Abstract: A valve has a body having a rotatable valve element. A drive mechanism has a drive input member and a drive output member that are coupled to the valve element for rotating the valve element. A shear member is operatively located within the drive mechanism between the drive input member and the drive output member for shearing in the event the force to rotate the valve element is excessive. The valve has indicia indicating open and closed positions for the valve element. An indicator is mounted to output drive member to properly align with the indicia regardless whether the shear member has sheared or not.

Abstract: A valve has a body having a rotatable valve element. A drive mechanism has a drive input member and a drive output member that are coupled to the valve element for rotating the valve element. A shear member is operatively located within the drive mechanism between the drive input member and the drive output member for shearing in the event the force to rotate the valve element is excessive. The valve has indicia indicating open and closed positions for the valve element. An indicator is mounted to output drive member to properly align with the indicia regardless whether the shear member has sheared or not.

Abstract: A valve has a body having a rotatable valve element. A drive mechanism has a drive input member and a drive output member that are coupled to the valve element for rotating the valve element. A shear member is operatively located within the drive mechanism between the drive input member and the drive output member for shearing in the event the force to rotate the valve element is excessive. The valve has indicia indicating open and closed positions for the valve element. An indicator is mounted to output drive member to properly align with the indicia regardless whether the shear member has sheared or not.

Abstract: A pressure relief system for a reciprocating pumping system that deintensifies pressure from the pumping system and controls relief operation with the deintensified pressure. The relief system includes a relief valve connected to the pumping system and a control system that selectively opens the relief valve when an overpressure is sensed in the pumping system. To keep the relief valve in a closed position, the control system maintains a backpressure on the relief valve using the deintensified pressure. A dump valve in the control system selectively vents the backpressure so the relief valve can open. A charging system can be used for charging the control system and for reseating the relief valve.