18 Questions
What type of material is generally used for manufacturing boiler components?
Carbon and alloyed steels
When are carbon steels typically used in boiler components?
When the operating temperature is below 250℃
Why is it important to select appropriate materials for boiler components exposed to high temperatures and pressures?
To ensure safety and prevent failures
What is the primary function of feed water control in a boiler system?
To maintain the water level in the boiler
Why are internal circumferential corrugations important in boiler components?
To improve structural integrity
What is the purpose of furnace corrugations in a boiler system?
To improve heat transfer
What is the purpose of an exhaust gas economizer on a ship?
Reduce running cost and improve efficiency
Why are flat surfaces avoided in the design of pressure vessels?
To reduce the need for internal stays
What happens when a force is applied to a curved plate in a pressure vessel?
Internal forces are set up to withstand the force
Why are pressure vessels often given hemispherical ends?
To avoid the need for internal stays
What is the primary function of internal circumferential corrugations?
To reduce stress concentration
How do furnace corrugations impact stress concentration in a pressure vessel?
They increase stress concentration
What is the primary aim of internal circumferential corrugations to furnace tubes?
To reduce stress concentration on sharp edges
Why are end plates of spherical types preferred over flat end plates?
To reduce stress concentration on sharp edges
What is the function of feed water control in a boiler?
To regulate the water level based on steam demand
How do corrugations in a furnace tube affect heat absorption?
They allow a degree of flexibility to allow for expansion and contraction
What happens to water level in the gauge glass when a boiler is operating?
It reads higher than when the boiler is shut down
How does a level control system react to a situation of 'swell' in the boiler drum?
It opens the feed control valve to increase water level
Study Notes
Boiler Components and Design
- Carbon steels are typically used in boiler components when the operating temperature is below 450°C.
Material Selection for Boiler Components
- It is crucial to select appropriate materials for boiler components exposed to high temperatures and pressures to ensure durability and safety.
Feed Water Control in Boiler Systems
- The primary function of feed water control is to maintain a constant water level in the boiler drum.
Importance of Corrugations in Boiler Components
- Internal circumferential corrugations are important in boiler components as they increase the strength and durability of tubes.
- The primary function of internal circumferential corrugations is to increase the strength and durability of tubes.
Furnace Corrugations in Boiler Systems
- Furnace corrugations in a boiler system help to increase heat absorption by providing a larger surface area.
- Furnace corrugations reduce stress concentration in pressure vessels.
Exhaust Gas Economizer
- The purpose of an exhaust gas economizer on a ship is to recover heat from exhaust gases and use it to pre-heat feedwater.
Pressure Vessel Design
- Flat surfaces are avoided in the design of pressure vessels as they are more prone to deformation under pressure.
- When a force is applied to a curved plate in a pressure vessel, it distributes the force more evenly, reducing the risk of deformation.
- Pressure vessels are often given hemispherical ends to reduce stress concentration and increase strength.
- End plates of spherical types are preferred over flat end plates as they are stronger and more durable.
Boiler Operation and Level Control
- When a boiler is operating, the water level in the gauge glass fluctuates.
- A level control system reacts to a situation of 'swell' in the boiler drum by reducing the flow of feedwater.
Learn about the reasons why shells of cylindrical forms are preferred over other types and why end plates of spherical types are favored over flat end plates. Explore the stress concentration, surface area advantages, heat absorption benefits, and flexibility provided by these designs.
Make Your Own Quizzes and Flashcards
Convert your notes into interactive study material.
Get started for free
