Secondary control is the proper use of blowout prevention equipment to control the well. The Drilling Supervisor is responsible for ensuring all relevant Drilling Contractor and Service personnel are aware of the standard Company Operational Practices, including well control methods and kick prevention.

The time spent with the pipe out of the hole shall be minimised. Routine BOP repairs and slipping and cutting of the drill-line shall be done with pipe at the casing shoe.


Well Control during Logging Operations

Wireline BOPs are not normally used for open hole logging operations or cased hole operations where the Drilling BOPs are installed.  Exceptions to this rule are:

  • Open Hole logging operations…

Well Kill Using Wait and Weight Method (Balanced Method)

The “Wait and Weight” method is the method recommended, in some circumstances, for controlling an influx taken while drilling or circulating on bottom. When drillpipe (string) volume is greater than…

Well Control - Driller's Method

With this method, the well is killed in two circulations. During the first circulation: the influx is circulated out of the hole using the existing mud. Additional influx is prevented by adjusting the…

Well Control - Combined stripping and volumetric method

When the drillstring is partially or completely out of the hole and a kick is experienced, every effort should be made to safely return the bit to bottom whilst at the same time maintaining well…

Well Control - Bullheading

Bullheading. If normal well killing techniques with conventional circulation are not possible or will result in critical well control conditions, bullheading may be considered. Mud/influx are…

Non-conventional well control methods

Non-conventional well control methods

When the standard well control method (drillers' or weight and wait) are not suitable, alternative methods can be considered: Stripping, bullheading, volumetric, off-botton, no circulation, etc

1.…

Well Control - Balanced Mud Method

In this method the well is killed in one circulation. The kick is circulated out whilst mud of sufficient density to (over) balance the pore pressure is circulated in.

Mud with a density sufficient to…

Well Control - Deviated and Horizontal wells

All hydrostatic pressure-related calculations should be based on true vertical depth values. This means that the standpipe kill graph of a deviated well has a different curve as compared to the graph…

Bullheading

If normal well killing techniques are not possible or will result in critical well control conditions bullheading may be considered whereby mud/influx in displaced/squeezed back into the weakest open…

Complications during well control operations

Complications during well control operations Stopping the control operation, Plugged chokes, Change in circulating kill rate, Plugged bit nozzles, Kick caused by loss of circulation below production…

Problems Encountered During Well Control

Problems Encountered During Well Control

Conventional well killing procedures are based upon the basis that all of the well control equipment operates as designed and the wellbore is able to withstand the imposed pressures.

Mechanical…

Well Control - Recognizing a kick and action to be taken

Recognising a kick and need for immediate action.A kick occurs when the hydrostatic pressure of the mud column in the well is less than the pore pressure of a producing formation.Drilling breaks and…

Procedure and Calculation example for Change in Circulating Rate

Procedure and calculation example for Change in Circulating Rate while circulating an influx during a well control incident.

1. Calculate the average mud weight (Wav) in the string at the time pumping…

Well Control - Stripping Method

This article describes the keys elements for the stripping method for well control

Well Control - Kick whilst tripping

If an overbalance existed prior to pulling out of hole, then the only reasons for the well to flow are:·swabbing;·failure to keep the hole full;·losses induced by surge pressures.

Early detection of…

Kicks with Casing in the BOP Stack

Well control precautions to be used when running casing.

  • Change the rams to the casing size (on surface stack) and test the BOP bonnets.
  • Prepare a circulating head.
  • Ensure a cross-over from casing to…

Well Control - Slim Hole Drilling

Slim Hole Drilling which, for the purpose of well control, means hole sizes of 4 3/4" and smaller, will impose certain restrictions on well killing techniques and will require well planning to take…

Kicks with Drill Collars in the BOP Stack

The detection of a kick when the drill collars are in the BOP stack is a time of concern for the safety of the crew and the drilling unit as the normal methods of secondary control using the BOP’s may…

Well Control Procedure - While Tripping

To detect a kick while round tripping as early as possible, it shall be standard practice to use the trip tank at all times while tripping both into and out of the hole.

The Driller shall be…

Pressure at the top of a Gas Influx in the Annulus using the ‘Wait and Weight’ Method

The pressure at the top of a gas bubble at any point in the annulus while circulating it out using the “wait and weight” method can be calculated as follows:

By calculating the expected…