Let’s have one more test in order to remind you about the first circulation of driller’s method.
When you shut the well in, you record these following pressure readings.
Initial Circulating Pressure (ICP) = 1500 psi
Original Shut in Drill Pipe Pressure = 500 psi
After you circulate the 1 st step of driller’s method, you see drill pipe pressure and casing pressure reading like this image below.
What do you think about this well?
Before starting 1st circulation of driller’s method, you have this following information
Original Shut in Drill Pipe Pressure = 500 psi
Shut in casing pressure = 800 psi
After complete the 1st circulation, you shut down pumps and you see the drill pipe pressure and the casing pressure as this figure below
What do you think about this well?
You may confuse between Formation Integrity Test (FIT) and Leak Off Test (LOT).
They are different in this following aspect.
Leak Off Test – you pressure test shoe and formation until formation break down.
Let’s I explain more about it: Leak off Test is conducted in order to find the fracture pressure (fracture gradient) of formation and shoe. When conducting the LOT, you will pump drilling fluid to until you see the fracture trend of formation. Once formation is fractured, the first pressure that deviated from a trend is typically called Leak Off Pressure. We use the leak off pressure to calculate LOT.
Let’s take another quiz regarding driller’s method.
Before start the first circulating, you have the following information
Original Shut in Drill Pipe Pressure = 500 psi
Initial Circulating Pressure (ICP) = 1500 psi
After end of 1st circulation of Driller’s Method, the drillpipe pressure gauge and the casing pressure gauge shows that the circulating drill pipe pressure = 1500 psi and casing pressure = 500 psi (see the figure below).
What do you think about this well?
Trip Tank is a small metal tank with small capacity about 20-40 bbls with 1 bbl divisions inside and it is used to monitor the well. There are several operations that we can use the trip tank to monitor the well as follows;
1. Trip Out Of Hole (TOOH): While tripping out of hole, the trip tank is used to track volume of mud replacing volume of drill string. The volume of mud should be equal to displacement volume of any kind of tubular tripped out of hole.
2. Trip In Hole (TIH): While tripping in hole, the drilling string (bit, BHA and drill pipe) is ran back in the hole, the trip tank must be use to keep track volume gain. The expected volume gain should be equal to the displacement volume of whole string.
Learn more about pipe displacement
3. Flow check: The trip tank is utilized to determine well condition in order to see if the well is still under static condition.
