How To Ensure Effective Primary Well Control

Primary well control is the most important barrier while drilling and completing any wells so it is imperative to ensure that the primary well control is effectively maintained.

When various precautions and procedures have been followed, effective primary well control can be achieved. These procedures can be seen below;

Tripping Procedures

 Using a trip sheet (an accurate log), it is possible to maintain tripping both in and out of the well. A trip sheet can help to record the volume of mud that not only enters the well but also that is displaced when tripping. During tripping, the changes in mud volume can be measured using a calibrated trip tank.

For any steel removed, a specific amount of mud is entered into the well when the tripping pipe or drill collars from the hole. To ensure proper well monitoring, tripping may need to be stopped whenever the volume of removed steel significantly outweighs the volume of mud required. After stopping, consideration should also be made towards returning back to bottom in order to condition the mud (and find the cause of the issue). At all times, the drill floor should have the required crossover subs and a full opening safety valve readily available. Continue reading

Categories of Well Control

Well control can be categorized into three main categories which are Primary Well Control, Secondary Well Control and Tertiary Well Control. The details are shown below;

Primary Well Control

Primary Well Control is hydrostatic pressureprovided by drilling fluid more than formation pressure but less than fracture gradient while drilling. If hydrostatic pressure is less than reservoir pressure, reservoir fluid may influx into wellbore. This situation is called “Loss Primary Well Control”. Typically, slightly overbalance of hydrostatic pressure over reservoir pressure is normally desired. The basic of maintaining primary well control is to maintain hydrostatic pressure that is heavy enough to overcome formation pressure but not fracture formations.

Figure 1 - Drilling Fluid

Figure 1 – Drilling Fluid

Not only is hydrostatic pressure more than formation pressure, but also hydrostatic pressure must not exceed fracture gradient. If mud in hole is too heavy, it will cause a broken wellbore, that will result in loss circulation problem (partially lost or total lost circulation). When fluid is losing into formation, mud level in well bore will be decreased that will cause reduction in hydrostatic pressure. For the worst case scenario, hydrostatic pressure is less than formation pressure therefore wellbore influx (kick) will enter into wellbore. Continue reading

Review Well Control Method Presentation by Wild Well Control

Wild Well Control is one of the best well control specialist companies in the world. The company not only provide well control and engineering services to the company’s customers, it also provides free technical knowledge to the public such as Wild Well Control Technical Book that you can download it for free.  Today, we would like to review one of the most useful presentation which is “Well Control Methods” presentation. After you read the review and you like it, we also provide download link for you at the end. Thank Wild Well Control for great contribution to oil and gas industry.

Well Control Methods by Wild Well Control

Well Control Methods by Wild Well Control, Wild Well Control (2017)

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IWCF Drilling Calculation Part 1 – 3 Review

International Well Control Forum (IWCF) has provided useful learning material, which is IWCF Drilling Calculation Part 1 – 3, to drilling people. We will review all of them and see the content inside. Additionally, these ebooks are available to download from IWCF website. Thanks for their contribution to drilling industry.

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Well Control

This page contains well control contents in this site.


Basic Calculation Related to Well Control

Adjusted maximum allowable shut-in casing pressure
Brine weight with temperature correction
Calculate Annular Capacity
Calculate Annular Pressure Loss
Calculate Equivalent Circulation Density (ECD) with complex engineering equations
Calculate Influx Height
Calculate inner capacity of open hole/inside cylindrical objects
Calculate Pressure Gradient and Convert Pressure Gradient
Calculate Specific Gravity (SG) in oilfield unit
Convert Pressure into Equivalent Mud Weight
Convert specific gravity to mud weight (ppg and lb/ft3) and pressure gradient (psi/ft)
Corrected D Exponent Calculation
D Exponent Calculation
Determine height of light weight spot pill to balance formation pressure
Determine the actual gas migration rate
Drill pipe pulled to lose hydrostatic pressure
Equivalent Circulating Density (ECD) in ppg
Equivalent Circulating Density (ECD) Using Yield Point for MW less than 13 ppg
Equivalent Circulating Density (ECD) Using Yield Point for MW More than 13 ppg
Estimate gas migration rate in a shut in well
Estimate Type of Influx (kick)
Formation Integrity Test (FIT) Procedure and Calculation
Formation Pressure from Kick Analysis
How does the 0.052 constant come from?
Hydraulic Horse Power (HPP) Calculation
Hydrostatic Pressure (HP) Decrease When POOH
Hydrostatic Pressure Calculation
Hydrostatic Pressure Loss Due to Gas Cut Mud
Kick Tolerance Calculation
Kill Weight Mud
Leak Off Test (Procedures and Calcuation)
Loss of Hydrostatic Pressure due to Lost Return
Maximum pit gain from gas kick in water based mud
Maximum Surface Pressure from Gas Influx in Water Based Mud
Pipe Displacement Calculation
Pump Output Calculation for Duplex Pump and Triplex Pump
Pump pressure and pump stroke relationship
Temperature Conversion Formulas
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