7000psi mud pressures at 4.5km..., page-19

sekret,
" string mud pump pressure will be the same for its intire length".

not so

rgh term (r = greek ro) g = grav constant , h = height, is the determninant of pressure in stationary mud (can add velocity component if you wish and apply Bernoulis equation) . H will determine pressure at various heights

Fundamental stuff . High school physics.