canister assembly includes a sealing surface for forming a seal against the pump body. An area covered by the seal between the sealing surface and the pump body is less than about 75% of an outer cross-sectional area of the shift canister assembly. The shift canister assembly may include a shift canister and a shift canister cap attached thereto, the shift canister cap comprising the sealing surface. Reciprocating fluid pumps include a shift canister, a shift piston at least partially disposed within the shift canister, and a shift canister cap attached to the shift canister on a longitudinal end of the shift canister opposite the shift piston. Methods include forming such reciprocating pumps.