Abstract: An assembly connects a pitman arm to a slot in a crank arm of a pumping unit. A pin extends from the pitman arm disposed on a first side of the crank arm. The pin is disposed in the slot of the crank arm and has a distal end exposed on a second side of the crank arm. The distal end defines an external shouldered profile. A clamp is positioned on the distal end of the pin. The clamp has an internal shouldered profile, which is configured to engage the external shouldered profile on the pin. One or more spacers are disposed on the clamp and are configured to adjustably extend from the clamp toward the second side of the crank arm.

Abstract: An assembly is used to connect an equalizer bar to a walking beam of a reciprocating pump unit. The walking beam has a bearing shaft having cylindrical ends. Brackets attached to the equalizer bar define slots, each having a hooked section and having a base section. The hooked sections are configured to rest against the cylindrical ends of the bearing shaft. The base sections of the slots oppose the hooked sections at a gap from the cylindrical ends of the bearing shaft. Wedges are configured to position in the slots between the bases and the cylindrical ends of the bearing shaft.

Abstract: A horsehead is used on a walking beam of a reciprocating pump unit. The horsehead includes side plates, a face, tabs, and brace plates. The side plates are spaced apart, and the face affixed to front, arced edges of the side plates. The face defines a split therein extending from a bottom end toward a top end, and the tabs are affixed to the face across the split. The face thereby defines two runner surfaces. A fixture at the top end of the face can be used for connection to a bridle of the pump unit. The brace plates are connected in the space between the side plates and are arranged in a lattice structure. Preferably, the brace plates include cutouts to reduce weight.

Abstract: A surface unit can operate as a longer stroke unit to reciprocate a rod string for a downhole pump in a well. The unit has an end weight that gives the walking beam and head a zero-imbalance about the unit's fulcrum point. The unit can also operate as a phased unit in which the counterweights of the crank arms lag behind the pivot connection and/or the crank point is disposed rearward of the equalizer bearing of the walking beam.