Tag Archives: Gas handling device

ESP submersible pumping system

By | | , ,
Leave a comment

The ESP submersible pumping system consists of both downhole and surface components. The surface components are transformers, motor controllers, junction box and wellhead.

The wellhead accommodates the passage of the power cable from the surface to the wellbore.

The main down-hole components are the motor, seal, pump, and cable. Additional accessory equipment may include the gas separators, check and drain valves, cable bands and protectors, and downhole sensors.

Technologies, types, recommended practices and selection criteria of each compound of the ESP pumping system are discussed in the following list of 22 posts.

ESP Pump:

01- Submersible Pump System Overview

02- Centrifugal Pump ( ESP Pump)

03- ESP: Pump Stage

04- Pump impeller types

05- Pump Performance Curves – part 01

06- Pump Performance Curves – part 02

07- Pump Construction: Compression Pump vs. Floater Pump

08- Pump Shaft

Pump Intake:

09- Pump Intake

10- ESP Motor Shroud: Applications, Configurations and Selection Criteria

11- ESP: Gas handling device

Seal Section:

12- Motor Seal

ESP Motor:

13- ESP Motor

ESP Cable:

14- ESP Cable

15- Power losses in cables

16- Motor Lead Extension

17- ESP Power Cable Accessories

Motor Controller:

18- ESP Motor Switchboard

19- Variable Frequency Drive Basics

Transformer:

20- Introduction to transformer: How it works?

Wellhead Equipment:

21- Wellhead Equipment for ESP

Accessory Equipment:

22- ESP Accessory Equipment

ESP design – Step 6: Optimum Size of Compounds

By | |
Leave a comment

ESP compounds have different sizes and can be assembled in a variety of combinations. These combinations must be carefully determined to operate the ESP with production requirement, downhole conditions, material strength and temperature limits, etc. to select the optimum size of compounds.

Pump:

To determine the required number of stages of the pump to produce the anticipated capacity; just divide the Total Dynamic Head (TDH) by the Head developed by Stage.

Refer to the article “ESP design – Step 4: Total Dynamic Head” to review how the TDH is calculated.

The Head developed per stage is deducted from the published performance curve which shows the discharge head developed by the pump. It is an experimental curve given by the manufacturer and obtained with fresh water at 60 F under controlled conditions detailed in API R11 S2. Refer to the articles “Pump Performance Curves – part 01” and “Pump Performance Curves – part 02” for more details.

Once calculated, divide the TDH by the Head developed per stage to get the Total Number of Stages required to produce the anticipated capacity.

Total Stages = TDH / [(Head / stage)]

Continue reading →

Motor Seal

By | | , ,
Leave a comment

The Motor seal is installed below the intake and above the electric motor. It is also named: Equalizer, balance chamber, or Protector. Seal section types, functions, components, and applications are detailed in this article.

In addition to the main function of transferring the motor torque to the pump shaft, the seal section performs four primary functions (Equalization, Expansion, Isolation, & “Aabsorbsion”):

  • Equalizes the pressure in the wellbore with the pressure inside the motor,
  • Provides area for motor oil expansion volume (induced by temperature changes in the motor),
  • Isolates the well fluid from the clean motor oil,
  • Absorbs the pump shaft thrust load (it houses the thrust bearing that carries the axial thrust developed by the pump, it can either be upthrust or downthrust, depending on the pumping conditions – obviously, for fixed impeller type only).

                        

PS: The motor, pump and seal are often submerged below several thousand feet of fluid. The seal section allows the pressure in the motor and the annulus to equalize, so that there is very little pressure across the shaft seals or the pothead connection.

PS: When selecting the protector, we need to be certain that the protector shaft is capable of delivering the full torque required without exceeding its yield strength which could result in a broken shaft.

Continue reading →

ESP: Gas handling device

By | | , ,
Leave a comment

Gas  handling  devices  may  be  a  better  alternative  for  wells  prone  to  high  free  gas, slugging, foams and emulsions. These are essentially centrifugal pumps with large stages, mixed  (or  axial)  impellers,  large  vane  openings,  steep  vane  exit  angles  and  sometimes include multiple  vanes. 

Instead of separating, their purpose is to break large gas bubble into smaller ones thereby reducing the risk of gas locking and making it easier for gas to be re-absorbed into solution, and to homogenize the gas with liquid phases, prior to entering the pump intake.

An additional benefit of gas handlers is, because more gas is retained in the flow stream, this gas is then available to help lift fluids in the tubing above the ESP discharge head thereby reducing hydraulic horsepower requirements.

Applications: A Gas Handler is generally considered if the Free Gas Percentage at the intake of the pump is from 30% to 60% by volume.

Continue reading →