Multi-bolt clamshell retainer for wristpin on rod pump unit
AssigneeTRC Services, Inc.
InventorsDarius J. Yakimchuk, Robert G. McDonald
Life of this patent
Estimating the term…
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.
Claims28
An assembly connecting a pitman arm to a slot in a crank arm of a reciprocating pump unit, the crank arm having first and second sides, the pitman arm disposed on the first side and having a bearing, the assembly comprising:
- a pin having a proximal end and a distal end, the pin having the bearing of the pitman arm configured to rotate about the proximal end, the pin extending from the bearing of the pitman arm and positioned in the slot of the crank arm, the distal end of the pin extending from the second side of the crank arm, the distal end defining an external shouldered profile;
- a clamp clamped on the distal end of the pin, the clamp having a front face, a back face, and an internal shoulder profile, the clamp defining holes extending through the clamp from the back face to the front face, the front face positioned adjacent to the second side of the crank arm, the internal shouldered profile engaged with the external shouldered profile on the distal end of the pin;
- one or more spacer washers positioned on the distal end of the pin between the front face of the clamp and the second side of the crank arm;
- and
- a plurality of tensioning bolts threaded in the holes extending through the clamp from the back face to the front face, ends of the tensioning bolts engaged against an outermost one of the one or more spacer washers,
- wherein the clamp, the tensioning bolts, and the one or more spacer washers are configured to hold the pin in place relative to the slot of the crank arm;
- and
- wherein the tensioning bolts are adjustably threaded and the one or more spacer washers are selectively positioned to adjust tensioning of the pin relative to the crank arm.
A kit to connect a pitman arm to a slot in a crank arm of a reciprocating pump unit, the crank arm having first and second sides, the pitman arm disposed on the first side of the crank arm and having a bearing, the kit comprising:
- a pin having a proximal end and a distal end, the pin having the bearing of the pitman arm configured to rotate about the proximal end, the pin configured to extend from the bearing of the pitman arm and configured to position in the slot of the crank arm, the distal end of the pin being configured to extend from the second side of the crank arm, the distal end defining an external shouldered profile;
- a clamp configured to clamp on the distal end of the pin, the clamp having a front face, a back face, and an internal shoulder profile, the clamp defining holes extending through the clamp from the back face to the front face, the front face configured to position adjacent to the second side of the crank arm, the internal shouldered profile being configured to engage the external shouldered profile on the distal end of the pin;
- and
- a plurality of spacer washers, one or more of the spacer washers are configured to position on the distal end of the pin between the front face of the clamp and the second side of the crank arm;
- and
- a plurality of tensioning bolts threaded in the holes extending through the clamp from the back face to the front face, ends of the tensioning bolts engaged against an outermost one of the one or more spacer washers positioned on the distal end of the pin,
- wherein the clamp, the tensioning bolts, and the one or more spacer washers are configured to hold the pin in place relative to the slot of the crank arm;
- and
- wherein the tensioning bolts are adjustably threaded and the one or more spacer washers are selectively positioned to adjust tensioning of the pin relative to the crank arm.
A method to connect a pitman arm to a slot in a crank arm of a reciprocating pump unit, the method comprising:
- positioning a pin extending from a bearing of the pitman arm on a first side of the crank arm into the slot in the crank arm, the pin having a proximal end and a distal end, the proximal end having the bearing of the pitman arm configured to rotate thereabout, the distal end of the pin extending from a second side of the crank arm;
- clamping a clamp on the distal end of the pin exposed on the second side of the crank arm by engaging an internal shouldered profile on the clamp to an external shouldered profile on the distal end of the pin;
- and
- holding the pin in place relative to the slot of the crank arm and tensioning the pin relative to the crank arm by:
- selectively positioning one or more spacer washers on the distal end of the pin between the second side of the crank arm and a front face of the clamp;
- and
- adjustably threading a plurality of tensioning bolts extending from a back face of the clamp to the front face to engage ends of the tensioning bolts against an outermost one of the one or more spacer washers.
Dependencies are inferred from the claim text.