4AE3.5 U3 C4 Obj 3 HARD

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

Which of the following is NOT mentioned as an outlet connection for a boiler?

Safety valve
Feedwater inlet
Main steam stop valve
Vent for flue gases (correct)

According to ASME B 31.1, which code has jurisdiction over the boiler external piping?

ASME BPVC I
ASME Sec II Part D
ASME Sec VIII Div 1
ASME B31.1 (correct)

In what scenario should the connection from each boiler having a manhole opening be fitted with two stop valves having an ample free-blow drain between them?

When two or more boilers are connected to a common header (correct)
When two or more boilers are connected to separate headers
When a single boiler is connected to a common header
When a single boiler is connected to a header with no other steam source

How can fittings and piping be attached to the boiler according to the text?

Welded directly to the drum or shell (D) Signup and view all the answers

Why does Boiler #2 require a manhole?

To allow for inspections and maintenance (B) Signup and view all the answers

Why would Boiler #1 require a block and bleed system if it had a manhole?

To connect to a common steam header (A) Signup and view all the answers

What is the requirement for the shut-off valves in the steam line according to ASME BPVC I?

They must be equipped with a position indicator (C) Signup and view all the answers

What is the requirement for each feedwater line to a boiler according to ASME B31.1?

A check valve and a stop valve (B) Signup and view all the answers

What is required in the branch to each boiler when multiple boilers are fed from a common source?

A globe or regulating valve (A) Signup and view all the answers

What is the requirement for blowoff valves on boilers with allowable working pressures over 100 psig according to ASME B31.1?

Two slow-opening blowoff valves (B) Signup and view all the answers

What is the requirement for traction and portable boilers, as well as forced circulation and electric steam boilers with a normal water content of 380 L (100 US gallons) or less, regarding blowoff valves?

One slow-opening blowoff valve (B) Signup and view all the answers

Which fittings are attached to a low-pressure steam boiler according to ASME B31.1?

Steam outlet stop valve, feedwater inlet stop and check valves, blowoff valves, vent valve, and water level controls (B) Signup and view all the answers

Where does the steam produced in the boiler leave through?

The main header (C) Signup and view all the answers

What type of valves are commonly used on the steam outlet of a boiler?

Globe valves (B) Signup and view all the answers

Where are stop valves used in connection with boilers?

In the return pipe connections of single and multiple boilers (D) Signup and view all the answers

According to ASME BPVC IV Part HG-705(a), where should feedwater not be introduced?

Through openings or connections provided for inspection or cleaning (D) Signup and view all the answers

Which type of check valve is used in the feedwater line according to ASME BPVC IV Part HG-705(a)?

Lift check valve (A) Signup and view all the answers

What is the purpose of the return (or Hartford) loop as required by ASME BPVC IV Part HG-703.2?

To prevent boiler pressure from lowering the boiler water level (C) Signup and view all the answers

What is the minimum pressure rating required for the valves used to blowoff or drain low-pressure steam boilers?

$200 kPa (30 psi)$ (C) Signup and view all the answers

According to ASME BPVC IV Part HG-715(a), why are bottom blowoff connections required to be connected to the lowest water space practicable?

To ensure complete drainage of the boiler (A) Signup and view all the answers

Why is it recommended to use outside screw and yoke valves with rising spindles when the steam outlet is DN 50 (2” NPS) or larger?

To prevent corrosion by steam or water on the spindle (B) Signup and view all the answers

What is the minimum temperature rating required for the valves used to blowoff or drain low-pressure steam boilers?

$120°C$ ($250°F$) (A) Signup and view all the answers

According to ASME BPVC IV Part HG-705(a), why should a stop valve or cock be installed either upstream or downstream of the check valve in pumped return systems?

$To prevent the boiler from draining when the boiler feedwater pump is off$ (D) Signup and view all the answers

Flashcards are hidden until you start studying

Study Notes

Boiler #1: Small steam drum, only equipped with a handhole.
Boiler #2: Larger shell, requires a manhole for inspections and maintenance.
Due to connection to a common steam header, Boiler #2 requires block and bleed valves in the steam line.
If Boiler #1 had a manhole, it too would need a block and bleed system.
Steam Line Stop Valves and Drains (ASME BPVC I): Required steam shut-off valves must be equipped with a position indicator.
Feedwater Piping (ASME B31.1): Each feedwater line to a boiler is required to have a check valve and a stop valve.
When multiple boilers are fed from a common source, a globe or regulating valve is required in the branch to each boiler.
Blowoff Piping (ASME B31.1): Boilers with allowable working pressures over 100 psig (690 kPag) require two slow-opening blowoff valves.
Traction and portable boilers, as well as forced circulation and electric steam boilers with a normal water content of 380 L (100 US gallons) or less, require only one blowoff valve.
Miscellaneous Piping (ASME B31.1): Various fittings attached to a low-pressure steam boiler include: a steam outlet stop valve, feedwater inlet stop and check valves, blowoff valves, vent valve, and water level controls.
Steam Outlet and Stop Valve (ASME BPVC IV): The steam produced in the boiler leaves through the steam outlet, and flows through the main header to the branch lines.
Gate valves and globe valves are commonly used on the steam outlet of a boiler.
Stop valves are used in the supply and return pipe connections of single and multiple boilers.

Studying That Suits You

Use AI to generate personalized quizzes and flashcards to suit your learning preferences.