Abstract: Pivot valves have a valve seat and a valve closure mounted for pivoting movement through a closure chamber in a passage. The pivot valves may be selectively set in a check mode and an open mode. Flapper valves have a hydrofoil extending from a flapper. Valve assemblies comprise the pivot valves and flapper valves and have an open condition, a check condition, and a shut-off condition.

Abstract: Frac pumps have a fluid end and a fluid end block. The fluid end block has a plunger cylinder having a primary axis, a suction bore having a primary axis, a discharge bore, and a pump chamber. The pump chamber is defined by the intersection of the plunger cylinder, the suction bore, and the discharge bore. The fluid end block has a cylindrical portion extending along the primary axis of the suction bore. The cylindrical portion has a diameter greater than the diameter of the plunger cylinder. The pump chamber also has a ridge that extends radially inward from the walls of the pump chamber in a plane normal to the suction bore primary axis.

Abstract: Dual path control fittings have a fitting body and a cylindrical plunger. The fitting body has a cylindrical bore, a first conduit, and a second conduit. The cylindrical bore provides a first inlet and an opening. The first conduit provides a second inlet. The second conduit provides an outlet. The cylindrical plunger is mounted for reciprocation in the bore and has a first conduit and a second conduit. The first conduit extends from one end of the plunger to a port on the circumference of the plunger. The second conduit extends transversely across the plunger. The plunger has a first position in which the port is aligned with the second fitting body conduit to provide a first path and a second position in which the plunger second conduit is aligned with the fitting body first and second conduits to provide a second path.