Height of influx will increase when the drillstring penetrates a kick; therefore, hydrostatic pressure decreases and casing pressure increases in order to compensate this situation.
If the casing is maintained constant while penetrating the kick, you will have high chance to take more influx because of underbalance situation (Figure 1). This article will teach you about how to determine pressure increment while penetrating into the kick, what to look for, etc. [click to continue…]
This is excellent oilfield footage about the overall process of offshore deepwater drilling and completion. It has about 5 minutes with good animation that will give you clearer picture of how the deepwater operation works from the beginning.
We also add VDO transcription for anybody who cannot catch all the content of the VDO. [click to continue…]
Shallow gas is one of the most dangerous incidents in well control because you don’t have the BOP set to be able to control the well. Additionally, shallow gas always happens at the shallow depth as surface hole section where you will have a difficulty to control the well. This footage below show you how serious of the shallow gas in an offshore environment.
Sedco 700 Shallow Gas Blow Out 6 June 2009
Additional details about shallow hazards that you need to know.
Pressure drop through surface equipment is one of the components in drilling hydraulics that must be considered. When we talk about surface equipment, we usually refer to those following equipment as a stand pipe, surface hoses, a swivel, a gooseneck and a Kelly.
Well control with pipe off the bottom is one of the most serious well control situations because kick below a drillstring can create very complicated situations when compared to a normal well control. This article will teach you about the basic well control when the pipe off bottom.
There are several well control techniques to manage when the kick comes into the well and it is below the pipe;
Use the Volumetric technique. The volumetric well control to let the gas migrate to surface with the bottom hole pressure nearly constant. This option is applicable when the influx is gas.
Strip the drillstring back to the bottom. This is applicable with non-migration kicks as water and oil.
Strip the drillstring utilizing the volumetric well control. This method can be used when you have a gas influx.
Snub (push) the pipe against the wellbore pressure down to the bottom
Kill the well off bottom using conventional well control methods as driller’s method and wait and weight. Typically, this is not recommended to use because you won’t get the kick out of the well and you may not be able to determine the kill weight mud correctly.
This is a very bad oilfield incident happened recently, Drilling Site in Washington County Caught on Fire. According to the NEWS, the failure of the rig equipment results in the fire situation. The hydraulic oil from ruptured high pressure hose spilled out and caught on fire. We would like to share this news to you in order to raise aware of of oilfield safety.
Equipment failure causes fire at Washington Co. gas drilling site.
Spokesperson said an equipment failure was the cause of a fire at a gas drilling site in Washington County Wednesday evening.
Dispatchers from 911 confirmed calls came in around 5:15 p.m. for a working fire at the Jeffries drilling location near Ross Road in North Strabane Township.
During a drill well on paper phase, wells might be planned based on available data from offset wells or nearby areas. This information may deviate from the actual drilling phase due to several reasons therefore it is very critical to have good monitoring and evaluating pore pressure while drilling. The actual pore pressure will dictate where to set the casing, how much the actual mud weight should be, what potential problems are, etc.
The actual reservoir pressure obtained while drilling will be used to determine right mud density in order to ensure an adequate primary well control. Besides the well control, the proper mud weight can help us in several aspects such as minimizing lost circulation and pipe sticking and maximizing a rate of penetration. You can achieve the trouble free drilling operation.
Have you ever wonder how the directional tool works, why we need GYRO tool, what magnetic interference is ,etc. It is very difficult to find the answer even though we have internet. Recently, my friend shares me this excellent book, Introduction to Wellbore Positioning by Prof Angus Jamieson at University of the Highlands & Islands. This is one of the best books regarding wellbore positioning. In the book, only does it have the text, but also contains tons of picture which will help learners to get more understanding of this topic.
What Will You Learn from the Introduction to Wellbore Positioning?
Formation pressure is important information for well planning and operation because it impacts on several things as well control, casing design, drilling fluid program, pore pressure prediction, etc. We will discuss about formation pressure in a basic term for drilling personnel.
During an era of sedimentation and erosion, little grains of sediment are constantly building above each other, usually in an environment of full irrigation. As the sediment thickness of the base layer increases, the sediment grains are packed strongly near to each other, and some water is excluded from the small pore spaces. Though, if the pore spaces through the deposit sediments are connected to the top pressure surface, the fluid at any depth in the sediment will be same as that which would be found in a simple column of fluid.