Please read and comment on the following fascinating article about SCVF problems written by my invited expert: Djilali Sahnoun – Technical & Engineering Manager. Many wells experience surface casing vent flow (SCVF) and subsequent gas migration to the surface through one of the following issues: a cemented casing string(s) with either a micro-annulus between casing and cement, a […]
Mud Displacement, the ‘mystery’ factor in gas and fluids migration
Very often I find myself helping people having issues with fluids migrating following primary cementing. In all these cases, it is always fascinating to see the frequency of this problem nowadays. Especially with the involvement of expert services companies and the availability of state-of-the-art engineering and products solutions. I have already written here about fluid […]
Mixing Energy or Shear Rate? The effect on Cement Slurry?
Back in 2016, I posted an article on laboratory testing for cement slurries. In this article, I briefly referred to the changes in the preparation of the slurry in the laboratory, to account for the additional mixing energy typical in small slurry volume jobs using a batch-mixer. (Like in coiled tubing/CT operations). A typical use […]
As a cementer, you are required to isolate a possible influx zone at 1600m, What can you do?
Influx zone characteristics These wells may show high dogleg severity in the intermediate section. Depending on the type of formation drilled across, there could be a tendency to form sort of keyseats, not only low side but also high side. They tend to get worse with additional drill string work, such as trips, reaming or circulation. […]
LCM Equipment: Using it Through Float Before Cementing
Using LCM through float equipment before cementing In some cases, we can see losses while running the casing or circulating before cementing. These losses open up the alternative to pump a Loss Circulation Material (LCM) pill as a possible mitigation method. This will then lower the losses ahead of the cement job itself. However, based on my experiences […]
Good or bad cement job? 7 Criteria
Well, this is the question: Was it a good or bad cement job? The final answer will depend on the objectives of the job. We ask ourselves, were they met? In most cases, additional information is required, like a cement evaluation log, a pressure test or even further data during the well’s completion. However, some immediate […]
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