trying to answer:
1) Not backreaming. Driller was doing 10-15 rpm to while rotating out. Torque were eratic, but increasing and got 30 t overpull and torque increased towards make-up torque (poor job pulling out).
2)YES! pure TORSIONAL failures will occur in connection. But NOT combined...
Guys
API pure torsion fomula Q = [0.096167 J Ym]/D, where J is polar moment of inertia, J=pi/32(D4-d4), Y minimum yield of material and D is outside diameter. d is inside diamenter of tube.
If a wash out in drill pipe occurs the size of the wash out, i.e. wash out area, can be estimated with...
deltaV = Cp*deltaP*V ------> YES, love it!
This is the formula, as i mentioned earlier as well. Casing is pre filled with oil based mud, casing is WAY thin (compared to ID) and cemented to formation wall and delta V is a fuction of cement pumping unit that is used for pressure testing...
Thanks guys!!!
I think for my purpose (pressure testing of casing, a 2000 m 9 5/8 ID steel tube cemented against formation) the simple formula: V (assuming fixed), mud compressibility at an assumed constant temp and given pump rate of pumping unit is sufficient....(?).
so that is: deltaV =...
Gentlemen and laydies
Does API say anything on reduction in torque (and axial yield) capacity when a wash out has occured in the drill pipe??
If not.....any personal ideas about strength reduction teqniques?
hope you can help, and look forward to replies
thanks
Gentlemen and laydies
Looking for a formula to predict simple pressure increase within a cylinder as a function of fluid pumped into the cylinder (pump rate).
suspect pressure to be dependent on size of fixed volume, fluid compressibility (oil in this case), and amount of fluid pumped.....(?)...
Hi all
Looking for formulas for acceleration of compressed steel tubes (and for force needed to compress tubes a certain amount) when submerged in water. Dont think the water does anything else besides provide buoyancy (?).
Feel free to comment formulas you might submit....
hope you can help...
