DC 1st Class Boiler Exam Questions and Answers 100% Correct
8 views 0 purchase
Course
DC 1st Class Boiler
Institution
DC 1st Class Boiler
DC 1st Class Boiler Exam Questions and Answers 100% CorrectDC 1st Class Boiler Exam Questions and Answers 100% CorrectDC 1st Class Boiler Exam Questions and Answers 100% CorrectDC 1st Class Boiler Exam Questions and Answers 100% Correct
Moving blading in which space between blades is the same size...
DC 1st Class Boiler Exam
Questions and Answers 100%
Correct
Moving blading in which space between blades is the same size at the blading inlet,
and the blading outlet. - ANSWER-Impulse Blading
To blowdown a boiler equipped with a quick opening and slow opening valve on the
bottom blowdown line, the_________. - ANSWER-quick opening valve is opened first
and closed last.
Hardness of water is the measurement in ppm of ________ and ________ in the water.
- ANSWER-calcium and magnesium
A pump delivers 175 gallons per minute against a pressure of 55 psi; the suction
pressure is 15 psi. If a pump is 80% efficient, what is the horsepower needed? -
ANSWER-HP=5.1 HP= (Head in Feet) x (Weight in Lbs.)/ 33,000 x Efficiency
a duplex double-acting reciprocating feed water pump has____ - ANSWER-two steam
Pistons 2 to 2 2/2 times larger in area than the water piston
Name a technique to control the nitrous oxide emissions. - ANSWER-Selective
Catalytic Reduction
Spalling in a boiler occurs in the ____? - ANSWER-Combustion chamber
A technology in which solid waste is heated in an oxygen starved atmosphere to
break down the solids into a gas is called ______? - ANSWER-Pyrolysis
What is the primary purpose of using wet scrubbers? - ANSWER-To remove sulfur
dioxides
, The thermal efficiency of a boiler with a stack temperature of 750°F and and a
furnace temperature of 3200°F is_______? - ANSWER-75% ((3200-750)/3200) x 100
________is a water-purification process in which the water to be treated is
pressurized and applied against the surface of a semipermeable membrane. -
ANSWER-Reverse osmosis
The airflow switch at the burner fan housing______. - ANSWER-Ensures the primary
air fan is functioning
How many inches of steam space in a cylinder of an engine 12"x28" and the stroke
is 5/8 of its full travel? - ANSWER-1978. V=AxL V=3.14(6x6)x28x.625= 1978
What is the horsepower requirement of a pump that moves 2500 gpm of water
against a head of 475' if the pump is operating at 58% efficiency? - ANSWER-516.8
HP=Head x Weight/33000 x efficiency. (Head =475, Weight = 2500gpm x 8.33)
(475x 20825)/19140
A ______ is the condition that is being controlled - ANSWER-process variable
Although boiler tubes and boiler drums withstand the same pressure, the walls of
the boiler tubes are much thinner because ______. - ANSWER-The tubes are much
smaller in diameter
A lead sulfide cell detects_____. - ANSWER-Burner pilot and main flame
Which of the following indicates a malfunction in the DC heater? 1. The boiler
requires excessive amounts of oxygen absorbing chemicals.
2.Water and steam are entering the DC heater at the same temperature. - ANSWER-
Both 1 & 2
______ is the plasticity exhibited by a material under tension loading. - ANSWER-
Ductility
The benefits of buying summaries with Stuvia:
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
You can quickly pay through credit card or Stuvia-credit for the summaries. There is no membership needed.
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 NursingTutor1. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for $14.99. You're not tied to anything after your purchase.
