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Avoid Drill Stem Failure

There can be a lot of drill stem and cutting tool damage depending on how you cut.
Lessons learned in the training class.

Avoid drill stem failures by cutting from the top down and don't take ledges that are too big.Where we can sometimes have 10 to 15 different refineries, I was discussing and pointing out the mechanisms that caused drill stem failure. I’m going through  my material and I’m pointing out that a lot of the drill stem failures are from cutting techniques. As we de-inventory the coke drum, it’s taking out hundreds of tons of coke.  If the coke cutter sluice air driller does not do it properly, it can pinch the drill stem and cutting tool. Cutting from the top down is the method we use and we don’t take ledges that are too big. Avoid bent drill stems in the delayed coker

A gentleman in the back says. “Gary you mind if I ask the rest of the class, does everybody in here cut from the top down or from the bottom up.  Unanimously the class said from the top down. So he sits back down.
Ruhrpumpen cutting toolI finish my material and later at break he came up to me and he says, “Gary for 40 years we’ve been cutting from the bottom up.  We have a lot of damage to our drill stem and our cutting tool. We have a lot of plug offs and we’ve always wondered why.”

So because he was alone without any outside information, he didn’t even know that you could cut from the top down.  That was a great lesson learned for him, for me and for the industry.

Learn Best Practices and Industry Standards from the PROS at

-Gary Pitman Coker Subject Matter Expert, Refining Community.

For more practical articles on delayed coker operations, see Gary’s Blog at

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Posted by: Gary Pitman