Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
52 Cards in this Set
- Front
- Back
|
Before breaking a joint or cutting into a line in any piping system, you should first take which of the following precautions?
a.) Close the stop valves b.) Tag the locked stop valve c.) Ensure that there is no pressure on the line d.) Ensure that the pipeline has not been drained |
c.) Ensure that there is no pressure on the line
|
|
|
You are making repairs to a piping system made of 70/30 cuni pipe and run out of this type of pipe. What action should you take in substituting 90/10 cuni pipe for the 70/30 cuni page?
a.) Obtain authorization from an approved authority b.) Document the substitution on a QA form 14 c.) Substitute the pipe and classify the repair as temporary repair d.) Continue the repair, since the replacement |
a.) Obtain authorization from an approved authority
|
|
|
When installing a welded pipe joint, you must leave a 1/16 to 1/8 inch end gap clearance between the fitting and the pipe end. What purpose does this gap service?
a.) It prevents corrosion of the pipe end b.) It allows for pipe extension c.) It allows for pipe contraction d.) It prevents excess fluid turbulence |
b.) It allows for pipe extension
|
|
|
In pipe fabrication and repair, templates serve what purpose?
a.) They support flange targets b.) They serve as a guide for bends and flanges c.) They determine clearance for insulation installation d,) They support pipe ends in the bending process |
b.) They serve as a guide for bends and flanges
|
|
|
When constructing a target, you should weld it with what minimum distance off the target deck?
a.) 6 in. b.) 9 in. c.) 12 in. d.) 18 in. |
c.) 12 in.
|
|
|
When making a centerline template, you should use what size metal rod?
a.) 1/8 to 1/4 in. b.) 1/4 to 3/8 in. c.) 3/8 to 1/2 in. d.) 1/2 to 5/8 in. |
b.) 1/4 to 3/8 in.
|
|
|
A centerline template is constructed for a section of new piping being installed in a piping run. To ensure that the new section of the pipe will fit, you should use (a) what item and (b) it should be made of what material?
1. (a) Clearance Disk (b) Sheet metal 2. (a) Space ring (b) sheet metal 3. (a) Clearance disk (b) plywood 4. (a) Space ring (b) plywood |
1. (a) Clearance Disk
(b) Sheet metal |
|
|
Steel, aluminum, or copper-nickel piping should NOT be bent to a radius less than how many times the diameter of the pipe?
a.) 7 b.) 2 c.) 6 1/2 d.) 4 1/2 |
b.) 2
|
|
|
What could happen if you work with a section of pipe too short for the portable pipe bender?
a.) The pipe ends could flatten b.) The pipe throat could wrinkle c.) The angle gauge could give false readings d.) The pipe could slip off the pivot shoes |
d.) The pipe could slip off the pivot shoes
|
|
|
You are using the portable pipe bender to bend a section of pipe and have repeated problems with wrinkling and out-of-roundness of the pipe after bending. What can you do to reduce or eliminate these problems?
a.) Use a larger radius bend shoe b.) Make several smaller bends c.) Use thicker pipe d.) Reduce the rate of bend |
b.) Make several smaller bends
|
|
|
Which of the following dies reduces wrinkling of the pipe throat?
a.) Bend b.) Clamp c.) Pressure d.) Wiper |
d.) Wiper
|
|
|
When setting up and adjusting the clamp die on the rotary pipe bender, what should you use as a gauge?
a.) The actual pipe to be bent b.) The gauge rods provided with the die set c.) Round stock of equal diameter d.) A sample pipe of the same diameter as the actual pipe |
d.) A sample pipe of the same diameter as the actual pipe
|
|
|
You are using a mandrel to bend a section of pipe on the rotary pipe bender. What purpose does the mandrel serve?
a.) It supports the pipe wall b.) It decreases the radius of bend c.) It increases the bending capacity of the machine d.) it prevents back wall thinning |
a.) It supports the pipe wall
|
|
|
What should be the maximum clearance between a rigid mandrel and the pipe wall?
a.) Twice the wall thickness b.) Half the wall thickness c.) 10 percent of the wall thickness d.) 20 percent of the wall thickness |
d.) 20 percent of the wall thickness
|
|
|
When using a mandrel to bend pipe, what type of lubricant should you use?
a.) Lanonlin-based b.) Petroleum-based c.) Glycerin- based d.) Graphite- based |
a.) Lanonlin-based
|
|
|
When bending a section of pipe in the rotary pipe bender, what reference mark should you watch for signs of slippage?
a.) The automatic stop b.) The angle guide c.) The pencil mark on the pipe d.) The bench mark stamped on the pipe |
c.) The pencil mark on the pipe
|
|
|
Why should you set the automatic stop a few degrees greater than the desired bend angles?
a.) To allow for pipe slippage b.) To verify accuracy of the bend angle c.) To allow for springback d.) To allow for back bending |
c.) To allow for springback
|
|
|
A pipe is packed with dry sand as a preliminary step in hot bending for which of the following reasons?
a.) To reduce the cross-sectional area of the pipe b.) To restrict the flow of fluid through the system c.) To prevent the heel or the outside of the bend from flattening d.) To prevent hot spots from developing |
c.) To prevent the heel or the outside of the bend from flattening
|
|
|
When filling a section of pipe with sand, what is the "general rule of thumb" concerning the amount of tamping required?
a.) Tamp 1/2 hour for every inch of pipe diameter b.) Tamp 1 hour for every inch-of pipe diameter c.) Tamp until you cannot leave your fingernail print in the sand d.) Tamp until the sand crystallizes |
b.) Tamp 1 hour for every inch-of pipe diameter
|
|
|
When installing a plug in the end of a pipe filled with sand, why must you drill a hole through the center of the plug?
a.) To allow water vapor to escape b.) To prevent blowing out the end of the plug c.) Both 1 and 2 d.) To prevent crystallization of the sand |
c.) Both 1 and 2
|
|
|
Pipes made from which of the following materials should be bent cold in manual or power bending machines?
a.) Aluminum b.) Carbon-molybdenum c.) Copper d.) Wrought iron |
b.) Carbon-molybdenum
|
|
|
All pipe should be inspected after bending for defect. Defects are acceptable if they do NOT exceed what maximum depth?
a.) 0.05 in. b.) 0.010 in. c.) 5 percent of the nominal thickness of the pipe d.) Either 2 or 3 above, whichever is greater |
b.) 0.010 in.
|
|
|
A bulge in a bent section of pipe can be what maximum vertical height?
a.) 3 percent of the nominal pipe OD b.) 5 percent of the nominal pipe OD c.) 3 percent of the pipe wall thickness d.) 5 percent of the pipe wall thickness |
a.) 3 percent of the nominal pipe OD
|
|
|
In figuring out-of-roundness in a bent section of pipe, the formula (OD max + OD min) + 2 determines what measurement?
a.) OD nominal b.) OD Constance c.) Percent of back-wall thinning d.) Percent of out-of-roundness |
d.) Percent of out-of-roundness
|
|
|
When threading a section of 1 1/2 inch pipe on a pipe threading machine, what setting must you check before threading operations begin?
a.) The size of the chuck assembly b.) The length of the dies c.) The depth of cut d.) The range of the dies. |
d.) The range of the dies.
|
|
|
What is the maximum length of a nipple?
a.) 6 in. b.) 10 in. c.) 12 in. d.) 16 in. |
c.) 12 in.
|
|
|
When you are applying pipe dope to a threaded joint, where should the dope be applied?
a.) To the male threads only b.) To the female threads only c.) To the upper half of the male and female threads d.) To the lower half of the male and female threads |
a.) To the male threads only
|
|
|
If the system blueprint is not available when choosing gasket material for a pipe joint, which of the following MIL-STDs should you consult?
a.) 834 b.) 727 c.) 635 d.) 438 |
d.) 438
|
|
|
In making up a plain flange joint, which of the following gasket thickness should you use?
a.) 1/2 in. b.) 1/16 in. c.) 1/4 in. d.) 5/16 in. |
b.) 1/16 in.
|
|
|
If a flange joint is made with a cork gasket, what could happen to the gasket if it is compressed to more than 70 percent of its thickness?
a.) Loss of resiliency b.) Rupture c.) Restricted flow d.) Uneven torquing |
a.) Loss of resiliency
|
|
|
When checking the compression of a spiral wound metal gasket, what instrument should you use?
a.) A micrometer b.) A dial caliper c.) A feeler gauge d.) A steel rule |
c.) A feeler gauge
|
|
|
How should you determine whether a bolt stub is overstressed?
a.) Check for microscopic cracking b.) Use a tension meter c.) Perform an ultrasonic test d.) Check bolt stud elongation |
d.) Check bolt stud elongation
|
|
|
When a swaged marine fitting is installed on a section of pipe, what maximum acceptable degree of cut, from square, is allowed?
a.) 50 b.) 20 c.) 30 d.) 70 |
c.) 30
|
|
|
To use a scriber to install inspection and insertion marks associated witht the swage marine fitting on the pipe wall, the pipe must be at least how thick?
a.) 0.012 in. b.) 0.090 in. c.) 0.110 in. d.) 0.125 in. |
d.) 0.125 in.
|
|
|
When tubing or pipe is bent, what causes flat spots?
a.) Compression b.) Stretching of the neutral axis c.) Lack of support for the pipe wall d.) Compression of the throat area |
c.) Lack of support for the pipe wall
|
|
|
When using a pipe sizing machine, how can you determine the amount of expansion for each turn of the locknut?
a.) Each turn of the locknut equals 0.001 inch b.) Each turn of the locknut equals 0.0001 inch c.) By the number stamped on the roller d.) By the number stamped on the locknut |
d.) By the number stamped on the locknut
|
|
|
What is the maximum diameter of pipe that can be expanded using a drift pin?
a.) 1 in. b.) 2 in. c.) 3 in. d.) 4 in. |
b.) 2 in.
|
|
|
After expanding the end of a section of pipe to 0.065 inch, what inspection, if any, should you perform?
a.) Dye Penetrant b.) Ultrasound c.) Visual 5X d.) none |
a.) Dye Penetrant
|
|
|
When a valve is installed in its most desirable position, the valve stem should point in what direction?
a.) Midway between straight down and vertical b.) Horizontal c.) Straight down d.) Straight up |
d.) Straight up
|
|
|
Which of the following materials should you use to spot-in a valve?
a.) Red Lead b.) Lubricating oil c.) Prussian blue d.) Lapping compound |
c.) Prussian blue
|
|
|
In a properly ground-in valve, the contact area should cover approximately what fraction of the seating area?
a.) 1/4 b.) 1/3 c.) 1/2 d.) 2/3 |
b.) 1/3
|
|
|
When using pencil marks to spot-in a valve seat that has been refaced, you should place the marks on the bearing surface of the seat at approximately what intervals?
a.) 1 in. b.) 2 in. c.) 1/4 in. d.) 1/2 in. |
d.) 1/2 in.
|
|
|
To prevent the strong packing from folding back when the gland is tightened, in what direction should you wind the packing?
a.) In the same direction that you would tighten the gland nut b.) in the opposite direction that you would tighten the gland nut c.) In the same direction the valve stem is turned to open the valve d.) in the same direction the valve stem is turned to close the valve |
a.) In the same direction that you would tighten the gland nut
|
|
|
Continuous flow through a piston-type flushing valve is caused by which of the following factors?
a.) Failure of the relief valve to open b.) A large amount of water in the upper chamber c.) Corrosion of the bypass valve d.) Excessive pressure forcing the piston to seat |
c.) Corrosion of the bypass valve
|
|
|
Short flushing can only occur in which type of flushing valve?
a.) Piston b.) Seal c.) Hydraulic d.) Diaphram |
d.) Diaphram
|
|
|
What causes a pressure reducing valve to chatter?
a.) Water supply too small b.) Fast opening and closing c.) A broken O-ring d.) A ruptured diaphragm |
b.) Fast opening and closing
|
|
|
What NSTM chapter should you consult for valve seating problems?
a.) 074, Vol IV b.) 555 c.) 505 d.) 365 |
c.) 505
|
|
|
When applying insulation, you should use which of the following precautions?
a.) Fill and seal all air pockets and cracks b.) Seal the ends of the insulation and taper off to a smooth airtight joint c.) Insulate all hangers and other supports at their point of contact from the pipe or unit they support. d.) Each of the above |
d.) Each of the above
|
|
|
Moistened insulating material will produce which of the following?
a.) Heat losses b.) A weakened insulating valve c.) Eventual disintegration d.) Both 2 and 3 above |
d.) Both 2 and 3 above
|
|
|
The knitted wire mesh used on the inside surface of insulation covers exposed to temperatures above 850 degrees F. should be constructed of what type of material?
a.) 304 Stainless steel b.) 7030 cuni c.) Galvanized steel d.) Monel |
a.) 304 Stainless steel
|
|
|
Which of the following NSTM chapters cover insulation requirements?
a.) 679 and 635 b.) 1720 and 1688 c.) 1688 and 1689 d.) 248 and 278 |
a.) 679 and 635
|
|
|
When setting pressure boundaries prior to working on a piping section, you CANNOT use which of the following valves as a barrier?
a.) globe b.) check c.) gate d.) butterfly |
b.) check
|
