NGA 15 (B) - Installing, Replacing, and Testing Electrical
Isolation Couplings Questions With Complete Solutions
_________ and ________ should be considered when selecting
the proper gasket for Flange installation Correct Answers
Flange Size, Pressure Rating of the Pipeline
A Compression Coupling that is misaligned could cause Correct
Answers A Short
A Misaligned Coupling will permit Correct Answers will
permit the pipe end to mash through the insulating sleeve, and
the coupling insulation will be shorted out.
According to DOT regulations, buried pipelines must be
Correct Answers Electrically Isolated
An insulated sleeve or washer must Correct Answers insulate
each bolt from the flange
Any broken or cracked sleeve should be Correct Answers
Replaced, because they will eventually short, rendering the
fitting ineffective
Before installing an insulator, check the Correct Answers
Pressure and Voltage Rating
Can a Flange Gasket be used more than once? Correct Answers
No, can only be used once.
, Cathodic Protection Correct Answers A technique to control
the corrosion of a metal surface by making it work as a cathode
of an electrochemical cell. This is achieved by placing in contact
with the metal to be protected another more easily corroded
metal to act as the anode.
Components of an insulating fitting Correct Answers Nut(s),
Bolt-Stud, Steel Washer, Insulating Gasket, Steel Sleeve
Consideration of the following factors to protect insulating
devices Correct Answers Pipeline carrying either unbalanced
line currents or fault currents, Lightning or fault currents
inducing voltages sufficient to puncture pipe coatings or pipe,
cathodic protection of the pipeline (including the location of
ground beds). Bonding connections that exist between the
pipeline and the overhead electric system at the steel tower
footing, or the buried ground facility, or ground wire. The
electrical properties of non-welded joints.
Current Mapper Correct Answers Used to find an electrical
short in an underground system
Di-Electric Insulating Unions Correct Answers They have a
plastic insert molded into the metal shell to provide insulation. A
rubber gasket is required to seal the faces gas tight.
ensure a new insulator is effective by checking both Correct
Answers before and immediately after being installed
Flange Insulation Requirements Correct Answers Gasket of
high dielectric strength and flexibility. Must be able to withstand
Isolation Couplings Questions With Complete Solutions
_________ and ________ should be considered when selecting
the proper gasket for Flange installation Correct Answers
Flange Size, Pressure Rating of the Pipeline
A Compression Coupling that is misaligned could cause Correct
Answers A Short
A Misaligned Coupling will permit Correct Answers will
permit the pipe end to mash through the insulating sleeve, and
the coupling insulation will be shorted out.
According to DOT regulations, buried pipelines must be
Correct Answers Electrically Isolated
An insulated sleeve or washer must Correct Answers insulate
each bolt from the flange
Any broken or cracked sleeve should be Correct Answers
Replaced, because they will eventually short, rendering the
fitting ineffective
Before installing an insulator, check the Correct Answers
Pressure and Voltage Rating
Can a Flange Gasket be used more than once? Correct Answers
No, can only be used once.
, Cathodic Protection Correct Answers A technique to control
the corrosion of a metal surface by making it work as a cathode
of an electrochemical cell. This is achieved by placing in contact
with the metal to be protected another more easily corroded
metal to act as the anode.
Components of an insulating fitting Correct Answers Nut(s),
Bolt-Stud, Steel Washer, Insulating Gasket, Steel Sleeve
Consideration of the following factors to protect insulating
devices Correct Answers Pipeline carrying either unbalanced
line currents or fault currents, Lightning or fault currents
inducing voltages sufficient to puncture pipe coatings or pipe,
cathodic protection of the pipeline (including the location of
ground beds). Bonding connections that exist between the
pipeline and the overhead electric system at the steel tower
footing, or the buried ground facility, or ground wire. The
electrical properties of non-welded joints.
Current Mapper Correct Answers Used to find an electrical
short in an underground system
Di-Electric Insulating Unions Correct Answers They have a
plastic insert molded into the metal shell to provide insulation. A
rubber gasket is required to seal the faces gas tight.
ensure a new insulator is effective by checking both Correct
Answers before and immediately after being installed
Flange Insulation Requirements Correct Answers Gasket of
high dielectric strength and flexibility. Must be able to withstand
