Term
|
Definition
1.) Produce pore fluids
2.) Gain subsurface information
3.) Allow injection of fluids
4.) Exploit geothermal resources
5.) Disposing waste
6.) Drilling training/research wells |
|
|
Term
| Objectives of drilling operations |
|
Definition
1.) Minimize the total well cost
2.) Drill a useable hole
3.) Drill in a safe and environmentally sound manner |
|
|
Term
|
Definition
1.) Power system
2.) Hoisting system
3.) Fluid circulating system
4.) Rotary system
5.) Well control system
6.) Well monitoring system |
|
|
Term
| Hoisting system components |
|
Definition
1.) Derrick & substructure
2.) Block & tackle
3.) Drawworks |
|
|
Term
| Fluid circulating system components |
|
Definition
1.) Pumps
2.) Pits/tanks
3.) Mixing devices
4.) Contaminants removal equipment
5.) Flow conduits |
|
|
Term
|
Definition
1.) Swivel
2.) Kelly
3.) Kelly bushing
4.) Rotary drive
5.) Rotary table
6.) Drill string |
|
|
Term
| Well control system components |
|
Definition
1.) Mud flow indicator
2.) Pit volume indicator
3.) Hole fill indicator
4.) Trip tanks
5.) Pump strokes |
|
|
Term
| Well control system functions |
|
Definition
1.) Detecting a kick
2.) Close well at surface
3.) Circulating well under pressure and increase fluid density
4.) Move pipe under pressure
5.) Divert flow from rig |
|
|
Term
| Well monitoring system measures |
|
Definition
1.) Hook load
2.) Rotary speed
3.) Torque
4.) Pump pressure
5.) Flow rate
6.) Fluid density
7.) Mud temperature
8.) Pit level |
|
|
Term
| Direct functions of drilling fluid |
|
Definition
1.) Transport cuttings to surface
2.) Control formation pressure
3.) Exert sufficient hydrostatic pressure
4.) Prevent walls from caving
5.) Cool & lubricate drill string
6.) Reduce friction between hole & drill string
7.) Transmit hydraulic energy to drill motor, tools & bit |
|
|
Term
| Indirect functions of drilling fluid |
|
Definition
1.) Observe & detect information about the well
2.) Prevent drill string corrosion
3.) Limit formation damage
4.) Minimize hole problems such as loss circulation, stuck pipe, and wellbore instability |
|
|
Term
| Classification of drilling fluids |
|
Definition
1.) (L) Synthetic fluid
2.) (L) Water based mud
3.) (L) Oil based mud
4.) (M) Foam (mostly gas)
5.) (M) Aerated water (mostly water)
6.) (G) Air
7.) (G) Natural gas
8.) (G) Nitrogen |
|
|
Term
| Factors governing the selection of drilling fluids |
|
Definition
1.) Formation type
2.) Temperature
3.) Pressure
4.) Environmental concerns
5.) Water quality and availability
6.) Cost |
|
|
Term
| Physical properties of drilling fluids |
|
Definition
1.) Mud density
2.) Rheologic properties
3.) Filtrate loss and cake thickness
4.) Contents |
|
|
Term
| Routine drilling fluids tests |
|
Definition
1.) Mud weight or fluid density
2.) Marsh funnel viscosity
3.) Rheologic properties
4.)Filtration loss properties |
|
|
Term
|
Definition
1.) Control rheological properties of drilling fluids
2.) Enhance cuttings transport capacity of the mud
3.) Reduce fluid loss
4.) Decrease formation damage
5.) Reduce wellbore instability |
|
|
Term
|
Definition
| Increase volume of available fluids |
|
|
Term
|
Definition
|
|
Term
|
Definition
| Reduce viscosity by adding water or chemicals |
|
|
Term
|
Definition
|
|
Term
|
Definition
| Add weighting material or remove solids |
|
|
Term
|
Definition
| Remove undesirable solids and add desirable solids |
|
|
Term
|
Definition
| Chemicals are added to enhance certain mud properties |
|
|
Term
|
Definition
1.) Good/stable rheoligic properties up to 500*F
2.) Used for shale, salt, & water sensitive formations
3.) Effective under corrosion
4.) Superior lubricating characteristics
5.) Permits mud density as low as 7.5 lbm/gal
6.) Good for filtration control |
|
|
Term
| Oil based mud disadvantages |
|
Definition
1.) Higher initial cost
2.) Requires more stringent pollution control
3.) Reduced effectiveness of logging tools
4.) Harder to detect gas kick
5.) High cutting disposal cost |
|
|
Term
|
Definition
1.) Drilling into an over pressure formation
2.) Not keeping the hole full of mud
3.) Swabbing
4.) Mud gradient reduced due to contamination or poor maintenance
5.) Unplanned disconnect of a marine riser |
|
|
Term
|
Definition
1.) Increase in mud flow rate out of the hole
2.) Increase in surface mud volume
3.) Rise in mud pit level
4.) Gas cut mud |
|
|
Term
|
Definition
1.) Depends to a large extent on the composition of the kick fluids
2.) A gas kick causes a higher annular pressure than a liquid kick
3.) A gas kick has a lower density than a liquid kick, & it must be allowed to expand as it is circulated out of the well |
|
|
Term
|
Definition
1.) Net force due to hydrostatic pressure acting on submerged objects
2.) Generates forces and moments acting on the subsurface well equipment & drill string
3.) Reduces tension in drill string
4.) Causes high compression in drill collars |
|
|
Term
|
Definition
1.) Collars are in compression, while upper portion is in tension
2.) Neutral point is where there is no tendency to buckle
3.) Neutral point has 0 axial stress
4.) A long drill collar is often placed in the lower part of a drill string to keep neutral point below the drill pipe. |
|
|
Term
|
Definition
| BOP that closes around the drill pipe and restricts flow through the annulus |
|
|
Term
|
Definition
| Designed to cut/shear the drillstring and close the well. Last option. |
|
|
Term
| Main function of a swivel |
|
Definition
Transmit fluid while rotating.
Part of the rotary system |
|
|
Term
| Tools eliminated to achieve the top drive |
|
Definition
1.) Kelly
2.) Kelly bushing
3.) Swivel |
|
|
Term
| How tubular pipe is specified |
|
Definition
1.) Range
2.) Outer diameter
3.) Weight per foot
4.) Steel grade |
|
|
Term
| Main function of drill collars |
|
Definition
|
|
Term
|
Definition
1.) Loss of life
2.) Loss of equipment
3.) Loss of reserves
4.) Environmental destruction |
|
|
Term
| Device used to measure rheological properties |
|
Definition
|
|
Term
| Device that measures the density of a drilling fluid |
|
Definition
|
|
Term
| Device that measures the consistency of a drilling fluid |
|
Definition
|
|
Term
| Information derived from a geolograph |
|
Definition
1.) Depth
2.) Rate of penetration |
|
|
Term
| When is a liquid column non-linear |
|
Definition
|
|
Term
| Range of pH for a good drilling fluid |
|
Definition
9.5-11
1.) It would prevent corrosion
2.) Most drilling fluid would work in this range |
|
|
Term
| Two major mandatory safety equipment on drilling floor |
|
Definition
1.) Safety boots
2.) Hard hats |
|
|
Term
|
Definition
|
|
Term
| 6 Steps in the formation of sedimentary rocks |
|
Definition
1.) Erosion
2.) Transport
3.) Deposition
4.) Compaction
5.) Cementation
6.) Diagenesis |
|
|
Term
| Control center on the rig |
|
Definition
|
|
Term
| Operation of moving drill string under pressure |
|
Definition
|
|
Term
| Most of the rig power is consumed by |
|
Definition
1.) Hoisting system
2.) Circulating system |
|
|
Term
| 3 Different types of sedimentary rocks |
|
Definition
1.) Clastic
2.) Chemical
3.) Biological |
|
|
Term
| Most abundant sedimentary rock penetrated while drilling |
|
Definition
|
|
Term
| Hydrocarbons are generally found in what sedimentary rocks |
|
Definition
1.) Sandstone
2.) Carbonate |
|
|
Term
| 3 types of drilling fluids |
|
Definition
1.) Water based
2.) Oil based
3.) Air or gas based |
|
|
Term
|
Definition
It is a modern piece of equipment that helps rotation of the rig; powered swivel.
The top drive is a safer system |
|
|
Term
|
Definition
| Designed to close when no pipe is in the hole |
|
|
Term
|
Definition
| Long square or hexagonal steel bar with a hole through the middle for a fluid path. It is used to transmit rotary motion from the rotary table, or kelly bushing, to the drill string |
|
|
Term
|
Definition
| An adapter that connects the rotary table to the kelly |
|
|
Term
|
Definition
| Revolving or spinning section of the drill floor that provides power to turn the drill string |
|
|
Term
|
Definition
| Power swivel. Regular swivel, kelly, and kelly bushing are eliminated entirely. Uses a hydraulic motor to achieve rotation. Safer and easier for the crew members. |
|
|
Term
|
Definition
| Used to connect different sized tools and pipes |
|
|
Term
|
Definition
| Allows driller to impart a strong, hammer like blow to free the stuck BHA |
|
|
Term
|
Definition
| Cone shaped housing that imparts a whirling fluid motion like a tornado due to high velocity tangential fluid inlet |
|
|
Term
|
Definition
| Greatly dampens the pressure surge developed by the positive displacement pump |
|
|
Term
|
Definition
| A rotating cone shaped drum which has a screw conveyor attached to its interior. The rotation creates a force that throws the heavier particle to the outer housing |
|
|
Term
| Contaminant removal equipment |
|
Definition
1.) Shale shaker
2.) Settling pit
3.) Hydrocyclone
4.) Mud cleaner
5.) Degasser |
|
|
Term
|
Definition
1.) Annular Preventer
2.) Blind ram
3.) Shear ram
4.) Pipe ram |
|
|
Term
|
Definition
| is increase in bottomhole pressure due to a downward pipe or casing movement |
|
|
Term
|
Definition
| is a reduction in bottomhole pressure due to an upward pipe/casing movement; |
|
|
Term
| Consequences of excessive swab and surge pressures |
|
Definition
Well kick;
Formation fracturing;
Lost circulation; and
Sever formation damage. |
|
|
Term
|
Definition
| mill tooth and tungsten carbide insert. |
|
|
Term
|
Definition
| shearing or scraping the rock at the bottom of the hole. |
|
|
Term
|
Definition
|
|
Term
|
Definition
|
|
Term
| Basic Mechanisms for Rock Removal |
|
Definition
Wedging
Scraping and grinding
Erosion by fluid jet action
Percussion or crushing
Torsion or twisting |
|
|
Term
| Rotary Bit Rules of Thumb |
|
Definition
1. Roller bit are a good initial choice for the shallow portion of the well
2. Diamond drag bits perform best in non-brittle formation having a plastic mode of failure
3. PDC bits perform best in uniform sections of carbonate or evaporites
4. PDC bits should not be used in gummy formation |
|
|
Term
| How bit tooth wear graded |
|
Definition
| Bits are graded in terms of the fractional tooth height has been worn away and reported to the nearest eight. |
|
|
Term
| The rate of tooth wear depends primarily on: |
|
Definition
1. Formation abrasiveness
2. Tooth geometry (e.q. fractional tooth height, h)
3. Bit weight
4. Rotary speed
5. The cleaning and cooling action of the drilling fluid |
|
|
Term
|
Definition
1. Nonsealed roller
2. Sealed roller, and
3. Sealed journal. |
|
|
Term
| The Effect of Bit Weight on Bearing Life |
|
Definition
1. The number and type of bearings used
2. Whether or not the bearings are sealed. |
|
|
Term
| Factors Affecting Penetration Rate |
|
Definition
1. Bit type
2. Formation characteristics,
3. Drilling fluid properties,
4. Bit operating conditions (bit weight and rotary speed),
5. Bit tooth wear, and
6. Bit hydraulics. |
|
|
Term
| The formation pressure depends only on the |
|
Definition
|
|
Term
| Mechanisms That Cause Abnormal Pressure |
|
Definition
1. Compactioneffects
2. Diageneticeffects
3. Differential density effects
4. Fluid migration effects. |
|
|
Term
| Two Basic Approaches Used to Estimate Formation Pressure |
|
Definition
1. The Matrix Stress Method
2. Correlation Method |
|
|
Term
| Interval transit time depends on what parameter |
|
Definition
|
|
Term
| The Reasons for the Usual Increase in Penetration Rate in Abnormal Zone |
|
Definition
Decrease in the overbalance
Decrease in the rock strength caused by
undercompaction
The effect of overbalance is much more significant than the effect of undercompaction |
|
|
Term
| Drilling Parameters that Affect ROP |
|
Definition
Bit characteristics: Bit type, diameter, nozzle sizes, and wear,
Weight on bit
Rotary speed
Mud properties: type, density, viscosity
 Solids content and size distribution in mud,
Pump pressure and rate. |
|
|
Term
| Parameters Affecting Conductivity |
|
Definition
Lithology,
Water salinity,
Temperature
Drilling fluid invasion or interactions with the formation. |
|
|
Term
| For fracture fluid to enter the cavity |
|
Definition
| the pressure of the fracture fluid must exceed the pressure of the formation fluid in the pore spaces of the rock. |
|
|
Term
| Fracture occurs when the fluid pressure |
|
Definition
| exceeds the sum of the minimum matrix stress and the pore pressure |
|
|
Term
| Compression is greatest in the direction of the |
|
Definition
|
|
Term
| Primary Objectives of Well Cement |
|
Definition
1. Protect and support the casing,
2. Prevent the movement of fluid through the annular space,
3. Stop the movement of fluid into fractured formations, &
4. Close an abandoned portion of the well. |
|
|
Term
| Basic Cementing Procedure Includes |
|
Definition
1. Preparing cement slurry by mixing powdered cement, water and additives at the surface
2. Pumping the slurry by hydraulic displacement to the desired location
3. Letting the slurry to hardened, or reacted, to become a rigid solid that exhibits favorable strength and seal characteristics. |
|
|
Term
| The cement composition and placement technique for each job must be chosen so that the cement will |
|
Definition
| achieve adequate strength and sealing property soon after being placed in the desired location. |
|
|
Term
| The drilling engineer is concerned with the selection of the best cement |
|
Definition
| composition and placement technique for each required application. |
|
|
Term
| The main ingredient in almost all drilling cements, and why |
|
Definition
| portland cement, because it can be pumped easily and hardens readily in an underwater environment |
|
|
Term
| Components of Portland Cement |
|
Definition
1. Tricalcium silicate "C3S"
2. Dicalcium silicate "C2S"
3. Tricalcium aluminate "C3A"
4. Tetracalcium aluminoferrite "C4AF" |
|
|
Term
| The Main Cementing Compound |
|
Definition
| The main cementing compound in the reaction products is calcium silicate hydrate which is called tobermorite gel. |
|
|
Term
| Strength Contributors in Portland Cement |
|
Definition
1. C3S is considered to be the major contributor to strength.
2. C2S provides the long term strength.
3. C3A produces most of the heat of hydration.
4. C4AF has only minor effects on the physical properties of the cement. |
|
|
Term
| Cement specifications almost always are stated in terms of these standard tests. |
|
Definition
1. Fluid loss
2. Rheology
3. Permeability
4. Strength
5. Thickening time |
|
|
Term
| Test Equipment Needed To measure slurry properties: |
|
Definition
1. Mud balance
2. Filter press
3. Rotational viscometer
4. Consistometer for determining the thickening rate |
|
|
Term
| Test Equipment Needed To measure set cement properties: |
|
Definition
1. Cement permeameter for determining the permeability of the cement
2. Strength testing machines for determining compressive strength |
|
|
Term
|
Definition
| The apparatus consists essentially of a rotating cylindrical slurry container equipped with a stationary paddle assembly |
|
|
Term
| The thickening time of the slurry is defined as the time required to reach a consistency of |
|
Definition
|
|
Term
|
Definition
| is the amount of mixing water per sack of cement that will result in a consistency of 30 Bc at the end of this period. |
|
|
Term
|
Definition
| is the amount of mixing water per sack of cement that will result in a consistency of 11 Bc at the end of the test. |
|
|
Term
|
Definition
| is determined by pouring a 250-mL sample from the consistometer into a glass graduated cylinder and noting the amount of free water that separates from the slurry over a 2-hour period. |
|
|
Term
|
Definition
| is defined as the amount of water per sack of cement that will result in 3.5 mL of free water per 250 ml sample. |
|
|
Term
| The soundness of the cement is the |
|
Definition
| percent linear expansion or contraction observed after curing in an autoclave under saturated steam at a pressure of 295 psig for 3 hours. |
|
|
Term
| The fineness is expressed in terms of a calculated |
|
Definition
| total particle surface area per gram of cement. |
|
|
Term
| The fineness is determined from the rate of |
|
Definition
| The fineness is determined from the rate of settlement of cement particles suspended in kerosene in a Wagner turbidimeter. |
|
|
Term
| The three types of cement are: |
|
Definition
Ordinary "0“
Moderate Sulfate-Resistant "MSR"
High Sulfate-Resistant "HSR“. |
|
|
Term
| The water content of the slurry sometimes is expressed as |
|
Definition
| The water content of the slurry sometimes is expressed as water cement ratio in gallons per sack and sometimes expressed as a weight percent |
|
|
Term
|
Definition
Are used to provide acceptable slurry characteristics
Most of the additives are powders which can be easily blended with
cement
At present, the cement Classes G and H can be modified easily through the use of additives to meet almost any job specifications economically.
The use of a modified Class H cement has become extremely popular. |
|
|
Term
|
Definition
Density control additives (barite & bentonite),
Setting time control additives,
Lost circulation additives,
Filtration control additives,
Viscosity control additives, and
Special additives for unusual problems. |
|
|
Term
Slurry density is controlled using different methods:
|
|
Definition
Increasing water/cement ratio
Adding low-density solids (bentonite & diatomaceous earth)
Creating foamed cement (gas, surfactants and stabilizers)
Adding weighting agents such as barite. |
|
|
Term
|
Definition
Calcium chloride,
Sodiumchloride,
Hemihydrate
Sodium silicate. |
|
|
Term
|
Definition
Calcium lignosulfonate
Calcium-sodium lignosulfonate
Carboxymethyl hydroxyethyl cellulose (CMHEC) |
|
|
Term
Types of Cementing Applications
|
|
Definition
a. Cementing casing strings,
b. Cementing liner strings,
c. Setting cement plugs: Cement plugs are placed in open hole or in casing before abandoning the lower portion of the well, and
d. Squeeze cementing: Cement is squeezed into lost-circulation zones, abandoned casing perforations, or a leaking cemented zone to stop undesired fluid movement. |
|
|
Term
|
Definition
A rubber plug used to separate the cement slurry from other fluids,
Two types of cementing plug (bottom and top plugs)
The bottom plug is launched ahead of the cement slurry
A diaphragm in the bottom plug body ruptures
The top plug has a solid body |
|
|
Term
|
Definition
| expanding metal cone that is used to prevent the downward flow of cement in the annular space |
|
|
Term
|
Definition
| devices that attach to the casing to remove loose filter cake from the wellbore. |
|
|
Term
|
Definition
Keep the casing close to the center of the hole.
Help to uniformly distribute the cement sheath around the casing.
Improve the effectiveness of the cement seal between the wellbore and the casing. |
|
|
Term
|
Definition
A tapered or bullet-nosed piece of equipment often found on the bottom of a casing string.
Guides the casing toward the center of the hole
Minimizes problems associated with hitting rock ledges or washouts in the wellbore as the casing
is lowered into the well. |
|
|
Term
Casing Cementing Procedure
|
|
Definition
1. Slurry Preparation:
2. Releasing the Wiper Plug:
3. Pumping cement slurry into the casing:
4. Releasing the Top Wiper Plug:
5. Pumping Drilling/Completion Fluid |
|
|
Term
| The 2 general types of bearings used in rock bits |
|
Definition
1. Ball and journal
2. Ball and roller |
|
|
Term
| 3 factors that affect rock bit performance and that must be considered when selecting a rock bit |
|
Definition
1. Weight on bit
2. RPM
3. Formation |
|
|
Term
| Uses a 2 letter code for standardized dull bit grading system |
|
Definition
|
|
Term
| When a dull bit comes out of the hole we look for 2 things |
|
Definition
|
|
Term
| Formation characteristics involve |
|
Definition
1. drillability
2. abrasiveness |
|
|
Term
| 2 indicators used to determine when to terminate a bit run are |
|
Definition
1. torque
2. rate of penetration |
|
|
Term
| What kind of teeth are used in soft formations |
|
Definition
|
|
Term
| What type of teeth are used in hard formations |
|
Definition
|
|
Term
| What is an inhibitive drilling fluid |
|
Definition
| it is a drilling fluid who's ability to hydrate clays has been greatly reduced |
|
|
Term
| The major compound in most cement |
|
Definition
|
|
Term
| What compressive strength is needed to support casing pipe |
|
Definition
|
|
Term
| What is the starting point for better cement slurry design |
|
Definition
|
|
Term
| The volume of slurry that can be mixed per sack of dry cement is called |
|
Definition
|
|
Term
| Two materials used to increase cement slurry density |
|
Definition
|
|
Term
| What is usually used in wellswith bottom hole temperatures above 200 degrees F |
|
Definition
|
|
Term
| What is the principal strength producing material in cement |
|
Definition
|
|
Term
| High temperature and pressure will result in what kind of cement settling |
|
Definition
|
|
Term
| Which plug is run in the hole first? top or bottom |
|
Definition
| Bottom is first, followed by the top |
|
|
Term
| How do accelerators alter pumping time |
|
Definition
| they decrease pumping time |
|
|
Term
| 5 major cementing accessories |
|
Definition
1. plugs
2. float shoe
3. float collar
4. cementing head
5. scratchers |
|
|
Term
| 5 common additives added to cement |
|
Definition
1. calcium chloride
2. sodium chloride
3. bentonite
4. barite
5. potassium chloride |
|
|
Term
| When does a well kick occur |
|
Definition
1. When the wellbore pressure is less than the formation pressure
2. It is unintentional flow of formation fluid to the wellbore
3. Gas kicks are more dangerous than liquid kicks |
|
|
Term
| What does the annular pressure do during well control operations |
|
Definition
1. One of the most important applications of hydrostatic pressure analysis is the determination of annular pressure during well control operation
2. The proper well control strategy is to adjust a surface choke so that the bottom hole pressure of the well is maintained slightly above the formation pressure.
3. When circulating record pressure in the annulus and the volume of mud pumped- this is annular pressure profile |
|
|
Term
| Kick volume is normally determined from |
|
Definition
|
|
Term
| What does the bottom clearance angle of drag bits do |
|
Definition
1. It reduces the torque
2. It prevents the wedge from dragging the hole bottom while taking a chip
3. It should not be too high as it causes the bit to jump and chatter and to wear fast. |
|
|
Term
| What are the characteristics of drag bits |
|
Definition
1. They drill by physically plowing cuttings from the bottom of the borehole
2. They include bits with steel cutters, diamond bits, and PDC bits
3. They can be made from one solid piece of steel |
|
|
Term
| What are the cutting mechanisms of roller bits |
|
Definition
1. Wedging
2. Scraping & grinding
3. Erosion by fluid
4. Crushing
5. Torsion or twisting |
|
|
Term
| What types of formations are diamond drill bits usually used in |
|
Definition
| hard, non brittle formations |
|
|
Term
| What are polycrystalline diamond bits |
|
Definition
| They are bits that have man made diamonds mounted on the steel bit by being bonded with tungsten carbide. They do not have any roller parts and work primarily by wedging |
|
|
Term
| What are the PDC cutter orientation angles |
|
Definition
The cutter orientation must be properly matched to the hardness of the formation.
Aggressive cutter orientation angles for soft formations |
|
|
Term
| What does the bottom clearance angle do |
|
Definition
1. Reduces the required torque
2. Prevents digging too deep and stalling the bit whenever the weight-to-torque ration is high
3. Prevents the wedge from dragging the hole bottom while taking a chip
4. It should not be too high as it causes the bit to jump and chatter and to wear fast |
|
|
Term
|
Definition
1. It helps promote efficient wedging mechanism
2. The bit loses strength as the rake angle increases |
|
|
Term
| What type of bit would be used for drilling hard formations in the deep section of a well |
|
Definition
|
|
Term
| What are the characteristics of diamond bits |
|
Definition
1. They set in a tungsten carbide matrix
2. Under proper bit operation only the diamond contact the hole bottom
3. Size and number of diamonds used depends on the hardness of the formation to be drilled
4. For hard formations the bit should have many small stones |
|
|
Term
| What kind of holes do long taper bits drill |
|
Definition
| Straight holes with higher bit weight |
|
|
Term
| What kind of holes do short tapered bits drill |
|
Definition
| They are used for directional drilling applications |
|
|
Term
| What is the cuttings transport ratio for a good hole cleaning |
|
Definition
|
|
Term
| When the particle slip velocity is zero, what is the cutting transport ratio |
|
Definition
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Term
| As the particle slip velocity increases, what happens to the transport ratio |
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Definition
| the transport ratio decreases |
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Term
| As the slip velocity decreases, what happens to the concentration of cuttings in the annulus |
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Definition
| the concentration of the cuttings in the annulus decreases |
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Term
| Why do drill bits have nozzles |
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Definition
1. To aid in transport of cuttings
2. To prevent regrinding of cuttings |
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Term
| Under what circumstances do solid particles not settle in a Bingham fluid |
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Definition
1. High viscosity (apparent)
2. High yield strength |
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