Test 1 Flashcards
- NPS is an acronym for ______.
Nominal Pipe Size
- T/F Pipes were originally produced to have one thickness which was termed standard (STD).
True
- When pipes were manufactured with thicker walls they became known as extra _________ or extra __________.
strong, heavy
- T/F As pipes were manufactured with thicker walls, the outside diameters remained unchanged.
True
- The term ____ was invented to specify the nominal wall thickness of pipe.
schedule
- The NPS is loosely related to the _______diameter of the pipe.
inside
- For a given NPS, the pipe _______ diameter stays constant.
outside
- Larger schedule numbers mean ________ pipe wall thickness.
thicker
- Name the two non-dimensional numbers used to specify pipe.
Nominal Pipe Size (NPS) & schedule number (SCH)
- For pipe sizes larger than _____ inch, the NPS corresponds to the actual outside diameter.
12
- Schedule 80 pipe provides a _________ factor of safety compared to a similar size Schedule 40 pipe.
greater
- Schedule 80 pipe costs ____ compared to a similar size Schedule 40 pipe.
more
Using the ANSI Pipe Schedule, answer the questions below.
11. For the following pipe sizes, state the pipe outside diameter:
a. 2-inch ______
b. 6-inch ______
c. 12- inch _____
d. 16-inch _____
a. 2-inch 2.375”
b. 6-inch 6.625”
c. 12- inch 12.750”
d. 16-inch16.000”
Using the ANSI Pipe Schedule, answer the questions below.
12. For the following pipe sizes, calculate the pipe inside diameter:
a. 2-inch XH _______
b. 8-inch Schedule 40 _______
c. 12-inch Schedule 40 ______
d. 20-inch Schedule 80 ______
a. 2-inch XH 2.375 - 2 x .218 = 1.939”
b. 8-inch Schedule 40 8.625 - 2 x .322 = 7.981”
c. 12-inch Schedule 40 12.750 - 2 x .406 = 11.938”
d. 20-inch Schedule 80 20.000 - 2 x 1.031 = 17.938”
Using the ANSI Pipe Schedule, answer the questions below.
13. What is the weight per foot in pounds of the following pipe sizes:
a. 2-inch XH _____
b. 10-inch Schedule 40 ______
c. 20-inch Schedule 40 ______
d. 30 -inch XH _________
a. 2-inch XH 5.03
b. 10-inch Schedule 40 40.52
c. 20-inch Schedule 40 123.23
d. 30 -inch XH 157.68
- This material is used due to its good corrosion resistance and excellent machinablility. It is used in low to medium pressure applications, commonly in residential or commercial plumbing systems.
Brass
- This material is a popular choice due to its ability to handle high temperature, high pressure operations. It is commonly used in the water, oil, and gas industries.
Carbon Steel
- This material is used in applications that involve corrosive fluids, chemicals, and environments. It is often used in food processing, pharmaceutical, and chemical.
Stainless Steel
- This material is a cost-effective material commonly used in low pressure applications. It is often used in water, steam and gas applications.
Cast Iron
- This material is used for applications that call for unique properties and are highly resistant to corrosion and extreme high temperatures. This material Is often used is chemical processing plants and nuclear power facilities.
Special Alloys
- This material is like cast iron in its composition but offers higher strength and flexibility. It is often used in water, oil, and gas applications.
Ductile Iron
- What are the two most popular methods of manufacturing valves.
Casting Method and Forging Method
- Name the six steps in involved casting.
Mold or core preparation, Metal melting, Pouring molten metal into the mold, Solidifying the metal, Removing the cast component from the mold, Finishing and polishing the component
- Name the five stages involved in forging.
Cutting and forging the metal, Trimming excess material, Sandblasting to smooth and clean surfaces, Machining to refine shape and dimensions, Surface treatment to enhance component properties
- Name two advantages of the casting process.
Suitable for high-volume production and Ideal for creating intricate valve components
10.Name two advantages of the forging process.
Improved fatigue resistance, making it suitable for heavy-duty applications and Suited for producing smaller components or low volume orders
- _______ were the first people to use valves with aqueducts.
Romans
- Name two applications that valves were used for in ancient times.
Public use or irrigation
- T/F The modern history of the valve industry starts with the Industrial Revolution.
True
- Name the four primary functions of valves.
On/off, flow control, directional flow and overpressure protection
- This valve part is the main pressure retaining part, provides the passage for fluid flow, and accommodates the valve trim.
The body
- If the inside passage diameter of the valve is the same as the connecting pipe, it is known as a _______.
Full bore
- If the inside passage diameter of the valve is smaller than the connecting pipe, it is known as a _____.
Reduced bore
- Name a type of valve end connection.
threaded
- This kind of body is used mainly in globe valves, piston or plug type check valves.
Crossflow or Split section body
- The cover for the valve body is known as a ________.
Bonnet
- T/F In a split body ball valve, there is not a bonnet because the body is split into two sections.
True
- The removable internal parts of the valve that contact the flow medium are known as the valve ___.
trim
- This part of the valve trim allows, throttles, or stops the fluid flow.
the disc
- T/F The valve leakage rate is directly proportional to the effectiveness of the seal between the valve disc and the seat(s).
true
- What is the purpose of the back seat.
Prevents leakage of flow medium to the packing chamber and consequently to the environment.
- This part of the valve connects the actuator and the disk.
the stem
- This valve part connects the valve body or bonnet with the actuating mechanism.
the yoke
- What is the stem/gland packing made of?
Graphite or Polytetrafluoroethylene (PTFE)
- Name three U. S. based organizations involved in valve standards.
American Petroleum Institute, American Society of Mechanical Engineers, American National Standards Institute
- Which ASME Standard covers Face-to-Face and End-to-End Dimensions of Valves?
Standard 16.10
- Name four valve types that are covered by this standard?
Plug, check, gate, globe
- What is the purpose of this standard?
To assure installation interchangeability for valves of a given material, type, size, rating class and end connection.
- Define the face-to-face flange dimension.
The distance between the extreme ends which the gasket surface contacts.
- Define the face-to-face flange dimension for buttwelded end valves.
The distance between the welding bevels.
- Valve size in North America is denoted by the ___________.
nominal pipe size (NPS)
- In the metric system, valve size is designated by the _________.
nominal diameter (DN) of connecting pipe or the connecting flange ends.
- T/F The valve size is not necessarily equal to the inside diameter of the valve.
True
- What is WOG an acronym for and what does it represent?
Water, Oil, Gas - represents the maximum pressure per square inch that the valve can handle at ambient temperature.
- A 200 WOG equals _______ psi.
200
- What is CWP an acronym for and what does it represent?
Cold Working Pressure - defines the maximum pressure rating for valves between -20F - 100F.
- A 150 CWP equals _______ psi.
150
- T/F Class numbers designate the pressure-temperature ratings of valves.
True
- The temperature shown for a corresponding pressure rating is the temperature of the _______ component of the valve.
Pressure-containing shell
- What class numbers are covered by ASME standard B16.34?
150, 300, 400, 600, 900, 1500, 2500, and 4500 valves
- What class numbers for steel pipe are covered by ASME standard B16.34?
150,300,600,900,1500, & 2500
- Name the two types of leaks that occur while undergoing tests.
External and Internal
- Name the two types of tests used to test for valve leakage.
Hydrostatic and/or pneumatic
- T/F The maximum allowable leakage for valves is defined by valve size.
True
- What is the most widely used standard for valve inspection & testing?
American Petroleum Institute (API) 598, Valve Inspection and Test
- _____ test confirms the soundness of the pressure containing structure within the valve.
Shell
- _____ test verifies the leakage through the stem or shaft to the seal.
Backseat
- ______ test is required for all gate, globe, plug, check, floating ball, and butterfly and verifies the leakage through the closure mechanism.
Closure
- T/F The API standard requires zero leakage for the shell test.
False No visible leakage
Using the Leakage Table in the Reading, answer questions 26 -28.
- How much liquid (drops/minute) is allowed for a 4” metal seated ball valve?
12
Using the Leakage Table in the Reading, answer questions 26 -28.
- How much gas (bubbles/minute) is allowed for a 10” metal seated plug valve?
40
Using the Leakage Table in the Reading, answer questions 26 -28.
- Per the notes, 1 milliliter is equivalent to ____ drops.
16
- What is the ISO standard for pressure testing of valves?
ISO 5208, Industrial Valves, Pressure Testing of Valves
- Name two valves that are classified as linear motion valves.
Gate and globe
- Name three valves that are classified as rotary motion valves.
Stop check valve, ball valve and plug valve