Threaded and Grooved Pipe

Question 1

What does the following abbreviation stand for: Std?

Answer 1

Standard

Question 2

What does the following abbreviation stand for: XS

Answer 2

Extra Strong

Question 3

What does the following abbreviation stand for: XXH

Answer 3

Double Extra Heavy

Question 4

What does the following abbreviation stand for: XH

Answer 4

Extra Heavy

Question 5

What does the following abbreviation stand for: XXS

Answer 5

Double Extra Strong

Question 6

What does the following abbreviation stand for: Sch

Answer 6

Schedule

Question 7

What is the difference between inside diameter and nominal pipe size?

Answer 7

ID is the actual measurement between the inside walls of the pipe across the exact center. NPS is an approximation of the inside diameter; it is an industry standard used to identify various pipe sizes.

Question 8

What is the difference between black iron pipe and galvanized pipe?

Answer 8

Black iron pipe - shellac or varnish applied for protection.
Galvanized iron pipe - zinc coating applied by hot dipping the black pipe.

Question 9

Which grade of threaded pipe should be used with 150psi maximum pressure?

Answer 9

Std/Sch40

Question 10

Which grade of threaded pipe should be used with 200psi maximum pressure?

Answer 10

XS/Sch80

Question 11

Which grade of threaded pipe should be used with 1000psi maximum pressure?

Answer 11

XXS

Question 12

What is the approximate percent of carbon in the iron used to produce steel pipes?

Answer 12

0.1 to 0.2% carbon

Question 13

What is the approximate percent of carbon in the iron used to produce files?

Answer 13

1.5% carbon

Question 14

What is the approximate percent of carbon in the iron used to produce cast iron?

Answer 14

1.8 to 4.8% carbon

Question 15

What is the approximate percent of carbon in the iron used to produce sheet steel?

Answer 15

0.1 to 0.2% carbon

Question 16

What does the schedule number of a pipe designate?

Answer 16

The pressure/stress ratio X 1000

Question 17

At what size for standard pipe does the wall thickness remain the same for increases in pipe size and what is the WT?

Answer 17

Size = 12”
WT = 0.375”

Question 18

What is meant by the word alloy as applied to the manufacture of ferrous pipe?

Answer 18

Alloys are metals mixed with iron to produce special qualities in pipe.

Question 19

List three different types of alloyed steel pipe and state the alloying materials used?

Answer 19

Copper bearing alloys - min 0.25% copper
Stainless steel - chromium and nickel
Chrome/moly - chromium and molybdenum

Question 20

What are common surface finishes applied to steel pipe?

Answer 20

Plain End
Bevelled End
Threaded
Threaded and Coupled
Grooved

Question 21

What are common surface finishes applied to steel pipe before delivery?

Answer 21

Laquered
Asphalt/Bitumen
Yellow Jacket
Galvanized
Pickled and Oiled
Painted

Question 22

What is the distance called from the crest of one thread to the crest of the next thread called?

Answer 22

Pitch of the thread.

Question 23

What is the difference between male and female threads?

Answer 23

Male threads are on the external or outer surface of the pipe.
Female threads are internal or inner surface surface of the fitting.

Question 24

What is the thread on the inside wall of a fitting referred to as?

Answer 24

The thread on the inside wall of a fitting is referred to as a female tapered thread or FIP (female iron pipe thread).

Question 25

When tightening a fitting onto a pipe, the fitting should be turned by hand approximately ______ to ______ times and made up with the aid of a wrench approximately _____ to _____ turns?

Answer 25

When tightening a fitting onto a pipe, the fitting should be turned by hand approximately 4 to 6u times and made up with the aid of a wrench approximately 2 to 3 turns.

Question 26

Why are pipe threads tapered and how much does this taper amount to if extended to one foot in length?

Answer 26

Pipe threads are tapered so that the pipe will tighten into fittings. The taper amount is %¼" increase in diameter at 12".

Question 27

Define the term throw as it applies to pipe fittings?

Answer 27

The distance measured from the centre to the face of fittings.

Question 28

What are different methods of taking pipe measurements?

Answer 28

Centre to centre - C. to C. End to end - E. to E. End to end overall - E. to E. overall End to centre - E. to C. Centre to face - C. to F. Face to face - F. to F.

Question 29

What is the difference between coupling and thread protector?

Answer 29

Couplings have tapered threads; thread protectors have parallel threads.

Question 30

List four reasons for flushing oil over a pipe thread that is being cut.

Answer 30

To cool the chasers (dies) and pipe. To flush out the swarf (chips). To lubricate. To provide a good finish.

Question 31

Burs should be removed from the inside walls of pipe. List thre (3) problems that can occur if burrs are not removed.

Answer 31

Pressure loss due to increased flow restriction. Localized erosion due to turbulent flow. Pipe blockage caused by material hanging up on the burr.

Question 32

If a galvanized pipe is threaded, is the thread protected by the galvanizing? Explain your answer.

Answer 32

No; the zinc or galvanizing coating is removed from the pipe's outer surface by threading and from the internal surface by reaming.

Question 33

Describe the accepted procedure for making threaded joints.

Answer 33

a) Measure. d) Ream. b) Mark. e) Oil and thread. c) Cut. d) Clean, apply compound, and tighten.

Question 34

Why is jointing compound applied to pipe threads when you are making threaded joints?

Answer 34

Lubrication allows better tightening.

Question 35

When making threaded joints, to which thread should you apply the jointing compound? Why?

Answer 35

It should be applied to the male thread only so that the compound is prevented from entering into the piping system.

Question 36

Which reamer is best suited for use with hand operations only, not to be used with a power vise?

Answer 36

Spiral fluted reamer are to be used by hand operation only.

Question 37

Which hand reamer can be used with either a power vise or a hand operation?

Answer 37

Straight fluted reamer may be used by hand or on power equipment.

Question 38

What type of lubricating oil you would use on copper pipes when cutting threads?

Answer 38

Mineral oil, lard/tallow.

Question 39

What type of lubricating oil you would use on stainless steel pipes when cutting threads?

Answer 39

High sulphur content oil.

Question 40

What type of lubricating oil you would use on brass pipes when cutting threads?

Answer 40

Soapy water.

Question 41

What type of lubricating oil you would use on steel or wrought iron pipes when cutting threads?

Answer 41

Thread cutting oil.

Question 42

What are fittings used for?

Answer 42

Fittings are used to add branches for changes in direction or to connect sections of a piping system.

Question 43

Name the methods of joining pipe.

Answer 43

Threaded Grooved. Flanged Compression - dresser fittings. Welded. Press connect.

Question 44

The two (2) main types of steel pipe cutters are: Name an advantage of each. Name a disadvantage of each.

Answer 44

Single-wheel - small outer burrs only - requires a full 360° turn. Multi-wheel - used in tight places - large outer burrs; may spiral on pipe.

Question 45

What effect does a ridge that forms on the outside of the pipe after cutting have on later operations and how is the ridge removed?

Answer 45

Can cause dies to be hard to start, remove with a file.

Question 46

The first thread cut by the dies is the ____________ thread cut because of the designed taper of the thread.

Question 47

As the size of the pipe increases, the number of threads cut per inch generally?

Answer 47

decreases

Question 48

The first thread cut by the dies is the ____________ thread cut because of the designed taper of the thread.

Answer 48

deepest

Question 49

Cutting a shallower thread rather than a standard thread will make the fitting ___________ to start.

Answer 49

harder

Question 50

All pipe fittings have a/an __________ thread.

Answer 50

tapered

Question 51

Standard threads are all __________ hand threads.

Question 52

When screwing on a fitting, it must be turned?

Answer 52

clockwise

Question 53

Impertect or torn pipe threads can result in ___________ joints.

Question 54

Threading a pipe that has been cut with a cutting torch will __________ athe life of the die chasers.

Answer 54

shorten

Question 55

Impertect or torn pipe threads can result in ___________ joints.

Answer 55

leaking

Question 56

Standard threads are all __________ hand threads.

Answer 56

right-hand

Question 57

The thread applied to a pipe or a fitting is a/an __________ thread.

Answer 57

tapered

Question 58

The difference between perfect and imperfect threads is that they are __________ on the top or top and bottom.

Answer 58

imperfect

Question 59

Applying insufficient oil when cutting threads will result in __________ threads.

Answer 59

torn or broken

Question 60

Improperly adjusted dies will result in __________ a thread.

Answer 60

too loose or too tight