## 1. Calculate pressure gradient in psi/ft from mud weight in ppg

Pressure gradient in psi/ft = mud weight in ppg x 0.052

Example:
Mud weigt = 9.0 ppg
Pressure gradient in psi/ft = 9.0 x 0.052
Pressure gradient in psi/ft = 0.468 psi/ft

## 2. Calculate pressure gradient in psi/ft  from mud weight in lb/ft3

Pressure gradient in psi/ft = mud weight in lb/ft3 x 0.006944

Example:
Mud weight = 80 lb/ft3
Pressure gradient in psi/ft  = 80 lb/ft3 x 0.006944

OR

Pressure gradient in psi/ft t = mud weight in lb/ft3 ÷ 144

Example:
Mud weight = 80 lb/ft3
Pressure gradient in psi/ft  = 80 lb/ft3 ÷ 144

## 3. Calculate pressure gradient in psi/ft from specific gravity (SG)

Pressure gradient in psi/ft = mud weight in SG x 0.433

Example:
Fluid specific gravity = 2
Pressure gradient in psi/ft = 2.0 x 0.433

## 4. Convert pressure gradient in psi/ft to mud weight in ppg

Mud weight in ppg = pressure gradient in psi/ft ÷ 0.052

Example:
Mud weight in ppg = 0.5 psi/ft ÷ 0.052
Mud weight = 9.615 ppg

## 5. Convert pressure gradient in psi/ft to mud weight in lb/ft3

Mud weight in
lb/ft
3 = pressure gradient in psi/ft ÷ 0.006944

Example:
Mud weight in lb/ft3 = 0.5 psi/ft ÷ 0.006944
Mud weight = 72 lb/ft3

## 6. Convert pressure gradient in psi/ft to mud weight in SG

SG = pressure gradient, psi/ft ÷ 0.433

Example:
SG = 0.5 psi/ft ÷ 0.433
SG = 1.1547

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.

### Related Post

Understand Pressure Loss (Frictional Pressure) in ... Frictional pressure is pressure loss acting in the opposite direction of fluid flow and today we will look into each component in pressure therefore y...
Increase Mud Weight by Adding Calcium Carbonate Carbonate is weighing agent mostly used in horizontal well because it does not plug up formation. We can use the same weight up concept with barite to...
Drilling Formula Excel Sheet Version 1.2 Free Down... This is the second up date of drilling formula spread sheet, Drilling Formula Excel Sheet Version 1.2. Drillingformulas.com distributed the first v...
Determine the density of oil and water mixture You normally get the oil/water ratio from a retort so you can use these numbers to determine density oil and water mixture by the following formula. ...
Share the joy
•
•
•
•
•
•
•
•
•