Reciprocating rod pumping unit

A reciprocating rod pumping unit, comprising:

• a tower;
• a counterweight assembly movable along the tower;
• a drum connected to an upper end of the tower and rotatable relative thereto;
• a belt having a first end connected to the counterweight assembly, extending over the drum, and having a second end connectable to a rod string;
• a prime mover for reciprocating the counterweight assembly along the tower;
• a sensor for detecting a condition of the pumping unit, wherein the sensor is a speed sensor for detecting a speed of the belt;
• and
• a controller in communication with the sensor and operable to cause the counterweight assembly to stop in response to the detected condition, wherein the controller is configured to calculate an acceleration of the belt using the speed measured by the speed sensor.

A reciprocating rod pumping unit, comprising:

• a tower;
• a counterweight assembly movable along the tower;
• a drum connected to an upper end of the tower and rotatable relative thereto;
• a belt having a first end connected to the counterweight assembly, extending over the drum, and having a second end connectable to a rod string;
• a prime mover for reciprocating the counterweight assembly along the tower;
• a brake system for halting movement of the counterweight assembly;
• a lubrication system for applying lubricant to at least one of a chain, a bearing, and combinations thereof;
• at least one of:
• a lubrication sensor for detecting an amount of lubricant in the lubrication system;
• a pressure sensor for detecting a pressure in the lubrication system;
• and
• a flow meter for measuring a flow rate of the lubricant;
• and
• a controller in communication with the at least one of the lubrication sensor, the pressure sensor, and the flow meter, and operable to activate the brake system in response to detection of a faulty condition of the lubrication system.

A reciprocating rod pumping unit, comprising:

• a tower;
• a counterweight assembly movable along the tower;
• a drum connected to an upper end of the tower and rotatable relative thereto;
• a belt having a first end connected to the counterweight assembly, extending over the drum, and having a second end connectable to a rod string;
• a prime mover for reciprocating the counterweight assembly along the tower;
• a sensor for detecting a condition of the pumping unit selected from the group consisting of:
• a speed sensor for detecting a speed of the belt;
• a cycle sensor for detecting a cycle of the belt;
• a load sensor for detecting a change in load on the drum;
• a belt alignment sensor for detecting an alignment of the belt;
• a vibration sensor for detecting a vibration of the tower;
• and
• combinations thereof;
• a gearbox;
• a brake system for halting movement of the counterweight assembly, the brake system having:
• a disk torsionally coupled to the gearbox;
• a piston disposed in a cylinder;
• a caliper connected to the piston;
• and
• a brake pad mounted to the caliper and movable by the piston between an engaged position and a disengaged position relative to the disk;
• and
• a bias member configured to bias the piston and the brake pad toward the engaged position;
• and
• a controller in communication with the sensor and operable to activate the brake system in response to detection of the faulty condition of the pumping unit.