What is sinosoidal and helical buckling? And why do I have to think about it?

An episode from the series "Fun with Drilling Engineering" with Prof. Dr. Matthias Reich.
Camera and cut : Susann Klein
Made at the Institute of Drilling Engineering and Fluid Mining of the Technische Universität Bergakademie Freiberg, Germany.
The education of Petroleum Engineers belongs to the program "Geo- Engineering", spezialization "Geo Energy Systems".
Please feel free to visit our homepage on tu-freiberg.de/fakult3/tbt​​​... or send feedback, enquiries or suggestions to [e-mail].
Voiceover Artist: Bamisebi Joseph Adetiloye

[@Gabobahr]

Hi, very interesting videos. I didn't recognize you last time we met in Anger's rig but I had seen your videos before.
I'm going to keep learning from you.
Best regards,
Gabriel

[@aldiansyahwahfi]

Hi. i really like the way you explain things. If I may request a topic, can you cover the mechanism of "bit walk"? you did mention it in one of your video, but I think I need a more in-depth coverage of the topic. Thank you in advance!