I would like to summarize about driller’s method with these simple steps as listed below;

1. Shut in the well and get pressure data (casing pressure and drill pipe pressure). The float bumping procedure may be conducted depending on whether you have a float in the drillstring or not.

2. Perform the well control calculations

3. Establish Circulation as per driller’s method

Fist circulation of Driller’s Method

a. Bring the pumps up by holding casing pressure constant

b. Circulate out the influx by holding drill pipe pressure constant

c. Shut down pumps by holding casing pressure constant

Second circulation of Driller’s Method

d. Raise mud weight up to desired kill mud weight

e. Bring the pumps up to speed by holding casing pressure constant

f. Circulate kill mud to the bit by holding casing pressure constant

g. Switch to hold drill pipe pressure

h. Circulate kill mud to surface by holding drillpipe pressure constant

i. Ensure that kill mud is all around by measurement, not by calculated stroke counts

j. Shut down pumps by holding casing pressure constant

k. Check casing pressure and drill pipe pressure. Both pressures must be 0 psi. You may see trapped pressure so as to make sure this is the trapped pressure, bleed pressure in small amount and observe pressure. Pressure should not increase after bleeding off. If pressure is building back after bleed off, there is still kick in the wellbore. You need to circulate more or raise the mud weight

Driller’s Method Rules

I also would like to emphasize these two vital rules of driller’s method that you need to keep in your mind all the time.

1st rule: Anytime you do something with pumps as start, stop or change pump speed, you must always hold casing pressure constant. This is very important.

2nd rule: For all other times, you always hold the side that has constant fluid density.

Reference book: Well Control Books

I just got questions from my friends asking about how casing pressure and drillpipe pressure react while performing the 2 nd circulation of driller’s method.

I have this post for somebody missing about the first circulation of driller’s method –  How are pressure and pit volume doing during the first circulation of the driller’s method?

During 2nd circulation of driller’s method, we need to hold casing pressure constant until kill weight mud to the bit and then we will hold drill pipe pressure constant. The reason why we do like this is that we need to maintain the constant bottom hole pressure.

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