3B2 - Ultimate ABSA Study Guide C1-15 Study Guide

3B2 - Ultimate ABSA Study Guide C1-15 Study Guide Questions with Complete Solutions 100% Verified Correct Answers Latest Updated 2024/2025

Turbine nozzles convert heat energy into:

• Potential energy.
• Enthalpy.
• Eddy-currents.
• Kinetic energy.
• Pressure. - Correct Answer D

Labyrinth seals are:

• Made of cast iron.
• A positive leak-proof seal arrangement.
• Design to have large clearances between the shaft and casing.
• Made of brass or stainless steel.
• Used on larger diameter turbine shafts.
• 1, 2.
• 2, 4, 5.
• 3, 4, 5.
• 4, 5.
• 1, 2, 3. - Correct Answer D

Flange warming on a steam turbine decreases:

• Creep.
• Start up time.
• Movement.
• Radiation losses.
• Noises. - Correct Answer B 1 / 4

In pressure compound steam turbines:

• The expansion of steam from boiler pressure to exhaust

pressure is carried out in a number of steps or stages.

• Each stage has a set of nozzles and a row of blades.
• All of the velocity available is developed in one set of nozzles.
• Rows of moving blades are separated by partitions or

diaphragms into which nozzles have been installed.

• 1,2,3.
• 2,3,4
• 1,3,4
• 2,4
• 2,3,4. - Correct Answer D

In a/an _____ turbine there is a difference in pressure across the _____ blades. Therefore the steam will tend to _____ around the periphery of the blades instead of passing through them.

• Impulse.
• Moving.
• Reaction.
• Drip.
• Stationary.
• Leak.
• 1,2,4.
• 3,5,6.
• 3,2,6.
• 1,5,4.
• 1,5,6. - Correct Answer C

The pressure at the outlet from the moving blades is the same as the pressure at the inlet to the moving blades in a/an turbine. 2 / 4

• Topping.
• Reaction.
• Back pressure.
• Impulse.
• Extraction. - Correct Answer D

When disc rotors are assembled, the discs are heated until they are easily slid along the shaft and then located in the correct position on the shaft and shaft key. A small clearance between the discs prevents:

• Noise.
• Slippage.
• Thermal stress in the shaft.
• Acceleration.
• Vibration. - Correct Answer C

In an impulse steam turbine nozzle the following events take place:

• Steam pressure decreases
• Enthalpy of the steam decreases
• Velocity of the steam increases
• Volume of the steam increases
• 1,2,4
• 1,3,4
• 2,3,4
• 1,2,3
• 1,2,3,4 - Correct Answer E

A turbine that expands the steam in two or more sets of nozzles in series, each set having velocity- compounded blades to receive the steam issuing from the nozzles is called a/an: 3 / 4

• Extraction turbine.
• Velocity compounded turbine.
• Pressure compounded turbine.
• Pressure-velocity compounded turbine.
• Mixed-pressure turbine. - Correct Answer D

In a back-pressure turbine the process steam pressure is:

• Kept constant and the generator output depends on the demand for process steam.
• Varied and the generator output remains constant.
• Kept constant and the generator output remains constant.
• Not important.
• Dependant on the generator output. - Correct Answer A

Extraction turbines are turbines where steam is extracted at one or more points at constant:

• Flow.
• Pressure.
• Load.
• Temperature.
• Efficiency. - Correct Answer B

_____ turbines are large turbines with parallel shafts with a generator on each shaft.

• Condensing.
• Tandem-compound.
• Extraction-bleeder.
• Condensing-bleeder.
• Cross-compound. - Correct Answer E

Steam turbine stationary nozzles create a:

• Decrease in steam pressure.
• / 4