7000psi mud pressures at 4.5km..., page-28

Sekret...

I don't people are suggesting you are stupid, but your calculations and in deed assumptions are not quite right.

We did not start the thread on pascals law...yes it does apply...but that is not what we are talking about here.

the Cylinder is not a sealed unit...mud goes down the hole (pumped under pressure) and is forced up the cavity back to the surface, where it flows (open hole) into a shaker mesh to crch the drill chips before retuning to the mud pits for conditionaing before re-use.

The issue here is a simple one...what pressure does the mud (fluid) exert on the well bore walls at 4.5km depths?

Of course the methods I used were a basic assumption, which ignored all sorts of influencing factors such as adding surface pressures (14+psi)...bottom hole natural atmospheric increased, heat differentials (100c+ at these depths), viscosity, effects from additives, fluid velocities, friction coefficients, hydroscopic tension, etc, etc

Generally speaking however, the numbers I have presented are more or less close to the mark in relation to the sorts of pressures we might expect the column of drilling mud to be exerting on the "skin" build-up on the face of the well bore.

This was, after all, the nature of the thread.

Cheers!