Learn how to convert pressure into equivalent mud weight into equivalent mud weight as per following formulas.

Oilfield Unit

Convert pressure in psi  unit into equivalent mud weight in ppg by using feet as the unit of measurement

Equivalent Mud Weight in ppg = pressure in psi ÷ 0.052 ÷ True Vertical Depth (TVD) in ft

Example:
Pressure = 5,000 psi
True vertical depth = 8,000 ft
Equivalent mud weight, ppg = 5,000 psi ÷ 0.052 ÷ 8,000 ft
Equivalent mud weight, ppg = 12.0 ppg

Metric Unit

Convert pressure in KPa unit into equivalent mud weight in Kg/m³ by using meters as the unit of measurement

Equivalent Mud Weight in Kg/m³ = Pressure in KPa × 1000  ÷ True Vertical Depth (TVD) in meters ÷  9.81

Example:

Pressure = 35,000 KPa
True Vertical Depth = 2,500 meters
Equivalent mud weight, kg/m³= 35,000 × 1,000 ÷ 2,500 ÷ 9.81
Equivalent mud weight, kg/m³= 1,427  kg/m³

Please find the Excel sheet for converting pressure into equivalent mud weight.

Ref book: 

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.