What was happened? Kelly was bent.

We just got photo from our friend sharing these images of Kelly which was bent from parted drillstring.
This is the details.

While working the stuck drillstem using the kelly rig system, maximum tensile load applied on surface was about 375 Klb (170 tonne)  and the over pull was about 155 klb (70 tonne) and then the drill pipe was suddenly parted. This resulted in the Kelly to pop out of rotary table and the swivel bail came out of the hook. Therefore, the Kelly fail down freely because there was nothing to hold it. The equipment went down with the Kelly which was bent due to falling action from the rotary table to outside of the rig floor. Fortunately, nobody got injured from this incident.

Kelly-Bent-Over-From-The-Rotary-Table-1 Kelly-Bent-Over-From-The-Rotary-Table-2


We don’t have more details about where it was happened but we can learn from this incident.

What Can We Learn?

  • Always stay away from the rig floor and derrick while working with high tension. Drillers must be responsible to clear all personnel prior to work the stuck drill string.
  • Ensure when working with high tension, the weakest part of the string must be exactly known. Don’t not apply tensile over what it should be.
  • Not only is the rig floor dangerous place, but also catwalk is very extremely dangerous. Everything can fall from the rig floor to the catwalk. If you are there, you will be likely injured.

What Is Your Thought?

Please feel free to share with us in the comment box below.

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Working in the oil field and loving to share knowledge.

3 Responses to What was happened? Kelly was bent.

  1. Li Kejin says:

    Working with high tension should add overpull step by step and marked on kelly or pipe each time.

  2. Mohamed Ali says:

    Thank you for all the information. Every thing is possible in drilling ,I appreciate the driller who knew how to save the LIFE of the others.
    1)-It could be a human mistake(more over pull than expected)
    2)- A fault indicator indication
    3)-A wrong calculation for the present D/PIPE capacity (tensile and safety margin)
    4)- lack of concentration

  3. Aung Myint thein says:

    Most of drilling rig s,which use kelly have lock for hook and this type of happening impossible,but cause by driller may be not train one for that experience.
    Precaution are
    1.Driller must check weight during hand over to know weight
    indicator function or not.
    2.Driller must known the hole drill string weight from calculation or
    from drilling engineer.
    3.Driller must care for all indicators in his control panel.
    4. The only one of material fault is Casing line cut off
    but this also impossible due every drilling engineer already cut
    with Ton-mile calculation.

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