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Steam Engineering Tutorials
These tutorials explain the principles of steam engineering and heat transfer. They also provide a comprehensive engineering best practice guide covering all aspects of steam and condensate systems; from the boiler house and steam distribution system up to the point of use; through the condensate recovery system and returning to the boiler. Virtually all major applications and products are discussed.
- Steam Engineering Principles and Heat Transfer
- The Boiler House
- Basic Control Theory
- Control Hardware: Electric/Pneumatic Actuation
- Control Hardware: Self-acting Actuation
- Control Applications
The introduction of steam as a useful and powerful purveyor of energy. It discusses the versatile uses and benefits of this ubiquitous vapour; and the ways in which it is produced and distributed to achieve maximum performance and economy for the end user.
Properties of various types of steam are considered, along with basic heat transfer principles and how to calculate consumption rates for process applications. Entropy is tackled in simple terms, removing unnecessary fears often associated with the subject.
- Engineering Units
- What is Steam?
- Superheated Steam
- Steam Quality
- Heat Transfer
- Methods of Estimating Steam Consumption
- Measurement of Steam Consumption
- Thermal Rating
- Energy Consumption of Tanks and Vats
- Heating with Coils and Jackets
- Heating Vats and Tanks by Steam Injection
- Steam Consumption of Pipes and Air Heaters
- Steam Consumption of Heat Exchangers
- Steam Consumption of Plant Items
- Entropy - A Basic Understanding
- Entropy - Its Practical Use
Various types of boilers and fuels are discussed, alongside the best ways in which to get the best out of this important part of the steam plant. All necessary associated boiler equipment is considered, including basic deaerator and accumulator theory.
- Shell Boilers
- Water-tube Boilers
- Miscellaneous Boiler Types, Economisers and Superheaters
- Boiler Ratings
- Boiler Efficiency and Combustion
- Boiler Fittings and Mountings
- Steam Headers and Off-takes
- Water Treatment, Storage and Blowdown for Steam Boilers
- Water for the Boiler
- The Feedtank and Feedwater Conditioning
- Controlling TDS in the Boiler Water
- Heat Recovery from Boiler Blowdown (TDS control only)
- Bottom Blowdown
- Water Levels in Steam Boilers
- Methods of Detecting Water Level in Steam Boilers
- Automatic Level Control Systems
- Water Level Alarms
- Installation of Level Controls
- Testing Requirements in the Boiler House
- Pressurised Deaerators
- Steam Accumulators
Fluid characteristics and flow theory (including Bernoulli's theorem and Reynolds' numbers) are introduced and developed to provide basic metering theory and techniques. Different meter types, instrumentation and installation practice are also discussed.
Control theory is discussed from fundamental proportional action to PID control. The dynamic of the simple control loop is discussed, alongside practical issues of choosing the best system for the application, and installation and commissioning issues.
Control valve capacities and characteristics are investigated, along with theory and practical advice on how to size them for water and steam systems. Actuators, positioners, and controllers are introduced plus their overall effect on the control loop.
Basic self-acting control theory is discussed, alongside the different types of direct-acting and pilot-operated valves, controllers, and applications for the proper selection of temperature and pressure control of steam and water systems.
A brief summary of, and advice on, temperature, pressure, flow and level control methods to suit various types of steam applications, with consideration to surplussing control, differential pressure control, and cascade control and installation thereof.
Arguably, the most important subject in the generation, distribution and use of steam. Why are safety valves required? What different types are available and how are they selected, sized and installed? Other protection devices are also shown in some detail.
Efficient distribution gets clean dry steam to apparatus at the right pressure. Pipe sizing, essential drainage techniques, pipe support and expansion, air venting, and heat transfer calculations are included to help the system designer and practitioner.
How steam traps work and why steam traps are necessary. All is explained in this block, along with the different types, where they are used, and how they are selected. Air venting theory and applications are touched upon, along with steam trap maintenance.
- Introduction - Why Steam Traps?
- Thermostatic Steam Traps
- Mechanical Steam Traps
- Thermodynamic Steam Traps
- Considerations for Selecting Steam Traps
- Selecting Steam Traps - Canteen Equipment; Oil Transfer/Storage; Hospital Equipment
- Selecting Steam Traps - Industrial Dryers
- Selecting Steam Traps - Laundries, Presses
- Selecting Steam Traps - Process Equipment
- Selecting Steam Traps - Space Heating Equipment
- Selecting Steam Traps - Steam Mains; Tanks and Vats; Pressure Reducing Valves
- Air Venting Theory
- Air Venting Applications
- Testing and Maintenance of Steam Traps
- Energy Losses in Steam Traps
These are often neglected to save costs; but strainers, stop valves, check valves, separators, gauge glasses and vacuum breakers all have their part to play in an efficient steam system. This block explains why, and explores the different types available.
Proper condensate removal is essential to heat exchanger efficiency and long service life. An explanation of how heat exchangers operate. It introduces the subject of stall, and why and how the best trapping device is selected to maximise system efficiency.
- Heat Exchangers and Stall
- The Heat Load, Heat Exchanger and Steam Load Relationship
- Oversized Heat Exchangers
- Example: Selecting the Trap
- The Stall Chart - Constant Flow Secondary - Varying Inlet Temperature - Constant Outlet Temperature
- The Stall Chart - Varying Flow Secondary - Constant Inlet Temperature - Constant Outlet Temperature
- The Stall Chart - Constant Flow Secondary - Constant Inlet Temperature - Varying Outlet Temperature
- Practical Methods of Preventing Stall
Relaying condensate back to the boiler house reduces costs. Pipe sizing and layout is discussed for drain lines, discharge lines, and pumped lines. The effects of lift and backpressure are explained; and how to reduce overall costs by utilising flash steam.
Why is it necessary to desuperheat steam? What types of desuperheater exist, where are they used, and how are they installed? Basic types and more sophisticated types of desuperheater and their applications are discussed in some detail.
A list of all the equations used in the complete set of Steam Engineering Tutorials relating to the subject of how to get the best out of the steam and condensate loop.