100% satisfaction guarantee Immediately available after payment Both online and in PDF No strings attached
logo-home
Previously searched by you
Previously searched by you
logo
Power Engineering 4th Class - B3 Updated questions and answers $10.99
Add to cart
Quickly navigate to
Preview
  2.  
  3. Power Engineering
  4.  
  5. Power Engineering

Exam (elaborations)

Power Engineering 4th Class - B3 Updated questions and answers
 0 purchase
  • Course
  • Power Engineering
  • Institution
  • Power Engineering

Power Engineering 4th Class - B3 Updated questions and answers The type of firing rate control frequently used on small capacity packaged boilers is: a. a modulating control b. a high fuel pressure cut-off c. a constant pressure control d. an on/off control - ANS d A feedwater pipe, wh...

[Show more]

Preview 3 out of 18  pages

Document information

  • August 29, 2024
  • 18
  • 2024/2025
  • Exam (elaborations)
  • Questions & answers

Subjects

  • power engineering 4th class b3 updated questions

Written for

  • Power Engineering
  • Power Engineering

Seller

avatar-seller
JPNAOMISTUVIA

Reviews received

Content preview

Power Engineering 4th Class - B3 Updated
questions and answers
The type of firing rate control frequently used on small capacity packaged boilers is:

a. a modulating control
b. a high fuel pressure cut-off
c. a constant pressure control




A
d. an on/off control - ANS d




VI
A feedwater pipe, where connected to a power boiler, must have:

a. A quick and slow opening stop valve




TU
b. A stop valve only
c. A check valve between the stop valve and the boiler
d. A check valve, with a stop valve between the check valve and the boiler - ANS d
IS
An essential fitting between the boiler and the steam pressure gauge is a:

a. Siphon
OM

b. Gauge glass
c. Gate valve
d. Check valve - ANS a

A variable resistance modulating control:
NA


a. Works in conjunction with a modulating motor
b. Utilizes a mercury switch
c. Senses steam temperature
JP




d. Operates only in the vertical position - ANS a

If a boiler produces steam at a higher rate than the rate of steam consumption, and this
condition goes unchecked

a. soot will develop on the fireside
b. the boiler efficiency will drop
c. the boiler will overheat
d. the boiler will over-pressurize - ANS d

,A boiler feedwater isolation valve:

a. May be a globe valve, provided water enters below the disc
b. Should be located close to the feedwater pump
c. Must be a globe valve
d. Is used to isolate the deaerator - ANS a

A hot water boiler operating control (Aquastat) may be a pressure switch:




A
a. that is normally open
b. that responds to the expansion and contraction of boiler water




VI
c. operated by a filled system thermometer
d. that is sensitive to steam pressure - ANS c




TU
In steam boiler firing rate control systems, the measured variable is

a. fuel pressure
b. combustion air damper position
IS
c. the steam pressure
d. firing rate control valve position - ANS c
OM

Do not open the safety valve with the test lever:

a. If the valve is not vented to the roof
b. If there are more than two safety valves on the boiler
c. If the pressure is less than 75% working pressure
NA


d. If the valve is less than 2.5 cm inlet diameter - ANS c

Transparent gauge glasses are lined with mica to:

a. Provide a high temperature seal
JP




b. Increase the strength of the glass
c. Cool the glass
d. Protect the glass - ANS d

A boiler with a single safety valve has a maximum allowable working pressure of 1000
kPa. What is the maximum boiler pressure permissible when the safety valve is
blowing?

, a. 1100 kPa
b. 1030 kPa
c. 1000 kPa
d. 1060 kPa - ANS d

How many blow-off valves are required by most power boilers?

a. Two
b. Three
c. One




A
d. Zero - ANS a




VI
When a boiler steam outlet stop valve is required by code, the preferred style of valve
is:




TU
a. a ball valve
b. a non-rising stem gate valve
c. an outside screw and yoke, rising stem valve
d. a non-rising stem globe valve - ANS c
IS
The purpose of the tee fitting on the piping leading to a boiler steam pressure gauge is
to:
OM

a. Attach a test gauge
b. Blowoff condensate from the pigtail
c. Test a sample of steam for purity
d. Bypass the siphon tube - ANS a
NA


A packaged steam boiler modulating combustion control system will routinely:

a. Maintain drum level within a desired range
b. Maintain flue gas temperature at some set point
JP




c. Maintain boiler steam pressure within a desired range
d. Alter flue flow without changing the air flow - ANS c

Every steam boiler must have a safety valve that is:

a. Connected to the steam or water space of the boiler, without any intervening fitting.
b. Fitted in a vertical position, directly connected to the top of the boiler.
c. Fitted securely to a shut-off valve, which is directly connected to the top of the boiler.

The benefits of buying summaries with Stuvia:

Guaranteed quality through customer reviews

Guaranteed quality through customer reviews

Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.

Quick and easy check-out

Quick and easy check-out

You can quickly pay through credit card or Stuvia-credit for the summaries. There is no membership needed.

Focus on what matters

Focus on what matters

Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!

Frequently asked questions

What do I get when I buy this document?

You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.

Satisfaction guarantee: how does it work?

Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.

Who am I buying these notes from?

Stuvia is a marketplace, so you are not buying this document from us, but from seller JPNAOMISTUVIA. Stuvia facilitates payment to the seller.

Will I be stuck with a subscription?

No, you only buy these notes for $10.99. You're not tied to anything after your purchase.

Can Stuvia be trusted?

4.6 stars on Google & Trustpilot (+1000 reviews)

69252 documents were sold in the last 30 days

Founded in 2010, the go-to place to buy study notes for 15 years now

Start selling
$10.99
  • (0)
Add to cart
Added