Hydrostatic pressure is pressure created by fluid column and two factors affecting hydrostatic pressure are mud weight and True Vertical Depth.
You can read full details about hydrostatic pressure from this article, Understand Hydrostatic Pressure.
In this article, it will demonstrate how to calculate hydrostatic pressure in different oilfield and metric unit.
1. Calculate hydrostatic pressure in psi by using mud weight in pound per gallon (ppg) and feet as the units of True Vertical Depth.
Hydrostatic pressure equation:
Hydrostatic Pressure (HP) = 0.052 × Mud Weight × True Vertical Depth (TVD)
Where;
Mud Weight in ppg
True Vertical Depth in ft
Example;
Mud Weight = 12.0 ppg
True Vertical Depth (TVD) = 10,000 ft
Hydrostatic Pressure (HP) = 0.052 × 12.0 × 10,000
Hydrostatic Pressure (HP) = 6,240 psi
2. Calculate hydrostatic pressure in psi by using pressure gradient in psi/ft and feet as the units of True Vertical Depth.
Hydrostatic pressure equation:
Hydrostatic Pressure (HP) = Pressure gradient in psi/ft × True Vertical Depth (TVD)
Where;
Pressure gradient in psi/ft
True Vertical Depth in ft
Example;
Pressure Gradient = 0.5 psi/ft
True Vertical Depth (TVD) = 10,000 ft
Hydrostatic Pressure (HP) = 0.5 psi/ft × 10,000 ft
Hydrostatic Pressure (HP) = 5,000 psi
3. Calculate hydrostatic pressure in psi by using mud weight in lb/ft3 and feet as the units of True Vertical Depth.
Hydrostatic pressure equation:
Hydrostatic Pressure (HP) = 0.006944 × Mud Weight × True Vertical Depth (TVD)
Where;
Mud Weight in lb/ft3
True Vertical Depth in ft
Example;
Mud Weight = 80 lb/ft3
True Vertical Depth (TVD) = 10,000 ft
Hydrostatic Pressure (HP) = 0.006944 × 80 lb/ft3 × 10,000 ft
Hydrostatic Pressure (HP) = 5,555 psi
4. Calculate hydrostatic pressure in psi by using mud weight in PPG and meters as unit of True Vertical Depth.
Hydrostatic pressure equation:
Hydrostatic Pressure (HP) = Mud Weight × 0.052 × TVD in meters x 3.281
Where;
Mud Weight in ppg
True Vertical Depth in meter
Example:
Mud Weight = 12.0 ppg
True Vertical Depth (TVD) = 5000 meters
Hydrostatic Pressure (HP) = 12.0 × 0.052 × 5000 × 3.281
Hydrostatic Pressure (HP) = 10,237 psi
5. Calculate hydrostatic pressure in Pascal by using mud weight in kg per cu-meter (kg/m3) and meter (m) as the units of True Vertical Depth.
Hydrostatic Pressure (HP) = 9.81 × Mud Weight × True Vertical Depth (TVD)
Where;
Mud Weight in kg/m3
True Vertical Depth in meter
Example;
Mud Weight = 1,000 kg/m3
True Vertical Depth (TVD) = 100 m
Hydrostatic Pressure (HP) = 9.81 × 1,000 × 100
Hydrostatic Pressure (HP) = 981,000 pascal
6. Calculate hydrostatic pressure in bar by using mud weight in kg per cu-meter (kg/m3) and meter (m) as the units of True Vertical Depth.
Hydrostatic Pressure (HP) = 9.81 × Mud Weight × True Vertical Depth (TVD) ÷ 100,000
Where;
Mud Weight in kg/m3
True Vertical Depth in meter
Example;
Mud Weight = 1,000 kg/m3
True Vertical Depth (TVD) = 100 m
Hydrostatic Pressure (HP) = 9.81 × 1,000 × 100 ÷ 100,000
Hydrostatic Pressure (HP) = 9.81 bar
7ุ. Calculate hydrostatic pressure in atm by using mud weight in kg per cu-meter (kg/m3) and meter (m) as the units of True Vertical Depth.
Hydrostatic Pressure (HP) = 9.81 × Mud Weight × True Vertical Depth (TVD) × 9.8692 × 10-6
Where;
Mud Weight in kg/m3
True Vertical Depth in meter
Example;
Mud Weight = 1,000 kg/m3
True Vertical Depth (TVD) = 100 m
Hydrostatic Pressure (HP) = 9.81 × 1,000 × 100 × 9.8692 × 10-6
Hydrostatic Pressure (HP) = 9.6817 atm
Download Free Excel Spread Sheet
Download the Excel sheet for calculating hydrostatic pressure – This is 2020 update with Metric Unit
Ref books:
Lapeyrouse, N.J., 2002. Formulas and calculations for drilling, production and workover, Boston: Gulf Professional publishing.
Bourgoyne, A.J.T., Chenevert , M.E. & Millheim, K.K., 1986. SPE Textbook Series, Volume 2: Applied Drilling Engineering, Society of Petroleum Engineers.
Mitchell, R.F., Miska, S. & Aadny, B.S., 2011. Fundamentals of drilling engineering, Richardson, TX: Society of Petroleum Engineers.
how to calculat hydrostatic pressure in kg/ltter
thanks
You can use the conversion program here => https://www.drillingformulas.com/a-recommended-unit-conversion-program/
i want know how i can calculate the pressure at casing shoe,1000 psi at surface test and tvd of csg shoe 7500 ft and 11.0 ppg for fluid test?
P at shoe = Surface pressure + Hydrostatic pressure
P at shoe = 1000 psi + (0.052 x 7500 x 11) = 5290 psi.
I love this site
Leslie, what did you mean by surface pressure? The pumping pressure?
Like casing pressure which is in static condition.
I like this site very much,
Very simple and great explaination.
Very helpful
hello , I need to how to calculate the hydrostatic pressure with softwares .is there any software which is able to calculate that?
You can download our well control or drilling formula spread sheet. There is a formula inside.
I like this site too much (very simple and great info explaination
I like this site, very helpful
a little help to solve the problem …A well has been shot in at 10500 TVD, due to flow out increase. MW is 11.5 ppg and SIDPP reaches 600 psi.
What will be the the final STAND PIPE PRESSURE with the kill mud if the initial circulation BEFORE the kick was 2300 psi ?
Hi Alan,
This is the answer.
ICP = SCR + SIDPP
2300 = SCR +600
SCR = 1700 psi
KMW = OMW + SIDPP/(0.052 x TVD)
KMW = 11.5 + 600 / (0.052 x 10,500)
KWM = 12.6 ppg
FCP = ICP x (KMW/OMW)
FCP = 1,700 x(12.6/11.5)
FCP = 1,863 psi
Final circulating pressure = 1,863 psi.
how to know hydrostatic pressure difference after cement column set
Could you please give me more information so I can help you?
This site is very helpful. Thanks
Dear sir
This is a v good information for new comers in this field.
If you again start Quiez program it’s much better
very thankful to this site….!
Pingback: Cual es el Origen de la Constante 0,052 – Perfoblogger
Dear Sir,
how to calculate the hydrostatic of brine in annulus, before perform annulus pressure test
You still use the same formula. The density will be brine density in the annulus side.
What is 0.052
Hi Motaram,
Please find more information here – https://www.drillingformulas.com/how-does-the-0-052-constant-come-from/
How can i prove this HP=0.052*tvd*mud density
Hi Neutron,
This is the prove for 0.052 https://www.drillingformulas.com/how-does-the-0-052-constant-come-from/