What is Primary Well Control?

Primary Well Control is hydrostatic pressure provided by drilling fluid more than formation pressure but less than fracture gradient while drilling. If hydrostatic pressure is less than reservoir pressure, reservoir fluid may influx into wellbore. This situation is called “Loss Primary Well Control”.

Not only is hydrostatic pressure more than formation pressure, but also hydrostatic pressure must not exceed fracture gradient. If mud in hole is too heavy, it will cause a broken wellbore, you will face with loss circulation problem (may be partially lost or total lost circulation). When fluid is losing into formation, mud level in well bore will be decreased that will result in reducing hydrostatic pressure. For the worst case scenario, you will lose the primary well control and wellbore influx or kick will enter into wellbore.

Typically, slightly overbalance of hydrostatic pressure over reservoir pressure is normally desired. You must keep in mind about the basic of maintaining primary well control that you must maintain hole with drilling fluid that will be heavy enough to overbalance formation pressure but not fracture formations.

Reference book: Well Control Books

Related Post

Annular Preventers – Well Control Equipment Annular preventers are the most versatile well control equipment and there are many names referring it as bag preventers, or spherical preventers. The...
Maximum surface pressure from kick tolerance facto... You have learned about the kick tolerance factor from the previous blog posting and this article will demonstrate you how to use the kick tolerance fa...
Bullheading Calculation Example Bullheading is one of the well control methods that involve pumping formation fluids back into formation into a shut-in well. You can read the basic d...
Good website about petroleum engineering schools Today, I have one site that I would like to recommend for you guys who would like to study in oil and gas as petroleum engineers. There are may areas ...
Share the joy
  •  
  •  
  •  
  •  
  •  
  •  
  •  
  •  
  •  

About DrillingFormulas.Com

Working in the oil field and loving to share knowledge.
Tagged . Bookmark the permalink.

4 Responses to What is Primary Well Control?

  1. Pingback: What is Secondary Well Control?‎

  2. Ehis Oribhabor says:

    Like to know if there is a training or course available wireline operations from your end.
    Thanks
    Ehis

  3. Gokul sharma says:

    Well control is most important of drilling session whatever we use the instrument which is used for drilling but starting of any problem our first focus must be primary well controll

Leave a Reply

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