Abstract: A fracturing pump system includes a fluid end having a cylinder and a piston movable to pressurize fluid in the cylinder. The cylinder has at least one cylinder sidewall, packing located to prevent fluid from leaking between the piston and the cylinder sidewall, and a hydraulically-driven assembly configured to apply variable amounts of pressure on the packing.

Abstract: According to an embodiment, a pump includes a power end, and a fluid end. A sliding plate extends from the power end, and a distal end of the sliding plate has engaging structure. The fluid end has complementary engaging structure for slidably mating with the engaging structure as the fluid end is raised or lowered relative to the power end. A locking plate is provided for preventing disengagement of the complementary engaging structure and the engaging structure.