3A2: Power Engineering

e - Answer To accommodate thermal expansion on pipe lines carrying hot fluids such as steam, expansion bends are occasionally used. The use of expansion bends may be preferred: a. For low pressure service b. To reduce heat loss c. Because it reduces pipe friction losses d. Because it takes up less space than other types of expansion means e. For high pressure service. b - Answer The three methods of welded pipe manufacture are: 1. Piercing and rolling 2. Electric fus...

1. Bimetal thermometers consist of two thin metal strips bonded together. The metal strips must have: a. A small difference in coefficient of expansion b. A large difference in coefficient of expansion c. No difference in coefficient of expansion d. Equal coefficients of linear expansion e. Equal coefficients of volumetric expansion. - Answer b 2. The coefficient of expansion of aluminum is _____ that of copper. a. Equal to b. Twice c. One half d. Less than e. More th...

what does MCC stand for - Answer motor control center what is the name of the electrical device that is usually open but may be closed to connect one side of a bus to the other? - Answer tie breaker in reference to a circuit diagram of a high voltage power supply, what does ATS stand for? - Answer automatic transfer switch in a high voltage power supply, what is a duel fed system - Answer where two independent power lines are used to supply the same load in a dual...

A fluidized bed of limestone will significantly reduce _____ emissions by the combination of sulphur dioxide with the limestone. Select one: A. Sulphur dioxide B. Nitrous oxide C. Carbon dioxide D. Oxygen E. Nitrogen - Answer A The advantages of natural gas as a boiler fuel include: 1. Clean burning, no ash is produced 2. Cost of the fuel 3. Easily mixed with air 4. Requires large diameter transmission lines 5. Does not require extensive handling equipment Select one: A. 1, ...

In falling shot cleaning, iron shot or pellets, _________ mm in diameter fall by gravity: Select one: a. 6 b. 9 c. 3 d. 12 - Answer a With this system, not electrical power is required to feed make-up water to the boiler: Select one: a. gravity return system b. pump return system c. low flow return system d. high side return system - Answer a Combustion air provide din addition to primary and secondary air used to completer the combustion processes in some burner de...

On/off control systems are used where the most basic control is required. The requirements for successful on/off control are: - Answer 1) Economics of the process do not require precise control 2) Precise set point is unnecessary 3) Variables such as Heat and Level are generally slow and work best with on/off control 4) Manipulated variable energy or volume flowing into the process is relatively small compared to the capacity of the process 5) The operation of the FCE produces small c...

The separately excited generator has a _____ load characteristic: a. Parallel. b. Rising. c. Level. d. Falling. e. Series - Answer c. Level. Armature reaction _____ the main field of a generator. a. Restores. b. Reverses. c. Increases. d. Decreases. e. Distorts. - Answer e. Distorts. The armature core in a DC machine is made of: a. Stainless steel laminations. b. Copper laminations. c. Copper. d. Soft iron laminations. e. Hard steel laminations...

Process parameters such as temperature, pressure, and flow require continuous measurements in real time. If review of the measurements is desired, provision must be made to capture the parameters with respect to time. a. True b. False - Answer a. True The controller uses an operational amplifier to perform a mathematical summation, in order to compare the input signal (process variable) with a setpoint that is established by operations personnel. If the process is not at the set va...