Nevada A-19B Pipelines and Conduits for Gas Contractor Examination

What does MAOP stand for on a natural-gas transmission or distribution pipeline?

• AMaximum Allowable Operating Pressure
• BMinimum Approved Operating Procedure
• CMeasured Average Outlet Pressure
• DMaximum Authorized Overpressure Point

Which federal regulation contains the minimum safety standards for transporting natural and other gas by pipeline?

• A40 CFR Part 280
• B29 CFR 1910.120
• C49 CFR Part 192
• D49 CFR Part 195

Under 49 CFR 192.5, a Class 1 location is a class-location unit that has how many buildings intended for human occupancy?

• AMore than 10 but fewer than 46 buildings
• B46 or more buildings
• C10 or fewer buildings
• DAny area with a four-story building

What is the minimum cover, in normal soil, for a buried gas transmission line in a Class 1 location under 49 CFR 192.327?

• A18 inches
• B24 inches
• C30 inches
• D48 inches

What minimum cover, in normal soil, is required for a buried gas transmission line in a Class 3 location?

• A24 inches
• B30 inches
• C36 inches
• D42 inches

Except where a state or local rule allows less cover with extra protection, what is the minimum cover for a buried gas distribution main?

• A12 inches
• B18 inches
• C24 inches
• D36 inches

Why is a tracer wire or equivalent locating device installed with buried plastic gas pipe?

• ATo carry cathodic-protection current to the plastic wall
• BTo provide an electrically locatable path so the nonmetallic pipe can be found later
• CTo increase the hoop-stress rating of polyethylene pipe
• DTo serve as the required grounding electrode for the gas meter

What is the primary purpose of an external coating on buried steel gas pipe?

• ATo raise the specified minimum yield strength of the steel
• BTo electrically isolate the pipe from the soil and reduce corrosion current
• CTo replace the need for a strength pressure test
• DTo increase the internal flow capacity of the pipe

What is the purpose of cathodic protection on a buried coated steel gas pipeline?

• ATo heat the pipe so wax and moisture cannot form hydrates
• BTo make the steel surface a cathode so soil-side corrosion is suppressed
• CTo raise MAOP above the design pressure
• DTo replace coating on the entire pipeline

What does SMYS mean when selecting steel pipe grade for a gas pipeline?

• ASpecified Minimum Yield Strength
• BStandard Measured Yearly Stress
• CSafe Maximum Yield of Steel
• DSeam Mill Yield Specification

Why is odorant added to most natural-gas distribution systems?

• ATo raise the heating value of the gas
• BTo give the otherwise nearly odorless gas a distinctive smell so leaks can be detected
• CTo prevent internal corrosion in steel mains
• DTo increase the MAOP of polyethylene services

What design factor F is used in the steel-pipe design formula for a Class 1 location under 49 CFR 192.111 and ASME B31.8?

• A0.40
• B0.50
• C0.60
• D0.72

What steel-pipe design factor applies in a Class 3 location?

• A0.72
• B0.60
• C0.50
• D0.40

What design factor applies to steel gas pipe in a Class 4 location?

• A0.72
• B0.60
• C0.50
• D0.40

A one-mile class-location unit contains 28 dwelling units intended for human occupancy. What class location is that unit?

• AClass 1
• BClass 2
• CClass 3
• DClass 4

A gas transmission line lies 80 yards from a playground that is occupied by more than 20 people on a normal use day. The one-mile unit otherwise has only 8 houses. What class location applies?

• AClass 1, because there are fewer than 10 houses
• BClass 2, because a playground always creates Class 2
• CClass 3, because the line is within 100 yards of that outdoor gathering place
• DClass 4, because children occupy the playground

The steel-pipe design formula in 49 CFR 192.105 and ASME B31.8 is P = (2 S t / D) × F × E × T. What does the term 2 S t / D represent?

• AThe Barlow hoop-stress design pressure before location, joint, and temperature factors
• BThe hydrostatic test duration in hours
• CThe soil-cover depth in inches
• DThe weld-acceptance limit in API 1104

For a new steel gas transmission segment that will operate at a hoop stress of 30 percent of SMYS or more, how long must the post-installation strength test hold at or above the required test pressure?

• A10 minutes
• B1 hour
• C4 hours
• D8 hours

For steel pipe installed after November 11, 1970, what minimum pressure-test factor (test pressure divided by this factor sets MAOP) applies in a Class 3 location?

• A1.10
• B1.25
• C1.40
• D1.50

A new Class 3 steel gas transmission line will have an MAOP of 720 psig. What is the minimum strength-test pressure implied by a 1.50 test factor?

• A792 psig
• B900 psig
• C1,080 psig
• D1,440 psig

Under NFPA 30 (2018) section 27.7, unless the piping is tested to ASME B31, what hydrostatic test pressure is required before flammable- or combustible-liquid piping is covered or placed in use?

• A100 percent of the maximum anticipated pressure
• B110 percent of the maximum anticipated pressure
• C150 percent of the maximum anticipated pressure
• D200 percent of the maximum anticipated pressure

NFPA 30 (2018) 27.7.1.2 sets what absolute minimums for an initial piping pressure test?

• A1 psi at the low point, held 5 minutes
• B5 psi at the highest point, held not less than 10 minutes
• C15 psi at the pump, held 30 minutes
• D50 psi at the tank, held 1 hour

Under NFPA 30 (2018), a liquid with a closed-cup flash point below 73°F and a boiling point at or above 100°F is classified as which of the following?

• AClass IA flammable liquid
• BClass IB flammable liquid
• CClass II combustible liquid
• DClass IIIA combustible liquid

In NFPA 30 (2018), what closed-cup flash-point threshold separates a flammable (Class I) liquid from a combustible (Class II or III) liquid?

• A73°F (22.8°C)
• B100°F (37.8°C)
• C140°F (60°C)
• D200°F (93°C)

What is the minimum leak-test pressure for a plastic gas pipeline under 49 CFR 192.513?

• AThe operating pressure only
• B90 psig in every case
• CAt least 150 percent of maximum operating pressure or 50 psig, whichever is greater
• DThree times MAOP, with no upper limit

A metallic (non-plastic) gas service line will operate at 60 psig. What is the minimum leak-test pressure under 49 CFR 192.511?

• A10 psig
• B50 psig
• C90 psig
• D150 percent of 60 psig (90 psig) is optional; 60 psig is enough

What is a holiday survey on newly coated steel gas pipe?

• AA visual check that every weld has a heat-number stamp
• BAn electrical inspection that finds pinholes and other coating defects before burial
• CA 24-hour outage taken on a federal holiday
• DA soil-resistivity test used to size rectifier current

A class-location unit used to classify a gas pipeline is how long, and how far does it extend from the pipeline centerline?

• A1,000 feet long and 50 feet on each side
• BOne mile long and 220 yards (660 feet) on each side
• CFive miles long and 100 yards on each side
• DThe entire county and 1,000 feet on each side

When should newly installed flammable- or combustible-liquid piping be pressure-tested under NFPA 30 (2018) 27.7.1?

• AAfter the trench is fully paved, so the pipe cannot move
• BBefore the piping is covered, enclosed, or placed in use, unless it was tested to ASME B31
• COnly after the first year of service
• DOnly if the authority having jurisdiction requests a test

What is the purpose of an isolating joint or isolating flange on a coated, cathodically protected steel gas pipeline?

• ATo electrically separate the protected pipe from unprotected structures so CP current is…
• BTo increase the hoop-stress rating at the flange
• CTo serve as the only block valve on a transmission line
• DTo bond the gas pipe to the electric-utility neutral

Calculate the design pressure of API 5L X52 pipe, 12.750-inch OD, 0.250-inch wall, Class 1 (F = 0.72), longitudinal-joint factor E = 1.00, temperature derating T = 1.00. Use P = (2 S t / D) × F × E × T with S = 52,000 psi.

• A1,020 psig
• B1,250 psig
• C1,468 psig
• D2,039 psig

A new Class 1 steel transmission line will have an MAOP of 640 psig. Using the 1.25 test factor, what minimum strength-test pressure is required?

• A704 psig
• B800 psig
• C960 psig
• D1,280 psig

A flammable-liquid pipeline has a maximum anticipated pressure of 80 psi. What NFPA 30 (2018) hydrostatic test pressure is required, and what pneumatic alternative is permitted?

• A80 psi hydrostatic or 80 psi pneumatic
• B88 psi hydrostatic or 120 psi pneumatic
• C120 psi hydrostatic or 88 psi pneumatic
• D160 psi hydrostatic or 160 psi pneumatic

A 12.750-inch-OD gas transmission line will be laid in a Class 3 location in normal soil. The design invert is 4.50 feet below finished grade. What is the cover over the top of the pipe, and does it meet 192.327?

• A3.44 feet (41.3 inches); it meets the 36-inch Class 3 soil-cover rule
• B4.50 feet (54 inches); invert depth is the same as cover
• C2.50 feet (30 inches); it meets only the Class 1 rule and fails Class 3
• D1.00 foot (12 inches); additional protection is always required

If air or inert gas is used as the test medium, what is the maximum hoop stress, as a percent of SMYS, allowed in a Class 3 location under 49 CFR 192.503(c)?

• A80 percent of SMYS
• B75 percent of SMYS
• C50 percent of SMYS
• D30 percent of SMYS

A Class 1 steel gas line crosses a hard-surfaced public highway without a casing. What design factor must be used in the 192.105 formula for that crossing?

• A0.80
• B0.72
• C0.60 or less
• D0.40

In a Class 1 or Class 2 location, a new steel pipeline that will operate at 30 percent of SMYS or more passes within 300 feet of a building intended for human occupancy. What additional 192.505 testing rule applies to that nearby segment?

• ANo special rule; the ordinary Class 1 air test is enough
• BA hydrostatic test to at least 125 percent of maximum operating pressure on that nearby s…
• CA 10-minute soap-bubble test at 5 psi
• DA pneumatic test to 200 percent of MAOP

Under NFPA 30 (2018), underground steel piping for flammable or combustible liquids must be protected against external corrosion. Which method meets that intent?

• ALeaving mill scale as the only coating because steel is thicker underground
• BApplying a suitable protective coating and, where required, cathodic protection or using…
• CWrapping the pipe with building paper after backfill
• DPainting the pipe with latex after the trench is paved

Which standard is the primary workmanship and qualification document for welding steel gas transmission and distribution pipelines?

• AAWS D1.1 only, with no pipeline alternative
• BAPI Standard 1104, Welding of Pipelines and Related Facilities
• CASME Section VIII, Division 1
• DNFPA 30 Chapter 27

In pipe welding, what is the 5G position?

• APipe axis vertical, pipe not rotated
• BPipe axis horizontal, pipe rotated while welding
• CPipe axis horizontal and fixed; the welder welds around the joint
• DPipe axis at 45 degrees, pipe not rotated

Why is a 6G welder-qualification test commonly used for pipeline and piping welders?

• A6G is the easiest position and saves coupon cost
• BThe 45-degree fixed pipe includes flat, horizontal, vertical, and overhead welding and qu…
• C6G is required only for socket welds on tubing
• DA 6G coupon replaces the need for a welding procedure specification

On a typical cellulose SMAW pipeline girth weld, which electrode is most commonly used for the open-root pass?

• AE7018
• BE6010
• CE308-16
• DE9018-B3

What is the first inspection performed on every completed pipeline girth weld?

• AHydrostatic burst to failure
• BVisual examination of the weld face, root, and adjacent pipe
• CEddy-current inspection of the coating
• DBrinell hardness of the base metal only

Why are E7018 low-hydrogen electrodes often specified for fill and cap passes on higher-strength or restrained pipeline welds?

• AThey introduce more hydrogen to keep the puddle fluid
• BThey deposit a low-hydrogen weld metal that reduces hydrogen-assisted cracking
• CThey are the only electrodes that can make an open root downhill
• DThey eliminate the need for any preheat on every grade

Under 49 CFR 192.229, a welder who welds on pipe that will operate at a hoop stress of 20 percent of SMYS or more must have had a weld tested and found acceptable under API 1104 how often?

• AOnce in a lifetime after the original qualification
• BWithin the preceding 6 calendar months, or at least twice each calendar year at intervals…
• COnly after a reportable incident
• DEvery 10 years with a written quiz

Which weld discontinuity is never acceptable under API 1104 workmanship criteria?

• AA crack of any length in the weld or heat-affected zone
• BWeld reinforcement within the height limit of the standard
• CA single isolated pore smaller than the porosity chart allowance
• DUndercut shallower than the depth allowed for that wall thickness

What is incomplete fusion in a pipeline girth weld?

• AWeld metal that failed to melt together with the groove face, previous bead, or landing
• BA coating holiday next to the weld
• CExcess weld metal above the pipe surface
• DA correctly consumed root face