NGWA Air Rotary Practice Exam

These questions are part of the practice quiz. Start practicing

• Which formation type is best described by using a soft tri-cone bit?
• Mud weight primarily serves to:
• Explain the rating of weight to viscosity in mud rotary drilling.
• How do power break-out tools operate on a drill string?
• When should permanent casing be set in mud rotary drilling of a rock well?
• Which factors are used to size air rotary rigs?
• Which of the following is an advantage of air rotary drilling over mud rotary?
• Which method is commonly used to reduce caving in soft formations?
• Which development technique involves forcing air to move cuttings?
• How can differential sticking be best controlled?
• How does RPM vary in relation to the diameter of the hole in air rotary drilling?
• How are drill subs used in the drill string?
• The size of the cuttings is used as an indicator of bit condition. Which statement best describes this?
• How are screen lengths determined?
• What is the purpose of specific capacity when sizing a well screen?
• Why is drilling fluid pressure important in mud rotary drilling?
• In air rotary drilling, high-pressure systems are typically used for which condition?
• Mud weight is normally adjusted by adding:
• What is a gauge ring? How does it indicate bit wear?
• Mist drilling is a name given to what technique in air rotary drilling?
• How does the cost per foot of air rotary compare with mud rotary in unconsolidated formations?
• Which drive system is generally simpler with lower cost?
• Which control method is explicitly listed for solids buildup in drilling mud?
• What is a surfactant? When is it needed?
• Which geological factor is important to consider for proper grouting of unconsolidated formations?
• Which factors affect mud viscosity?
• Which of the following statements describes a primary benefit of chip catchers during drilling?
• What is usually the cause of fishing in mud rotary drilling operations?
• What is the design rationale for rock-forming bit nozzles in mud rotary drilling?
• What best distinguishes a natural gravel pack from an artificial gravel pack?
• What are some advantages and/or disadvantages of the top head and table drive system?
• Which method to place gravel uniformly around the well screen?
• Why is it important to identify the boundaries of an aquifer?
• Which statement about table drive systems is true?
• Which combination correctly describes the materials and methods used in gravel-packed wells?
• Which of the following is NOT a daily air compressor check?
• What does daily maintenance on a mud rotary rig typically include?
• When troubleshooting cavitation, why should you check mud levels in the pit?
• How are PVC casing strings joined?
• Which of the following is NOT a listed method to set screens in air rotary drilling?
• After cutting several hundred feet of hard rock the rate has slowed down. What is the probably cause?
• What could cause excessive wear on the drill pipe?
• How is high solids in drilling muds measured and what methods are used to control solids buildup?
• Which of the following is a disadvantage of air rotary drilling related to pressure control?
• What can cause lost circulation in mud rotary drilling?
• Which description accurately reflects the use of heavy drill collars?
• What safety and efficiency benefit do power break-out tools provide during tripping operations?
• Heavy steel casing would best be used in what rotary process?
• Which statement best describes the relation of RPM between DHH bits and roller cone bits?
• Water pressure and air pressure can work against each other. Explain.
• How much pressure of air does it take to lift 100 ft of water?
• What are bentonite materials?
• Uphole velocity in soft formations can cause caving. How can you handle this problem?
• For fractured formations, which bit design is recommended?
• Which condition is a potential cause of lost circulation in air rotary drilling?
• After the bore hole has been cased to the rock formation, how can drilling rates be increased using air rotary?
• Which option is NOT a function of drill pipe in drilling unconsolidated formations?
• Injecting water into the air stream during drilling has what effect in rock formations?
• Explain the difference between high and low volume air rotaries.
• What is a disadvantage of the top head drive system?
• Which scenario is appropriate for gravel packing?
• Which bit design is typically used in soft unconsolidated formations?
• What are the typical RPM ranges for roller cone bits and DHH bits in hard rock drilling?
• Lost circulation problems in rock formations are usually caused by what conditions?
• Which statement about cuttings best describes drilling efficiency?
• Which option is NOT described as a method for controlling solids buildup in drilling mud?
• Explain percentage retention in designing a screen for a gravel well.
• Which methods are used to develop wells that are air rotary drilled?
• If the centrifugal mud pump starts cavitating after entering rock, what should you do?
• Which statement best describes why it is important to keep the bit in gauge during drilling?
• Which of the following is a daily air compressor check?
• What is a disadvantage of down hole hammer drilling?
• What is the function of the cable pull-down system on a mud rotary rig?
• What condition leads to differential sticking?
• When are grouting and/or cementing typically performed in air rotary drilling?
• What type of rock formations are in the sedimentary group?
• What is the purpose of a Kelly saver sub?
• What type of rock formations cause excessive bit wear?
• Crooked holes can cause other problems. How can you control drift in air rotary drilling?
• How does down pressure vary due to formation changes in air rotary drilling?
• How can you control caving problems with air rotary drilling?
• What methods are used to set screens in air rotary drilling?
• What factors can change rates of penetration in rock formations?
• What is the typical uphole annular velocity range for most air rotary drilling?
• Why do soft formations require low annular velocities?
• Percentage retention describes:
• Foams and additives are used to control which situations in air rotary drilling?
• Which elevator type uses slips that engage with the casing to provide a secure hold by applying weight on the slips?
• Which is an advantage of drill collars in unconsolidated formations?
• What down pressure is required on the drill string to operate the DHH drill in hard rock per inch of bit diameter?
• Before drilling into a known water producing rock formation, what should the mud characteristics be?
• Which formation condition is a limitation for air rotary drilling?
• When up-hole velocities decrease, which could be a probable cause?
• What is one primary purpose of heavy drill collars?
• Gravel packing is used in wells under which condition?
• Mud rings can be controlled by what methods?
• What viscosity mud should you have for continuing drilling after you have drilled into rock and set the casing?
• What information should you have available when determining well screen design?
• Which bit type is typically used for hard rock formations with mud rotary drilling?
• Explain misting. What is misting in drilling operations?
• When is the casing string grouted in mud rotary drilling of a rock well?
• Which conditions would typically call for an increase in air volume when hard rock drilling?
• Which of the following is a method used to speed up hole cleaning with air rotary?
• Which instrument is used to measure solids loading in drilling mud by assessing density and cuttings volume?
• Which method describes driving the casing down with a hammer or rig?
• In mud rotary drilling for unconsolidated formations, how do higher RPMs relate to feeds?
• Why must drilling fluids be compatible with PVC casing in mud rotary drilling?
• Which factors primarily influence the risk of borehole instability during drilling?
• Roller cone bits are best suited for which type of formations?
• What happens when the drill bit starts balling in air rotary drilling?
• Which of the following are indicators that fracture zones are encountered?
• What additives may be added to water to aid mud rotary drilling?
• Which statement describes rotating the casing into place using the drill rig?
• Which combination can help correct a crooked hole when using air rotary drilling?
• What is the purpose of stabilizers in air rotary drilling?
• Which signs indicate a permeable formation during drilling?
• After a water bearing formation is located, what is necessary to clean up the formation?
• What is a formation packer and where should it be used?
• When is gravel packing usually necessary in air rotary wells?
• Which type of elevator is designed specifically for casing and grips the casing with a latch mechanism?
• Polyphosphates are used for what purpose?
• Two holes drilled with mud rotary in the same rock formations have different penetration rates. What are the probable causes?
• Which of the following is listed as a precaution when sand seams are encountered during air rotary drilling in unconsolidated formations?
• Which of the following is NOT a method used to clean the hole of cuttings in air rotary drilling in unconsolidated formations?
• How does bit design vary with geology?
• In unconsolidated formations, which statement about borehole stability is true?
• What is an advantage of down hole hammer drilling?
• Explain the difference between high and low pressure air rotaries.
• Which materials are suitable for properly grouting a mud rotary well?
• Why are setting and developing screens typically not necessary in most rock formations?
• What property makes bentonite especially useful in drilling fluids?
• What is a common consequence of bridging in the finishing mud hole prior to development?
• How can storage coefficients be measured in unconsolidated formations?
• Which unit is used to express down pressure on the DHH drill string in hard rock?
• How is sand content in drilling mud measured?
• What fluids are used in air rotary drilling in unconsolidated formations?
• What equipment is commonly used to sharpen DHH drill bits?
• How do bit nozzles differ between rock formations and unconsolidated formations in mud rotary drilling?
• Which maintenance practice helps minimize wear on the drill pipe?
• Mud rings on the drill string due to mud seams are indicated by which combination of signs?
• How best can you determine a highly permeable rock formation?
• Differential sticking of drill pipe can be prevented by what methods?
• What are drill slips and how are they used?
• Gel-strength refers to which property in drilling fluid?
• Which elevator type uses a bail to suspend lighter casing or tubing?
• Which statement about the relationship between annular velocity and rock conditions is true?
• What can affect pH in unconsolidated formations?
• Are drag bits used in rock formations with mud rotary rigs?
• Can annular velocities of the drilling mud be slower or faster in rock formation as compared to unconsolidated formations?
• Which formations are best to use a soft tri-cone bit?
• Which option describes a method to control both caving and mud rings during air rotary drilling?
• What are the most common types of mud pumps?
• Which of the following is a disadvantage of air rotary drilling in loose formations?
• What type of lubrication system is used for DHH drilling?
• Artificial gravel packs involve adding specially selected gravel around the screen to enhance filtration and stability.
• What is the effect of maintaining a constant weight on the bit during drilling?
• Which of the following is NOT part of regular rotary swivel maintenance?
• Which statement best describes the cost per foot relationship between air and mud rotary in unconsolidated formations?
• Which of the following is a performance benefit of drill collars related to vibration?
• As the hole deepens in air rotary drilling, how must the air pressure change to maintain effective cuttings removal?
• Which statement best describes not typically part of daily mud rotary maintenance?
• If gravel packing is not used when needed, what problem is likely to occur?
• Which of the following is an advantage of high pressure air rotary drilling in unconsolidated formations?
• Drag bits are recommended for which formation type?
• Explain the term dusting in drilling. What happens during dusting?
• In hard rock drilling with roller cone bits, which statement correctly describes the speed and feed relationship?
• Heavy steel casing in air rotary drilling primarily serves to:
• What are the recommended pressure and air volume ranges for operating down hole hammer drills?
• What causes cavitation in pumping during drilling?
• The cable pull-down system uses what components to apply downward force on the drill string?
• Which measure helps reduce wear on the kelly bar?
• Which sampling method is described as continuous sampling of cuttings in air rotary drilling in unconsolidated formations?
• Which factor is considered when selecting mud additives for viscosity control?
• Which statement best describes the use of foam or polymers during drilling in unconsolidated formations?
• Which of the following is NOT listed as a factor affecting hole cleaning and penetration rates in air rotary drilling?
• Which of the following is a potential risk of high pressure air rotary drilling in unconsolidated formations?
• What are hydrating clays and how are they typically managed in mud rotary drilling?
• What causes differential sticking?
• Electric logging provides information on which of the following?
• What is a potential consequence of using higher RPM with too much feed in hard rock drilling?
• A bentonite-cement mix is commonly used for which purpose in mud rotary drilling?
• What could cause bridging when cleaning the finishing mud rotary rock hole prior to development?
• Which statement best describes artificial gravel packs?
• How are non-ferrous casing materials, such as PVC, handled in mud rotary drilling?
• Which of the following is NOT a common fishing tool used in rotary drilling?
• Mist drilling is used to achieve what effect in air rotary drilling?
• In gravel-packed screening around a well, what is the primary role of the surrounding gravel?
• Which additive is commonly used to improve viscosity in mud rotary drilling fluids?
• Which sampling options are used to obtain good samples in mud rotary drilling of unconsolidated formations?
• Which of the following is NOT a field maintenance task for drill bits?