I am a roughneck who works on a drilling rig and I had a lecture at work where they were explaining the forces involved in a pulley system. It worked out so that I actually had this lecture twice, but both times I was told that for mechanical advantage we need to have a floating sheave; both lecturers (two different lecturers for both of the times I received this lecture) also went on to say that if the pipe is stuck in the ground, we lose all mechanical advantage. My instincts told me he was wrong, so I posted the question on the physics forum here (as well as much more detail regarding the problem).

To elaborate more, the problem that I can see is that drillers might severely underestimate the pulling force they are putting on the pipe which is stuck in the ground (since they will not account for mechanical advantage if they believed the lecturers words lecture). It's possible that this might cause an oversight and an accident could happen.

The lecturers were not engineers, but just other ex rig hands who took an office job.

So, how can I inform my company that the lecturers made a small oversight in what they said?

Also I don't want to be that guy. I don't want to be seen as cocky or too intelligent because in this industry it is often the case that people dislike thinkers. What can I do? What are my options? Should I just let it be thinking that the drillers (operators) probably knew that this was a mistake and just didn't want to say anything.


These days, you can make movies. One approach might be to talk in person to the lecturer and see if (s)he is interested in making a video that demonstrates the concept. In doing so, the error would become self-evident.

If someone else has already made a video, send the clip to the lecturers. Ask them why the video doesn't agree with their content.

  • Is there not some Engineer that you could raise it with informally on H&S grounds if nothing else
    – Neuro
    Jun 24 '13 at 22:47
  • @Neuro - This is the best course, if the option is available. Jun 25 '13 at 7:36

Do a demonstration. Showing a bunch of formulas isn't going to cut it. Have a 120 lb office secretary or bring one of your kids to work and use the pully to lift a 200lb barbell or some other object where everyone knows the weight and fits your math. This is the stuff you guys deal with, so I don't think it would come across as geeky.

Maybe this will upset the lecturers, but you have a little more responsibility for yours and the safety of the people you work with.

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