Artificial Lift

Tubing leaks have historically accounted for nearly half of the failures in the Hess Bakken wells. The root cause of these leaks is coupling on tubing wear; the non-metallic guides wear out, which results in spray metal couplings contacting the production tubing. To address this problem, the company installed ToughMet® 3 TS95 sucker rod couplings in over 650 wells, reducing the failure rate in the...

Gas lift is becoming a popular form of artificial lift in the Permian Basin for long horizontal wells that make high gas rates. Unfortunately the decline curves on most horizontal wells are not ideal. As the rates and pressure quickly drop gas lift starts to become inefficient and we are forced to make artificial lift changes in order to preserve base production. Rod pumps have always been the end...

The most common form of artificial lift is sucker-rod pumping.  One of the main elements of rod lift system design is the selection of a downhole pump.  This study examines the various factors that affect the selection and design of downhole rod pumps. Downhole rod pumps are made up of five main components: barrel, plunger, balls and seats, seating assembly, and valve rod or pull tube....

Automation of rod pumping systems has been a part of the oil and gas industry for over 65 years.  Starting with time clocks in the 1950s, the invention of the pump-off controller in the 60s, and variable speed drives in the early 2000s, the amount of technology available to both control and analyze the system has increased and improved drastically. Several of the driving factors to automate...

Rod wear and corrosion have a complex relationship that is often misunderstood of oversimplified.  This paper provides a technical framework and provides empirical evidence of principles that clarify this complex relationship.  In particular, this paper will review stress levels and metal failure mechanisms that dispel many commonly held beliefs.  A better understanding of these principles will...

Downhole sucker rod pump clearance changes from shop conditions to bottom hole conditions due to bottomhole pressure and temperature that the pump components are subjected to. Presented here are equations to estimate the change in dimensions of the plunger and barrel of top and bottom hold down pumps at bottomhole pressure and temperature conditions. The approach uses one equation for cylinder...

Pumping wells hard involves a tradeoff between operating cost and production. Increased idle time or holding additional back pressure on the reservoir can decrease production but pumping a well harder will likely increase failure frequency. The existing reservoir pressure has a significant impact on the potential change in production.  Pump-Off Controllers (POCs) are used to regulate run time on...

New unconventional wells have been a huge challenge for ESPs in the Permian Basin because in horizontal wells with high-formation GORs or GLRs, the pumped fluid can cause issues such as gas interference, gas locking, short run life, low production, poor energy efficiency, increased failure rates, shutdowns, so forth. A major problem is gas presence around the ESPs, it causes the motor to rapidly...

America needs energy. Good techniques (Vogel’s Method and Constant PI) exist for estimating production from wells. These are phrased in terms of pressure. Pressure is not easy to measure especially in deep gassy wells. Fluid level is a logical remedy for the problem and can be measured at virtually any depth. But this creates the need for a method for deriving pressure (PIP) from fluid level...

Historically as many as 30% of bottom hold down pumps have been stuck. This can result in extra cost associated with pulling tubing on pump repairs or rod failures. This paper focuses on efforts with various tools and techniques that have been used to lessen the number of pumps stuck in tubing.