Abstract: A crankshaft assembly includes a crankshaft configured to be operatively coupled to prime mover and rotatable about a rotational axis. A crank pin is coupled to the crankshaft for rotation therewith about the rotational axis, the crank pin including an outer surface and a bore extending through the crank pin parallel to the rotational axis. The crank pin further includes a hole in fluid communication with the bore. The hole includes a first portion extending outward from the bore and a second portion coupled to and extending from the first portion and connected to the outer surface. The second portion is defined by a non-cylindrical shape in longitudinal cross-section. The hole further includes an inner fillet disposed at an interface between the first portion and the non-cylindrical portion, and an outer fillet disposed at an interface between the non-cylindrical portion and the outer surface.

Abstract: A reagent head has a housing, an inlet and an outlet. Check valves and other details are not shown for clarity. The reagent head may have a dish where a diaphragm may seat when in a fully forward position. The reagent head may be constructed primarily from a high-strength material, e.g. ductile iron, in a substrate layer. The reagent head may also comprise a polymer layer. The polymer-metal interface may incorporate key grooves to provide an increased surface area for the polymer-metal bond. The key grooves may be any shape which increases the bonding surface area. Certain key groove cross-sectional shapes, such as dovetails, will create an interlocking interface that may provide increase resistance to separation of the polymer layer from the substrate layer.

Abstract: In one embodiment of the disclosure, a dish insert may be installed in a pump head such that the dish insert may be removed from the reagent head side of the pump head. Port holes permit movement of hydraulic fluid through the dish insert. The dish insert may be affixed to the pump head by fasteners. The dish insert may include removal means. For example, removal holes may be provided wherein fasteners may be threaded until the fasteners “bottom out” on the pump head. In this way, fasteners may force the dish insert out of the mounted position by acting against the threads as a jack screw.