This article will teach you about the stripping procedure for non-migrating kick. This procedure is used to strip to desired depth but it won’t account for volumetric bleed therefore it is mainly applicable for stripping with non-migrating kicks as water or oil.
The stripping procedures are as follows;
Figure 1 – Stripping to the bottom with non-migrating kick
1. Calculations
- Determine whether the drillstring weight is over the pressure force pushing upwards.
- Determine how many feet that you need to strip to penetrate the kick
- Determine pressure increase when the drillstring penetrate the kick.
- Determine safety factor. If you plan to use the constant surface pressure method for the stripping operation, the safety factor added into the system must be sufficient to compensate the effect of influx penetration.
- Determine volume bleed back per stand if you plan to use the volume accounting method.
2. Stab a safety valve (full opening safety valve) and close the valve and then follow by an IBOP valve.
Figure 2 – Stab a safety valve and IBOP
3. Ensure no leakage between connections.
4. Adjust the closing pressure to allow the stripping operation.
5. Open Full Opening Safety Valve (FOSV) and strip the drillstring into the well until you get the desired safety factor. While stripping, small volume of fluid leakage around the pipe is a good sign because the closing pressure is not too much but the leak must stop when the stripping operation is stopped.
Figure 3 – Stripping with adjusted closing pressure
6. Strip to the required depth based on your selected method. You have a choice to use either the volume accounting or the constant surface pressure. You can read more details about these two methods from this article “Stripping Methods for Non Migration Kicks When There is an Off Bottom Well Control”.
References
Cormack, D. (2007). An introduction to well control calculations for drilling operations. 1st ed. Texas: Springer.
Crumpton, H. (2010). Well Control for Completions and Interventions. 1st ed. Texas: Gulf Publishing.
Grace, R. (2003). Blowout and well control handbook [recurso electrónico]. 1st ed. Paises Bajos: Gulf Professional Pub.
Grace, R. and Cudd, B. (1994). Advanced blowout & well control. 1st ed. Houston: Gulf Publishing Company.
Watson, D., Brittenham, T. and Moore, P. (2003). Advanced well control. 1st ed. Richardson, Tex.: Society of Petroleum Engineers.