Page 80 - Formulas and Calculations for Petroleum Engineering

Drilling engineering formulas and calculations Chapter 2 73

2.165 Percentage of bit nozzle pressure loss 144 2.203 Stripping/snubbing calculations—Maximum allowable
2.166 Plastic viscosity—Bingham plastic model 144 surface pressure governed by casing burst pressure 159
2.167 Plug length to set a balanced cement plug 145 2.204 Stripping/snubbing calculations—Maximum allowable
2.168 Polar moment of inertia 145 surface pressure governed by formation 160
2.169 Polished rod horsepower—Sucker-Nod pump 145 2.205 Stripping/snubbing calculations—Minimum surface
2.170 Pore-pressure gradient—Rehm and Mcclendon 146 pressure before stripping 160
2.171 Pore-pressure gradient—Zamora 146 2.206 Stripping/snubbing calculations—Constant bhp
2.172 Pressure analysis—Pressure by each barrel of mud with a gas bubble rising 161
in casing 147 2.207 Stroke per minute required for a given annular
2.173 Pressure analysis—Surface pressure during drill velocity 161
stem test 147 2.208 Stuck pipe calculations—Method-1 161
2.174 Pressure gradient 147 2.209 Stuck pipe calculations—Method-2 162
2.175 Pressure required to break circulation—Annulus 148 2.210 Subsea considerations—Adjusting choke line
2.176 Pressure required to break circulation—Drill string 148 pressure loss for higher mud weight 162
2.177 Pressure required to overcome gel strength of mud 2.211 Subsea considerations—Casing burst
inside the drill string 148 pressure-subsea stack 162
2.178 Pressure required to overcome mud’s gel strength 2.212 Subsea considerations—Choke line pressure loss 163
in annulus 149 2.213 Subsea considerations—Maximum allowable mud
2.179 Pump calculation—Pump pressure 149 weight—Subsea stack from leakoff test 163
2.180 Pump calculations—Power required 149 2.214 Subsea considerations—Casing pressure decrease
2.181 Pump displacement 150 when bringing well on choke 164
2.182 Pump flow rate 150 2.215 Subsea considerations—Velocity through choke line 164
2.183 Pump head rating 151 2.216 Surface test pressure required to frac the formation 164
2.184 Pump output—gpm 151 2.217 Total amount of solids generated during drilling 165
2.185 Pump output triplex pump 151 2.218 Total heat energy consumed by the engine 165
2.186 Pump pressure/pump stroke relationship 152 2.219 Total number of sacks of tail cement required 166
2.187 Radial force related to axial load—Cementing 152 2.220 Total water requirement per sack of cement 166
2.188 Range of load—Sucker-Rod pump 152 2.221 Triplex pump factor 166
2.189 Rate of fuel consumption by a pump 153 2.222 Upward force acting at the bottom of the casing
2.190 Rate of gas portion that enters the mud 153 shoe 167
2.191 Relationship between traveling block speed and 2.223 Vertical curvature for deviated wells 167
fast line speed 153 2.224 Viscous shear stress at the outer mudcake boundary 167
2.192 Rock removal rate 154 2.225 Volume of cuttings generated per foot of hole drilled 168
2.193 Rotating horsepower 154 2.226 Volume of dilution water or mud required to
2.194 Side force at bit in anisotropic formation 155 maintain circulating volume 168
2.195 Sinusoidal buckling 155 2.227 Volume of fluid displaced for duplex pumps 168
2.196 Slurry density for cementing calculations 155 2.228 Volume of fluid displaced for single-acting pump 169
2.197 Solids analysis—High-salt content muds 156 2.229 Volume of fluid displaced for triplex pump 169
2.198 Solids analysis low-salt content muds 157 2.230 Volume of liquid (oil plus water) required to
2.199 Spacer volume behind slurry required to balance prepare a desired volume of mud 170
the plug 157 2.231 Volume of slurry per sack of cement 170
2.200 Specific gravity of cuttings by using mud balance 158 2.232 Volumes and strokes—Annular volume 171
2.201 Stripping/snubbing calculations—Breakover point 2.233 Volumes and strokes—Drill string volume 171
between stripping and snubbing 158 2.234 Volumes and strokes—Total strokes 171
2.202 Stripping/snubbing calculations—Height gain and 2.235 Weight of additive per sack of cement 172
casing pressure from stripping into influx 159 2.236 Weighted cementing calculations 172

2.1 Accumulator capacity
Input(s)

BC: Bottle Volume per capacity (gallons)
P P : Pre-charge Pressure (psi)
P S : System Pressure (psi)
P f : Final Pressure (psi)