Equivalent Circulating Density (ECD) in ppg

Equivalent Circulating Density (ECD) is the effective density that combines current mud density and annular pressure drop. ECD is vital for drilling engineering since it limits how depth of each section to be drilled and leads to losses.


The equivalent circulating density formula is shown below

Equivalent Circulating Density (ECD) in ppg = (annular pressure loss in psi) ÷ 0.052 ÷ true vertical depth (TVD) in ft + (current mud weight in ppg)


Annular pressure loss = 400 psi
True Vertical Depth = 8,000 ft
Current mud weight in ppg = 10 ppg

ECD in ppg = (400 psi ÷ 0.052 ÷ 8,000 ft) + 10.0 ppg

ECD = 11.0 ppg

Please find the Excel sheet to calculate equivalent circulating density (ECD)

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 Engineer

Related Post

Formation Pressure from Kick Analysis Once you shut in the well in and obtain shut in drill pipe pressure, you can estimate formation pressure by applying the hydrostatic pressure concept....
Example of Real Gas Calculation This example will demonstrate how to calculate the compressibility of real gas in order to determine gas density and specific gravity at a specific co...
Increase oil/water ratio The concept of increase oil water ratio is to increase oil volume in the system without any changes in water to meet new oil water ratio. How can ...
Calculate Specific Gravity (SG) in oilfield unit You may need to calculate specific gravity from different density or pressure gradient units. This post demonstrates you about specific gravity calcul...
Share the joy
  • 167
Tagged , , . Bookmark the permalink.

About DrillingFormulas.Com

Working in the oil field and loving to share knowledge.

14 Responses to Equivalent Circulating Density (ECD) in ppg

  1. Andrew oloko says:

    I love well control and answers.

  2. Mahsun Hammedi says:

    Why you only use annular pressure drop?
    what about pressure loss inside the pipes?

    • Mahsun,

      The reason why using annular pressure drop is the direction of pressure drop acting downward which cause additional pressure to the bottom hole. The drill pipe pressure loss is acting upward therefore it cannot be used for ECD calculation.


  3. Francis Okoto says:

    How can we use this during cement to calculate the ECD especially during cement displacement.

  4. Egede Frank Chukwueku says:

    plenty thanks to you all. its great to be part of this group

  5. Arslan says:

    Can we calculate the ECD if the surface pressure is not equal to zero? Or the surface pressure does not matter?

  6. Mide says:

    Whoa I love this platform. Please I would like to know the relationship between ECD and EMW

Leave a Reply

Your email address will not be published. Required fields are marked *

This site uses Akismet to reduce spam. Learn how your comment data is processed.