Sucker Rod Pumping

Sucker Rod Pumping

What is Sucker Rod?

Sucker rod pumping, also known as Beam Pumping, mechanically lifts oil from the bottom hole to the surface. It is efficient, simple, and easy for field personnel to operate.

SR Pump Equipment

Surface Equipment Includes:

• Prime Mover: Drives the system, typically an electric motor or gas engine.
• Gear Reducer/Gearbox: Reduces the prime mover's speed and increases torque.
• Pumping Unit: Converts rotary motion to reciprocating motion using a walking beam.
• Polished Rod: Connects the walking beam to the sucker-rod string, sealing the wellhead.
• Wellhead Assembly: Contains a stuffing box for sealing and a pumping tee to direct fluids into the flowline via a check valve.

Downhole Equipment Includes:

• Rod String: Sucker rods inside the tubing link the surface drive to the subsurface pump.
• Pump Plunger: Moves with the rod string, featuring a traveling valve that lifts liquid on the upstroke.
• Pump Barrel (Working Barrel): The stationary cylinder with a standing valve for fluid entry during the upstroke.

Types of Beam Pumps

Beam pump geometries fall into two main categories:

1. Class-I Lever System:
   • Description: Rear-mounted speed reducer with the fulcrum at mid-beam.
   • Example: Conventional pumping units.
2. Class-II Lever System:
   • Description: Push-up geometry with a front-mounted speed reducer and fulcrum at the beam's rear.
   • Examples: Air-balanced and Lufkin Mark II units.

Additionally, Lufkin offers three types:

• Conventional
• Mark II
• Air Balanced

Subsurface Pump Types

Rod-drawn pumps are categorized into three types:

1. Tubing Pumps:
   • Installed within the well's tubing string.
2. Insert (Rod) Pumps:
   • Inserted into the well tubing to facilitate pumping.
3. Casing Pumps:
   • Larger versions of insert pumps, installed in the casing.

Advantages of Sucker Rod Pump

• System Efficiency: High efficiency in operations.
• Slim Holes: Suitable for wells with limited space.
• Multiple Completions: Handles multiple production zones.
• High-Temperature Operations: Effective in high-temperature environments.
• Viscous Oils: Pumps thick, viscous oil efficiently.
• Economical Maintenance: Cost-effective to repair and service.
• Positive Displacement: Strong drawdown capabilities.
• Corrosion-Resistant Materials: Reduces corrosion concerns.
• Flexibility: Adjust production through stroke length and speed.
• High Salvage Value: Valuable surface and downhole equipment.

Disadvantages of Beam Pumping

• Excessive Friction: Issues in crooked or deviated wells.
• Solid-Sensitive Problems: Struggles with wells containing solids.
• Low Efficiency in Gassy Wells: Less effective where gas is present.
• Limited Depth: Depth limited by rod capacity.
• No Offshore Application: Not suitable for offshore operations.