Page 79 - Formulas and Calculations for Petroleum Engineering

72 Formulas and calculations for petroleum engineering

2.73 Effective weight during drilling 106 2.120 Kick analysis—Maximum pit gain from a gas
2.74 Effective wellbore radius for finite-conductivity kick in water-based mud 126
fractures 106 2.121 Kick analysis—Maximum surface pressure from
2.75 Effective wellbore radius in infinite-conductivity a gas kick in water-based mud 126
fractures 107 2.122 Kick analysis—Shut-in drill pipe pressure 127
2.76 Efficiency of block and tackle system 107 2.123 Kick analysis—Height of influx 127
2.77 Equivalent area of pipe subject to uniform axial force 108 2.124 Kill weight mud determination—Moore equation 127
2.78 Equivalent circulating density 108 2.125 Kinetic friction 128
2.79 Equivalent density of a wellbore fluid 109 2.126 Laser specific energy 128
2.80 Equivalent formation water resistivity from SP log 109 2.127 Lateral load imposed on a casing
2.81 Equivalent mud weight—Deviated well 109 centralizer—Cementing 129
2.82 Equivalent mud weight—Vertical well 110 2.128 Lateral load imposed on a casing centralizer
2.83 Evaluation of centrifuge 110 with a dogleg—Cementing 129
2.84 Evaluation of hydrocyclone 111 2.129 Linear annular capacity of pipe 129
2.85 Fluid volume required to spot a plug 111 2.130 Linear capacity of pipe 130
2.86 Force applied to stretch material 112 2.131 Load to break cement bond—Cementing 130
2.87 Force exerted by the fluid on the solid surface of 2.132 Mass rate of flow through annulus 131
flow through an annulus 112 2.133 Matching conditions at the cake-to-rock
2.88 Friction factor in drill pipe 113 interface—Formation invasion 131
2.89 Front displacement of a particle in the 2.134 Maximum allowable mud weight 131
reservoir—Formation invasion 113 2.135 Maximum drilling rate—Larger holes 132
2.90 Gas migration velocity 114 2.136 Maximum equivalent derrick load 132
2.91 Gas solubility in a mud system 114 2.137 Maximum length of a slanted well in a given
2.92 Gas/mud ratio 114 reservoir thickness 133
2.93 Gel strength—Optimal solid removal efficiency 115 2.138 Maximum length of drillpipe for a specific
2.94 Gel strength—Solid control efficiency 115 bottomhole assembly 133
2.95 Gel strength—Solids build-up in system 116 2.139 Maximum recommended low-gravity solids 133
2.96 Height of cement in the annulus 116 2.140 Maximum recommended solids fractions
2.97 Hydraulic horsepower 116 in drilling fluids 134
2.98 Hydraulics analysis 117 2.141 Maximum weight on bit 134
2.99 Hydromechanical specific energy 118 2.142 Mechanical energy balance for wellbore fluids 134
2.100 Hydrostatic pulling 118 2.143 Mechanical specific energy 135
2.101 Hydrostatic pulling wet pipe out of the hole 119 2.144 Mud rheology—Herschel and Buckley law 135
2.102 Hydrostatic pressure in annulus due to slug 119 2.145 Mud rheology—Power-law model—Consistency
2.103 Hydrostatic pressure decrease at total depth index 136
caused by gas-cut mud 119 2.146 Mud rheology—Power-law model—Power-law index 136
2.104 Impact force—Nozzle hydraulic analysis 120 2.147 Mud rheology—Power-law 136
2.105 Impringing jet 120 2.148 Mud rheology calculations—Bingham plastic model 137
2.106 Increase mud density by barite 121 2.149 Mud weight increase required to balance pressure 137
2.107 Increase mud density by calcium carbonate 121 2.150 Mud weight reduction by dilution—
2.108 Increase mud density by hematite 121 Water/diesel/any liquid 137
2.109 Increase volume by barite 122 2.151 Mudcake growth equation—Formation invasion 138
2.110 Increase volume by calcium carbonate 122 2.152 Mudcake growth equation-2—Formation invasion 138
2.111 Increase volume by hematite 122 2.153 Mudcake permeability—Formation invasion 139
2.112 Initial volume required to achieve a volume with 2.154 New pump circulating pressure 139
barite 123 2.155 Nozzle area calculation 139
2.113 Initial volume required to achieve a volume with 2.156 Number of sacks of cement required 140
calcium carbonate 123 2.157 Number of sacks of cement required for a given
2.114 Initial volume required to achieve a volume with length of plug 141
hematite 124 2.158 Number of sacks of lead cement required for annulus 141
2.115 Injection/casing pressure required to open valve 124 2.159 Number of sacks of tail cement required for casing 141
2.116 Input power of a pump—Using fuel 2.160 Open-ended displacement volume of pipe 142
consumption rate 124 2.161 Overall efficiency—Diesel engines to mud pump 142
2.117 Jet velocity—Nozzle hydraulic analysis 125 2.162 Overall power system efficiency 143
2.118 Kick analysis—Influx 125 2.163 Penetration rate—Drill-rate model—Alternative
2.119 Kick analysis—Formation pressure with well equation 143
shut-in on a kick 126 2.164 Penetration rate—Drill-rate model—Basic equation 143