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162 Cards in this Set
- Front
- Back
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What is the idea behind a cloverleaf?
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eliminates all cross traffic movement, no one ever has to take a left hand turn
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How density of roads is determined?
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The area of the road divided by the given area of land
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What are the two major patterns for road design?
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grid/perpidicular pattern and contour pattern with the land
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What is the most common shape of city blocks? Why is it used?
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rectangular blocks allows houses to fit together best in a small area
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What is the major problem of plotting a north-south grid on the surface of a spherical earth?
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the curves in the earth's spherical shape make north-south complicated, north is not directly straight up and vice versa
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What is the dominant pattern of roads in the Midwest?
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rectilinear because of flat land
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How has the Land Ordinance Act (LOA) helped in creating roads?
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of the land given, everyone had to give 33 ft part of land to roads
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What was the width of roads created by LOA? What is the significance of that width?
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66ft was the length of a measuring/surveying device called Gunter's Chain
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What are the origins of many of present roads?
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many animals walking on them and patted them down and compacted. Animals have an acute sense of knowing the shortest distance between two places
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Why did people choose high roads to travel?
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the lower roads are more wet in the valleys and mud was hard to get through
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What was the major purpose of the Land Ordinance Act of 1785?
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divided land into grids for townships
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What is the road pattern architects favor in planning new developments? Why?
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contour is easier to build on earth and cheaper, easier to drive on, easy construction
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What is the major problem with the grid pattern in San Francisco?
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very steep hills makes sidewalks have to be stairways
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Long straight sections of roads are usually avoided. Explain why.
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so drivers do not speed up too much and they do not get too drowsy behind the wheel
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Why one mile of every 5 highway miles must be straight and free of obstructions?
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so that airplanes can emergency land on them
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What is the difference between parkways and freeways?
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parkways have sharper curves, steeper grades and shorter sight distances. This typically accounts for lower legal speed limits. Freeway separated by median and held to higher standard
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What are the purposes of using curves and grades? What are the factors limiting their use?
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accounts for mountains or valleys which cars must either travel around, over or under, or through. Want to minimize the cost and time of construction. Factors are type of traffic, design speed determines the radius of the curve, the weather of a given area.
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Name the major purposes of engineering codes?
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To have standards for roads and to ensure public safety
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There exist two distinctive geometrical styles for highway building. Describe these styles.
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one way is by laying out long straight segments and then connecting them with relatively short curves. The alternative is to start with sweeping curves and then join them with short straight sections.
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What is the difference between design speed and legal speed limit?
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The design speed is the actually maximum speed a car can drive on a road without flying off the road, and the legal speed is a designated speed a car can drive on a given road enforced by laws.
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List four of the factors that affect road design.
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How sharp the curves will be, the width of the lanes, what will it do when it reaches a mountain top, the design speed, and the length of each straight away, the weather, terrain that road will be built on, type of material that you will use on the road
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Route 40 has many nicknames. State three thereof.
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Ocean-to-Ocean highway, and the old Lancaster Turnpike, the scenic route, the historic route
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Who were the builders of El Camino Real? What cities did it join? What is it today?
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The Spanish built the El Camino Real, joining Mexico City to Sonoma, which is north of San Francisco. Today it is U.S Highway 101.
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What are the major advantages and disadvantages of road patterns made of soft curves, loops, and cul de
sac? |
The advantages are that they account for the houses and topography of a given area. However, many of the roads lead back to where they began, making it sometimes difficult to find your way around.
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What are the general rules for route numbering in the US?
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The basic idea is that east-west routes get even numbers, and north-south roads odd numbers. The major, long distance routes are assigned numbers less than 100, ending in either 0 or 5. East has larger numbers than west, north has larger numbers than south
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What is the purpose of a diamond type interchange?
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It connects a major highway with a lesser road.
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How does a traffic circle work?
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A traffic circle is used to manage traffic at intersections. This allows cars entering from several directions to choose several destinations. This avoids the use signal lights and stop signs.
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What is the major difference between a cloverleaf interchange and a directional interchange?
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In a directional interchange, the third dimension becomes a factor. This requires two more levels of roadway, making a four-leveled structure all together.
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What does it take to make a left turn and a U turn on a cloverleaf?
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To make a left turn, you must turn 270 degrees to the right. To make a U turn, one must do a full 540 degrees.
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What is the major drawback of a cloverleaf?
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The loop roads have to turn rather sharply, causing cars to have to slow down.
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What is the difference between flagstone and cobblestone in road building?
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Flagstones are set flat (or horizontal), while cobblestones laid on end (or vertical).
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What is a macadam pavement?
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Macadam pavement is a texture created by John Loudon McAdam, which is a well-compacted layer of fine, broken stone that is strong and durable when laid directly on the natural roadbed.
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Define the term “traffic calming”. How is it achieved?
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Traffic calming is the concept of making traffic flow faster and smoother. This is done by the opposite of what most think might be done; making streets narrower and more crooked, and to build obstructions that compel drivers to calm down.
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Name some of the accessories used in traffic calming.
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Speed bumps, speed humps, and speed tables.
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Name some of the opponents of traffic calming. Why do they oppose it?
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Fire-and-rescue services often oppose traffic calming because they need space to be able to drive quickly and efficiently to emergency. Another opponent is residents in neighborhoods.
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Why was (and still is) asphalt a preferred binder in road construction?
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Freshly laid hot asphalt is a gooey semi-liquid that remains somewhat flexible after it cools.
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What are the drawbacks of asphalt pavement?
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Any defects or irregularities in the underlying foundation will telegraph through to the surface. As well as this, it softens in hot weather. Where cars brake, it waves up and ruts
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Name two benefits of rigid concrete pavement as compared with flexible one?
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Concrete is stiffer and stronger.
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What are the drawbacks of rigid concrete pavement?
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Although concrete is stronger and stiffer, it cracks open, leaving a hole with jagged edges where a void in the foundation has formed, has to be built in blocks.
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What is the difference between expansion and contraction joints in concrete pavement? what is the solution to it
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An expansion joint has a built in gap so two blocks of concrete can move either toward or away from each other. A contraction joint is closed solid when the roadway is first poured. Solution is tie-bar that is fixed in one slab and moves freely in the other
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What could be a probable solution to eliminate expansion and contraction joints in concrete pavement?
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Building roads with a stronger material that reinforces gaps where the joints would be laid.
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Compared with the days of pre motor vehicle, what is it that makes pavement work today?
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The pneumatic tire.
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Name some road accessories that minimize loss of life in cases of accidents.
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Guardrails (made of various materials and shapes), crash cushions, signposts, and runaway truck lanes.
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How can road signs and lane marks be seen at night?
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They rely on retro reflective coatings. These bounce the light back in whatever direction it came from.
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Traffic jams are analogous to a flooding river. In what way do they differ?
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When a river swells with the spring flood, it doesn’t slow down; the velocity increases along with volume of water. As well as this, cars (which can be compared to molecules of water) do not bounce in to one another to speed up a traffic jam.
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What is the function of metered entrance ramps on freeways? How do they work?
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This dribbles cars onto the highway at a controllable rate. This avoids buildups from cars entering a highway.
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What are Botts dots? Describe their function.
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The plastic reflectors embedded in the centerline and edges of many roadways. They become more visible in heavy rain, and provide not only visual guidance but also a tactile and auditory warning if you were to stray out of your lane.
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What are the major differences between conventional traffic lights and Light Emitting Diodes (LEDs)?
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Instead of one big bulb filtered by colored glass, the LED signal has a geometric array of small, semiconductor devices that emit various distinct colors of light.
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How to optimize traffic light times?
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By installing motion sensors, magnetic, and radio waves into the roads and traffic lights so they time themselves based on the flow of cars.
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What is a big no-no in traffic signals? How can it be avoided?
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Allowing two conflicting streams of traffic to both get a green light at the same time. The main line of defense against such a disaster is a conflict-monitoring unit built into every computerized controller cabinet. This can tell with certainty if two greens are incorrectly lit at the same time.
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How can traffic lights be made responsive to emergency vehicles?
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A special type of detector is installed that allows fire engines and ambulances to preempt normal traffic signals. Frequency is read by detector.
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Approximately, how many highway and railroad bridges in the USA?
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About 600,000 highway bridges, and about 100,000 railroad bridges.
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What are the principal components of a girder bridge?
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A girder bridges consists of two vertical blocks (piers) with a horizontal block laid across the two (stringers).
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What is a truss?
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A truss is a structure that is designed to maximize strength and stiffness while minimizing the quantity of material.
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Why are fasteners used in bridge building?
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Fasteners prevent any tipping of the bridge caused by a horizontal force or a force from the side
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What is the function that girder bridges serve? How is it achieved?
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The function is support heavy loads to be able to cross from point a to point b. This is done by making sure that all the beams and girders are supported at both ends. This means that all the forces from the weight of the bridge can be transmitted directly downward.
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What was the main purpose of constructing covered bridges?
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Covered bridges kept the wooden framework of the bridge out of the weather, therefore protecting it from rot.
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In addition to the top and bottom chords in truss bridges, name other members used in truss
bridge construction. Name the forces that these members could be subjected to. |
The diagonals which are used in truss bridge construction are also subjected to compression as well as tension.
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What was the material first used in truss construction? Why its use became limited?
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The first material used in truss construction was wood, however this has become limited as iron and steel became economically attractive.
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Give examples of steel sections used in resisting compression and others used in resisting
tension forces. |
The top chords which are subjected to compression, must be beams of substantial cross section, and the bottom chords which are subjected to tension need to be thin rods or even flexible chains or cables where strength is the key factor, not stiffness.
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What are the forces acting on the top chords and bottom chords in a truss bridge?
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The top chords are under compression, and the bottom chords are in tension.
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What is the major difference between a rectangular and a triangular truss?
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A triangular truss has the property of natural rigidity; it cannot be bent without breaking something.
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What is the main idea behind the Pratt Bridge design where the middle of the span is thickest and
diminishes near the support? |
The bending stress on the bridge is greatest in the middle and diminishes toward the ends; thus it makes sense to give the truss its maximum depth and strength only in the center.
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The Whipple bowstring truss has two major components. What are they?
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The bowstring is half arch and half truss. The upper chord is a curved arch held in compression and prevented from spreading out by tension in the lower chord, which also forms the deck of the bridge.
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What is the main idea behind a cantilever bridge design?
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A cantilever bridge makes the center of the span the lightest part of the structure rather than the heaviest allowing the bridge to be built even longer yet still support heavy weight.
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Considering a truss bridge and a cantilever bridge, name the basic geometrical difference in the
profiles of both bridges. |
A cantilever structure is a structural member supported only at one end. This means it has to be anchored or balanced so it will not topple over.
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How is the weight acting on a cantilever bridge counterbalanced?
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This weight is counterbalanced by adding counterweights on the opposite side of each beam.
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What is the major construction advantage of cantilever bridges?
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Cantilever bridges are self-supporting structures even while they are being built.
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What is the major advantage of stone arch bridges?
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This structure operates entirely under compression; this is an advantage if you are building with materials such as stone or brick, which don’t have much strength under tension.
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What are the two major disadvantages of stone arch bridges?
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First, the arch is a stable structure only when it is complete. Second, there is an outward thrust at the base of the arch, which has to be resisted somehow or the arch will spread out and collapse
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What is the main advantage of a suspension bridge? How does it transmit its loads?
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functional transparency. Tall towers are built on opposite sides of the channel to be crossed. Stout cables are draped across the tops of the towers, the smaller wire ropes, called cable stays, are hung vertically from the main suspension cables. Finally, the bridge deck is attached to these cable stays.
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What is the name of the mathematical shape of the main cables of a suspension bridge? What is
the origin of this name? What does this shape resemble? |
The mathematical shape of the main cables of a suspension bridge is called catenary, which comes catena, the Latin word for chain. This shape resembles a parabola.
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What are the factors suspected in the failure of the Tacoma Narrows Bridge?
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“resonance” where a small force produces large effects by periodically reinforcing natural vibrational motions of the structure. Along with this, there was an aerodynamic “flutter” which twisting of the bridge in fact generated more twisting. This was due to the loose tightening of the vertical cables from which the deck was hung.
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What is the major difference between a suspension bridge and a cable-stayed bridge?
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A cable stayed bridge essentially eliminates the suspension cables. Instead of hanging cable stays vertically from the giant draped cables, the strays are fanned out directly from the tower to the deck.
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What are the technical difficulties associated with increasing the span of a cable-stayed bridge?
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As the angle of the stay increased beyond 45 degrees, the stays exert more horizontal force than vertical force and thus tend to buckle the roadway rather than hold it up.
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Is the Brooklyn Bridge considered to be of the suspension type, cable-stayed, or both? Why?
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It is both. Although the weight of the deck is carried mainly by four catenary cables, diagonal stays fan out from the towers to add stability.
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How can a cable-stayed bridge be made asymmetrical?
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Asymmetry can be achieved by making the spans to the left (or right) of a tower longer than those on the opposite side.
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What are some of the advantages and disadvantages of floating bridges?
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Instead of driving upwards on a bridge, a floating bridge allows to drive to decline in slope. Despite this, they are vulnerable to currents, tides, floods, and ice.
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What is the main convenience afforded by moveable bridges? What is the major drawback?
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A moveable bridge closes to let cars or trains through, and opens to let ships pass. The major drawback is that all mechanisms which make a moveable bridge need to be in sync with one another. If one fails, then the entire bridge fails.
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Name three types of moveable bridges and state the characteristics of each.
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a) The bascule bridge has a section of the bridge which pivots upwards.
b) The lift bridge is essentially an elevator for a section of road or railroad. c) The swing bridge pivots horizontally like a compass needle. |
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Why are moveable bridges presently out of favor?
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The main reason for this is the cost of operation, both for maintaining a finicky mechanism and for keeping a worker on duty to open the bridge.
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Name some of the accessories found in a bridge’s underbelly.
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The contraptions that allow the pieces of the bridge to move without falling apart are called bridge bearings. There are steel plates that slide over each other, steel plates separated by lubricating pads of various kinds, “nests” of small steel rollers, single large rollers, hinged bars that suspend the bridge deck like a porch swing, rack-and-pinion structures, and elastic rubber pads.
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True or false, and why: a bridge capable of resisting earthquakes is one that can move freely over
its foundation. |
True. These bridges are equipped with restraints meant to hold joints together, allowing it to move freely but not so far that it falls off when the earth begins to shake
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Tunnels require continuous services. Name some of these services.
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Tunnels need to be ventilated, drained, lighted, and safe from flood and fire calls.
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Describe the cut-and-cover technique used in building tunnels.
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The cut and cover technique is as follows: dig a trench, put the road or rail line it, and add a roof.
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Name other methods used in digging tunnels.
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Other methods include assembling a tube on the surface and sunk into a trench, and digging a tunnel from both ends by either blasting in hard rock or by a rotary boring machine that chews through the ground.
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How is the cut-and cover technique applied in water?
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A tube is assembled on the surface and sunk into a trench dredged into the river bottom, then it is covered for protection from ship and anchors and the like.
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What is shortening of a mountain tunnel? How can it be achieved? What purpose does it serve?
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Shortening of a mountain tunnel means to go higher up a mountain, which makes the approach roads longer or steeper or both. This allows engineers to not have to cut through as much solid earth.
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Are mountain tunnels or river ones more prone to leakage problems? Why?
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Mountain tunnels are because the rock is fissured and porous.
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Holland tunnel has a unique fire resistance system. Describe it.
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The Holland tunnel has been fitted with a ceiling deliberately designed to collapse, therefore to prevent any fire that may sprout within the tunnel.
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Why is fire a major concern in tunnels in general and in those electrically operated rail tunnels
(such as the Channel Tunnel) in particular? How is this problem treated? |
Because the nearest help to such fires could be more than 10 miles away. To treat this problems drivers that are subjected to fire are instructed to stop as soon as smoke is detected. Static electricity can build up when fast moving cars and sparks can ignite it. water cooling systems cool down road.
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What are the lighting problems in tunnels?
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On entering a tunnel, a driver has to make a transition between the daylight which is about 4,000 times as bright as a well-lighted highway at night.
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Name five of the devices used in monitoring tunnel safety.
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Guards, television cameras, various sensors such as carbon monoxide sensors report readings back to the control room, ultra-sonic sensors, and radios.
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Why are traffic jams are much easier to develop in tunnels than on the road? How to break a tunnel
traffic jam? |
Traffic jams are much easier to develop in tunnels because drivers drive with much more caution. The strategy for this is simply to stop traffic altogether at the entrance portal, by not releasing a new platoon of cars until they can get through the entire tunnel without reaching the trailing end of the jam.
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Name four different types of mines?
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Pit mines, strip mines, underground mines, coal mines, hard-rock mines, and open (quarry) mines.
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Describe placer mining. What is its major disadvantage?
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Placer is a technique trying to recover loose flakes from a larger portion of soil. Using sievs to wash a lot of soil to recover a few flakes. Disadvantages is that it destroys the landscape around the area. All the wash may leach into local landscapes and rivers.
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Describe the difference between open-pit mine and underground mine.
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Underground mines are mainly out of sight while open pit mines can be seen. Open uses very large machinery to scrape the surface of shallow material. Underground mining means we must drill/dig shaft to get down to where material is, then mine it out.
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What is hydraulicking? Why was it outlawed in the US?
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uses a big nozzle with a high-pressure hose that washes material from an embankment. They are outlawed because it washes land into rivers and disturbs the ecological cycle of surrounding areas.
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What are the sheaves and skips in a head frame mining operation?
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Sheaves are large pulleys at the top of the headframe and skips are ore-carrying buckets
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Name four of the methods of ore transportation.
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Conveyer belts, rail cars, cart or bin on a rail track, long line of buckets carrying materials called bucket chains, hoppers, also hauling trucks.
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Describe buffering in a mining operation. How well does it serve the mining operation?
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Is a large pile of excess rock in between the mine and the mill. If either one of them shuts down production can still happen because of the excess. It serves mining operating very well because there is never stoppage time, always enough supply.
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Name two important amenities underground mines cannot operate without. Why are they necessary?
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Ventilation and drainage, to keep air quality good and keep oxygen flow. Drainage so that water does not build up.
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How deep can a mine go? What are the problems associated with increasing depth?
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Currently the deepest is 13,000 but working on 16,000 ft. At these depths pressure, less oxygen, and heat are problems. Today there is a 16,000 ft deep shaft and the next will be 18,000.
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Name and describe the two main types of surface mines.
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Open pit- works on mineral veins and ore bodies that run deep into the ground.
Open cast (strip mining)- works better with bedded sedimentary (horizontally laid out sediments). |
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Define benches and faces in an open pit mine.
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Benches are flat platforms in a mine where machinery can stand, trucks run, while faces are vertical walls between benches.
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What is the most challenging task in forming the cascading shape of an open pit mine?
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The biggest challenge is keeping the slopes stable for trucks to drive in and out. Stable and designed in a way that the loaded heavy trucks can climb up the road.
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Name three types of explosives used in mining operations.
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Ammonium nitrate fuel oil, dynamite, and black (gun) powder
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Name and describe three patterns used in building roads in an open pit mine.
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Switch back, different ramps for loaded trucks than non-loaded trucks (out-gentle, in-steep), and circular clockwise and counter-clockwise
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Although it restores the landscape after the mining operation, open cast strip mining is not favored by
environmentalists. Why? |
It takes up so much space and is difficult to restore to its natural environment.
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The land should be restored to its “approximate original contour” after a strip mining operation. What does
this process entail? |
It needs to be leveled and graded, scraped with heavy machinery, mulch, fertilizer, and topsoil need to be laid down seeded with plants, and watered.
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How many tons of 1% ore should be mined to obtain 1 ton of metal? How does the percent of metal in the
ore impact the waste volume? |
With 1 percent ore you have to mine 100 tons of metal and leave 99 tons of waste. A lower percentage of ore means more waste.
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Explain the process of solution mining.
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Solution mining is putting sulfuric acid on a pile of rocks and letting it percolate through and collecting the leachate. Final solution is called pregnant liquor. Used to collect copper. Pregnant liquor means it carries copper, keep repeating cycle until no signs of pregnancy/copper exists, called barren liquor. Can take several years.
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What does black lung refer to?
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Breathing in coal dust in coal mines.
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Name three methods for cutting stone.
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A wire saw, a channeling machine(using fire torch), drilling with diamond tip drill bits.
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How is crushed stone produced? How are the dimensions checked?
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Crushed stone is blasted then the broken stone is pulled up through a loader or power tool then sieves/screens are used to sort the sizes.
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Name three uses of crushed stone.
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Road bed, asphalt, and concrete, also filters.
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Describe the relationship between quarries and urban sprawl.
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Quarries are first built and then neighborhoods are built in the surrounding areas, which cause conflict from the noise, dusts, and aesthetic. Quarry needed to build city, then city folk do not like it, uneasy situation.
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How is dimension stone mined?
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Chipping it off the wall of a quarry in accurate dimensions. Drill holes and insert dry wood and then wet the wood, expansion of wood cracks the stone, then push deeper and wet wood cracks stone further.
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For many centuries dimension stone was humanity’s most important building material. Explain.
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Large old structures are built of dimension stone such a cathedrals and pyramids, it lasts very long and can be cut without high tech tools. They didn’t have the technology that we have today to make molded bricks, concrete, and steel,
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How is dimension stone transported out of the mine?
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It is lifted by derricks and jib cranes.
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Describe the process of brick making.
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Clay and water is mixed together and packed into a wet clay mold, they are sliced from an extruded ribbon of clay by a fine wire. Dried under sun or oven with temperatures and pressures
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What is the difference between cement and concrete?
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Cement is a gray powder mixed with water while concrete is cement with crushed stone. Cement is part of concrete. Concrete is stone, sand, binder (cement), and water.
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Why do concrete truck drivers seem to be always in a hurry?
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So that the concrete doesn’t set in the truck.
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How does a concrete truck work?
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It spins the concrete rapidly in a clockwise direction to mix and slow to agitate material so it doesn’t set. When it is ready to dump, the helical blades and drum spin counter-clockwise and push concrete out.
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What are the solid ingredients used in making concrete? What happens to the water used in the mixture?
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Limestone and clay are dehydrated and crushed. Then when the water is mixed in a chemical process occurs that binds them together making concrete strong.
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What are the ingredients used in making hot mix asphalt? Why is it necessary to heat these ingredients
before making the mix? |
Crushed stone and gravel are held together by a tarry glue called bitumen (liquid asphalt). It is necessary to heat them so the bitumen can flow freely over the stone and gravel to coat it then harden. We heat it to make sure it doesn’t absorb the heat of the liquid asphalt.
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What is a concentrator? Describe the process of beneficiation.
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A concentrator is a mill, beneficiation is a process of enriching ore to reduce waste going to the smelter.
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Froth floatation is the most popular method of ore milling. Describe each step in this method
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Ore particles float to the top of a water tank while gangue sinks to the bottom. Tiny bubbles float to the top of the tank, which attach to the ore causing them to rise to the top. They use pine oil to generate air bubbles.
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Milling and smelting are two different mining operations. Briefly describe both.
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Milling is a physical process while smelting is a chemical process where the metal is roasted out of the ore at a high temperature, limestone is used as flux agent to consolidate materials.
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Name an undesired by-product of the smelting operation. Why is it undesired?
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Sulfur is an undesired product, it is illegal to emit into atmosphere, harmful effects to the environment because it causes acid rain.
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Describe the “make-lemonade” strategy in a smelting operation.
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It is where sulfuric acid is captured and sold as a by-product.
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Where are North American Iron sources clustered?
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Clustered around Lake Superior.
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Taconite is an iron ore that is challenging to mine and to mill. Why?
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It is too powdery to be in a furnace, if it is then it will damage the furnace. It is a very hard and abrasive rock.
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Mining and enrichment of taconite are problematic. How are these problems overcome?
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Taconite can be separated magnetically. They can press tiny grains together to make them a little larger in size, like marbles or peas, and then can be put into smelter and purified. Jet piercing torch pg 50.
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Roughly, what is the recipe for making iron?
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The recipe for iron is 3 cups of taconite, to 1 cup of coke coal, to 1 cup of limestone.
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Oxygen plays two conflicting roles in smelting copper and iron. Explain.
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It is conflicting because it is needed to separate the sulfur from the metal but oxygen needs to be separated from the metal. a seducer needs to be used to remove it. Carbon lures sulfur to attach and carbon draws in oxygen.
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What is the difference between iron and steel?
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Steel is iron without carbon. Iron is more brittle than steel.
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The steel recycling operation in minimills does not require coke or limestone. Why?
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They melt down old iron and reroll it so it has all the products in the iron. Coke is there for high heat value and limestone as flux material. The old steel is more pure and is recycling an already clean material.
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Name the ore used to produce aluminum. What is the major type of power needed for aluminum
production? What is the key operation necessary in aluminum production? |
Bauxite is used to produce aluminum metal. Hydroelectricity is major type of power used to produce it. Electricity is used to separate aluminum and oxygen.
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What can be mined from air?
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oxygen and nitrogen primarily
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To mine air, refrigeration to 300-320 degrees F below zero is required. Why?
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That is when gas is at its boiling point
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Fill in the spaces: When a gas is ________, it heats up; when the same gas is allowed to ________, it
cools off. |
compressed, expand
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What is the function of drilling mud?
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Drilling mud cools and lubricates the drill bit, carries out the cuttings of the bit, and seals the joints of the strings
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What are the functions of the drill string and the kelly?
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Drill string connects the force from the motor to the drill bit to convey torque. The kelly is a fitting that extends the drill cable to turn the bit.
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Despite the application of a pushing down vertical force, the string does not buckle. How is this achieved?
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The string remains under tension the whole time so it does not buckle, it advances one pitch per revolution.
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Describe the process of tripping in.
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Putting a drill back into the ground
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Describe the difference between top-drive motor and a down-hole motor in drilling operations.
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Top-drive motor- on top of a platform above ground that uses a string to connect it down into the ground.
Down-hole motor- down in the hole on top of the bit, which is run on compressed air. |
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How can drilling mud be densified?
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Adding barite can densify it
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What is the purpose of the doghouse on the main deck of the rig?
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Office on top of the deck which acts as a lunch room
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What is a gusher?
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When large amounts of oil spew from the ground like in the movies.
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Describe the lines of defense against blowout.
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There is a series of valves at the top of the well, which will close if any oil is sensed coming back up the well. There is also a ram preventer which crushes the pipes if the valves fail as a back up.
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What is the average production rate of an oil well in the United States?
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The average production is 11 barrels of oil per day per well
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Why is well stimulation/fracking sometimes needed?
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It is sometimes needed to keep the flow of the oil coming up out of the well when the pressure begins to decrease enough.
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Name the methods used to open up the passages through rock formations to facilitate oil extraction. How are they held open?
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Rock openings are created through high water pressure, explosions, or acids. Spherules are pumped into the holes, which are made of proppant.
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What does a Christmas tree in the oil industry refer to?
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Valves that control oil and gas out of the earth to regulate flow, pressure, take samples, and provide an emergency shutoff. Valves higher on the Christmas tree regulate flow through the central tubing while valves lower on the Christmas tree give access to space between tubing and well casing.
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Offshore drilling platforms may be floated to the drilling site. How are they mounted where drilling is to take place?
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In shallow waters they are mounted by 3 or 4 legs that come out from the bottom of the rig and lock in place on the ocean floor.
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How are floating barges and semisubmersible rigs kept in position while drilling in the sea?
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If the water is deeper there are sensors on the rig, which keep it in place accounting for movements of the ocean.
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What is the function of a sucker-rod pump?
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Pulls oil out of the well when there is no longer enough pressure to push the oil out. A steel rod is used in a rocking motion to push and pull the oil out of the well.
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What is the main function of the nodding horse-like head of the sucker-rod pump?
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The main function is to convert linear motion to vertical motion so that oil can be pumped out of the well.
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Most sucker-rod pumps run intermittently. Why?
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This avoids distorting the distribution of oil, water, and gas in the under ground formations.
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What does field processing entail? How is it achieved?
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Separating oil, gas, and salt water, a settling tank is used to separate gas at the top then oil then salt water.
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Heavy, light, sweet, and sour are crude oil varieties. What do these names refer to?
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Heavy is more viscous, tarry and dense compared to light and sour has more sulfur than sweet.
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