Introduction
Start with the role of steam in industry, the steam and condensate loop, steam generation and the reasons steam remains an effective energy carrier.
Learn about steam
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.
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Steam engineering principles & heat transfer
Learn steam properties, heat transfer, steam consumption, engineering units, efficiency calculations and practical thermal system principles.
The boiler house
Learn boiler types, feedwater treatment, level control, blowdown, deaeration, testing, steam accumulators and boiler house efficiency principles.
Flowmetering
Learn steam flowmetering principles, meter types, installation requirements, density compensation and methods for accurate energy measurement.
Basic control theory
Learn process control fundamentals, control loops, proportional, integral and derivative action, stability, tuning and common control terminology.
Control hardware: Electric/pneumatic actuation
Learn how electric and pneumatic actuators, positioners, converters and control hardware operate in steam and industrial process control systems.
Control hardware: self-acting actuation
Learn how self-acting pressure and temperature controls use process energy to regulate steam systems without external electricity or compressed air.
Control applications
Explore practical steam control applications, valve sizing, heat exchanger control, pressure regulation and methods for stable process performance.
Safety valves
Learn safety valve principles, terminology, sizing, selection, installation and maintenance for protecting steam and process systems from overpressure.
Steam distribution
Learn steam main design, pipe sizing, drainage, separators, air venting, waterhammer prevention and best practices for reliable steam distribution.
Steam traps and steam trapping
Learn steam trap operating principles, trap types, selection, sizing, installation, testing and maintenance for effective condensate removal.
Pipeline ancillaries
Learn how separators, strainers, air vents, check valves, sight glasses and other pipeline ancillaries support reliable steam system operation.
Condensate removal
Learn condensate drainage principles, stall conditions, steam locking, pump-traps and equipment arrangements for reliable condensate removal.
Condensate recovery
Learn how condensate recovery reduces water, energy and chemical use through flash steam recovery, return lines, pumps and receiver systems.
Desuperheating
Learn desuperheating principles, spray-water control, equipment selection, installation and operating factors for accurate steam temperature control.
Further reading
Take A Closer LookThermal Exchange
Here, you will find much more about the concepts, strategies, and solutions surrounding steam systems and thermal engineering.
Complete Tutorial Directory
Click to expand each module and explore comprehensive tutorials and technical guides.
The steam and condensate loop
The steam and condensate loop explained How steam is generated, and why factors like feedwater, level control, and blowdown matter. Discover how steam gets to where it is needed, and why steam quality is important.
Steam and the organisation
Depending upon your role in your organisation, how steam is relevant to you will vary. From CEOs and managers to technicians and engineers, here we answer common questions about steam systems.
Steam - the energy fluid
Here we look at the many benefits that come from using steam as an energy source. Efficient, economic, flexible, and manageable, steam is widely used by many different industries.
Steam Consumption of Pipes and Air Heaters
Here we investigate how the pipes that carry steam affect the system's efficiency. The difference between warm-up and running loads are considered, and the calculations needed to measure heat loss. We also look at air heating equipment and how to assess these too.
Thermal Rating
Why your equipment's thermal rating cannot necessarily be taken as read, and the factors you will need to consider when interpreting it.
Steam Consumption of Heat Exchangers
This section focuses on shell and tube heat exchangers and plate heat exchangers. How they are used, their design and steam consumption calculations for them are all discussed. Finally, we look at other shell and tube steam heaters.
Heating Vats and Tanks by Steam Injections
The most common method of heating boiler feed tanks, heat is transferred by direct contact between steam and the liquid. The amount of steam needed, and the factors that might affect the heat transfer rate are dealt with here.
Engineering Units
A detailed look at the globally-agreed units used in steam system engineering. Many you will be familiar with, thanks to their widespread use, whilst we also examine those with specific relevance to steam.
Measurement of Steam Consumption
The three main ways of calculating your steam consumption are considered; a flowmeter, condensate pump, and condensate collection.
Heating with Coils and Jackets
A comprehensive look at submerged steam coils and steam jackets, the two most common ways of indirectly heating liquids in a vessel. The calculations needed, design, and controls are all covered.
Methods of Estimating Steam Consumption
Crucial to an efficient system, we look at the options for estimating your steam needs, both in flow and non-flow applications.
What is Steam?
Here we delve into the physics that lies behind steam. Understand the triple point, saturated steam tables, steam dryness, and what is flash steam.
Steam Consumption of Plant Items
Steam has many other uses. In this module we look at heater batteries, heating calorifiers, hot water storage calorifiers, drying cylinders, presses, and tracer lines. For each, we look at how steam consumption may be estimated.
Heat Transfer
A detailed look at how heat is transferred, the thermal conductivity of different materials, barriers to heat transfer, and the various equations needed to measure the efficiency of heat transfer.
Entropy - a basic understanding
A practical approach to understanding what entropy is, how it can be measured, and why entropy is so important to steam engineering.
Energy Consumption of Tanks and Vats
Widely used to contain liquids, tanks and vats are either open or closed. Here we look at how you can calculate the amount of energy needed for various situations.
Superheated Steam
Explore why superheated steam is used, the two theories used to measure its efficiency, the superheated steam table, and its pros and cons.
Entropy - its practical use
Find out how Temperature-Entropy and Enthalpy-Entropy charts can help you, how kinetic energy works in steam, and why understanding control valves is so important.
Steam Quality
Learn about the properties that ensure steam works effectively, why noncondensable gasses matter, and what is a water hammer (and why they should be avoided).
Installation of Level Controls
How to accurately gauge the water level in boilers, plus the details that will determine which method will be best for your system.
Testing Requirements in the Boiler House
A summary of how boiler testing is regularly carried out, with specific reference to the UK's regulations.
Water Levels in Steam Boilers
Crucial to their safe and efficient running, boiler water levels must be monitored and adjusted if necessary. We look at why this is important, and the effect of different loads on levels.
Pressurised Deaerators
A comprehensive look at how these remove unwanted gases from steam system water, and the principles and practices of their use.
Water for the Boiler
Options for treating water before its use in steam boilers, why carryover should be avoided, and the importance of water quality to different types of boilers are dealt with.
Boiler Ratings
The three commonly used methods for measuring boiler outputs, and the equations you will need to calculate them.
Steam Accumulators
Everything you need to know about steam accumulators, from assessing requirements, sizing, design, and operation, to controls, fittings, and injectors. Comprehensive calculations are also included.
Steam Headers and Off Takes
Various alternatives to boiler layouts, their smooth operation, the importance of warm-up, and making sure steam is distributed properly.
Water Level Alarms
Too much, or too little water in your boiler is something that must be avoided. This section looks at your options for warning of either situation.
Bottom Blowdown
The term used to describe the process of removing suspended solids from a boiler. We look at how this is done, the options for blowdown, and regulations controlling its operation.
Controlling TDS in the Boiler Water
See how to measure TDS, maintain the correct level, and how automatic TDS control can lead to cost and efficiency savings.
Miscellaneous Boiler Types Economisers and Superheaters
Used when steam isn't required all the time, and why economisers and superheaters are used.
Shell Boilers
A survey of various types of shell boilers, both wet and dry back. The development of the Lancashire boiler, the arrival of the packaged boiler, through to the reverse flame, or thimble boiler. We also look at the pressure and output limitations of shell boilers.
Boiler Efficiency and Combustion
How the efficiency of boilers is worked out, and a survey of the different options for burners, their controls, and impact on overall effectiveness.
Methods of Detecting Water Level in Steam Boilers
Learn how level controls, low and high water alarms work, and the differences between conductivity and capacitance probes. Float controls and differential pressure cells are also reviewed.
Water Treatment Storage and Blowdown for Steam Boilers
An examination of the many aspects of water quality and how they might affect steam boilers.
Automatic Level Control Systems
Here we take a close look at how boiler water levels may be automatically detected, and where problems might occur.
Heat Recovery from Boiler Blowdown TDS Control Only
Find out how much energy can be saved, and captured, when blowdown is used to control TDS. Both flash steam and heat exchangers are looked at.
Introduction
Factors to consider when choosing boilers, from local regulations, fuel options, and the various pros and cons associated with them.
The Feedtank and Feedwater Conditioning
Considerations and calculations needed to optimise your boiler feedtanks, pumps, and piping. We also examine deaerators and other important elements to think about when designing an efficient system.
Boiler Fittings and Mountings
To keep your boiler operating safely and efficiently a range of other valves, controls, and accessories are needed. Here we explain the importance of each.
Water Tube Boilers
How water-tube boilers work, variations using the same principles (drum boilers and the Stirling boiler), and their advantages and disadvantages. We also look at combined heat and power plants (CHP), and combined cycle plants.
Principles of Flowmetering
An in-depth look at the science behind flowmetering, the equations used to maximise its effectiveness, and how ultrasound is used to measure flowrate.
Types of Steam Flowmeter
Discover the seven types of flowmeter used to measure steam and condensate. We consider how each works, their advantages and disadvantages, and where they are often found.
Instrumentation
Here we break down how flowmeters interpret data, why pressure variations must be considered, and understand how dryness fractions and superheat can impact accuracy.
Installation
With over a third of flowmetering problems stemming from poor installation, it's important to get the design and installation right. This section will give you a checklist for selecting the right flowmeters, and a comprehensive set of recommendations for their installation.
Fluids and Flow
An examination of the fundamental principles behind measuring the flow of steam, including density, viscosity, velocity, the Reynolds number, and flow regimes.
Installation and commissioning of controls
A detailed look at the elements involved in the installation and commissioning of controls, including how the Ziegler-Nicholls method can be used for setting controllers.
Basic Control Theory
Put simply, the two basic control options are either on/off or continuous control. This module looks in detail at the implications of each, paying close attention to the three elements of continuous control: proportional, integral, and derivative.
Choice and Selection of Controls
How to Choose Which Controls to Use? An overview of your options (self-activating, pneumatic, electric, electro-pneumatic), a look at valves and actuators, and choices of controllers. Guided by consideration of safety, stability, and accuracy.
Control loops and dynamics
What is a control loop, what are the differences between control loop options (open, closed, single, multi, cascade), what happens in each control loop, and various process reactions are all answered in this topic.
Computers in Controls
Looking at the evolution of IT helping improve control, up to the introduction of fieldbus technology in streamlining operations.
An introduction to controls
Here we investigate why automatic controls are more reliable than manual options, and look at how controls deal with processes that use steam, water, compressed air, and hot oils.
Control Valves
Get to know the different types of control valves used in steam and fluid systems. The differences between linear and rotary valves, with two or three-ports, is simply explained using animated diagrams.
Control Valve Sizing For Steam Systems
Your complete guide to unravelling the complicated subject of steam control valve sizing. Find out how to use formulae and steam tables to make sure you have the right sized valve, the issues you may need to consider (velocity, noise, erosion, drying, and superheated steam), together with a checklist of the 20 major factors to assess your system.
Control Valve Characteristics
Different types of valve plug have different flow characteristics. This section gives you a thorough understanding of the three main types (fast opening, linear, and equal percentage), and using detailed case studies, how the flowrates are calculated.
Control Valve Sizing For Water Systems
Here you will find out how to correctly size valves using either equations or charts. The difference between imperial and metric measurements is explained, how two- and three-port valves differ in how they operate, and why valve authority, cavitation, and flashing need to be considered.
Controllers and Sensors
What they are, when to use them, and the many variations available. We also look at advanced control systems using the HART protocol and fieldbus standards.
Control Valve Capacity
Valves work by altering either flowrate or differential pressure. Gain an understanding of the flow coefficient, and how it is used to compare valve performance.
Control Valve Actuators and Positioners
This section looks at how actuators enable valves to work, the differences between pneumatic and electric versions, how reverse acting and direct acting actuators work, and why positioners are sometimes also essential for safe and accurate control.
Level Control Applications
An overview of the different types of level control systems used, with particular focus on float and solid probe types, most commonly used in the steam and condensate loop. There is a focus on conductivity and capacitance level controls.
Control Installations
How and where your control system is installed with have a marked effect on its accuracy and lifetime. Here we look at the factors to consider to ensure it works at its best for as long as possible.
Temperature Control Applications
When it is the temperature that must be controlled, there are five main methods for doing so. Here we look at their advantages and disadvantages, and where they are usually used. We also survey some of the other options for controlling steam temperature.
Pressure Control Applications
In this comprehensive review of the methods used to control steam pressure, we look at the advantages and disadvantages of each, the situations where they are usually employed, and important points to note. We also touch upon alternative methods sometimes used.
Alternative Plant Protection Devices and Terminology
They might be the most effective, but safety valves are not the only way you can deal with excess pressure. This section looks at the alternatives and gives a full glossary of terms related to this topic.
Types of Safety Valve
Discover in detail the many variations of safety valves, how they operate (including equations illustrating the force needed to do so), and diagrams of each type of valve.
Safety Valve Installation
For it to work correctly, it's vital you know all the factors to make the right decision. Everything you need to know is covered here.
Safety Valve Sizing
A detailed look at how to size valves according to various standards, with diagrams and equations for each case. We also look at more complicated solutions like two-phase flow and superheat.
Safety Valve Selection
Including the criteria you will need to consider, how safety valves are properly installed, and where, and the difference between MAWP and MAAP.
Safety Valves
Safety valves are essential devices used to protect from steam overpressure. Here we look at how this might happen, the range of types available, how they work, and the regulatory frameworks for them.
Pipe Expansion and Support
Because they are carrying hot fluids or steam, allowance must be made for expansion. Here we cover the various methods of making sure your pipes are properly installed.
Steam Mains and Drainage
We look at the overall layout, condensate drain points, using branch lines, steam separators and strainers, how to calculate your running load, and what to look out for to avoid waterhammer.
Pipes and Pipe Sizing
Covering the international standards, schedule numbers, piping materials, and detailed information on the equations, charts, and tables needed to pick the correct piping. Includes comprehensive appendices.
Air Venting Heat Losses and a Summary of Various Pipe Related Standards
How to effectively remove air and noncondensable gases from a steam system, and how to calculate, and reduce, heat losses from pipework. Includes relevant international standards covering the subject.
Introduction to Steam Distribution
Here we examine what is the steam and condensate loop, the working pressure of a system, and see why pressure-reducing valves are used.
Mechanical Steam Traps
These use the different densities between steam and water (condensate) to operate. There are two main types: the ball float trap, and the inverted bucket trap. Able to remove large volumes of condensate, mechanical steam traps are used in a wide range of process applications. Discover how each works, and their advantages and disadvantages.
Introduction - Why Steam Traps?
The main job of a steam trap is to remove condensate, air, and any noncondensable gases from a steam system whilst minimising the escape of live steam. Here we look at why this is necessary, how they do this, their basic operation, and the standards applied to steam traps.
Selecting Steam Traps - Canteen Equipment Oil Transfer Storage Hospital Equipment
Giving tables and advice on picking the right options for these uses, from boiling pans to bulk storage tanks, to autoclaves and sterilisers.
Testing and Maintenance of Steam Traps
Examining routine maintenance, replacement of internal parts, and potentially replacing steam traps. However, accurately identifying issues with steam traps requires expert knowledge, and we look at manual, remote, and automatic monitoring to determine if there actually is a problem.
Selecting Steam Traps - Space Heating Equipment
Best and acceptable alternative choices of steam traps for calorifiers, heater batteries, radiant panels and strips, radiators and convection cabinets, unit heaters and air batteries, and overhead pipe coils.
Thermostatic Steam Traps
These work by responding to the surrounding steam temperature. There are three main types: liquid expansion traps, bimetallic traps, and balanced pressure traps. We look at each, with animated diagrams showing how they work, and the pros and cons of each.
Air Venting Applications
Examining many of the cases where air venting will be needed, including the steam mains, jacketed pans, and rotating cylinders. We also consider the use of steam trap bypasses, and how thermostatic steam traps can also be used as air vents.
Thermodynamic Steam Traps
It is a very robust form of trap, with only one moving part, that operates using the dynamic effect of flash steam as it passes through the trap. We examine the traditional thermodynamic steam trap, the impulse type, the labyrinth type, and finally fixed orifice traps. How they're made, their uses and pros and cons are discussed.
Considerations for Selecting Steam Traps
Other things to take into account when choosing steam traps: waterhammer, dirt, strainers, steam locking, group trapping, diffusers, and special needs, like vacuum drainage and trapping for temperature-controlled processes.
Selecting Steam Traps - Process Equipment
Advice on the ideal steam traps for fixed and tilting boiling pans, retorts, industrial autoclaves, industrial digesters, hot tables, brewing coppers, evaporators, and vulcanisers.
Selecting Steam Traps - Industrial Dryers
Advice on choosing traps for hot air dryers, drying coils, multi-bank pipe dryers, drying cylinders, and multi-cylinder dryers.
Energy Losses in Steam Traps
Often steam traps are blamed for energy losses simply to gain a new sale for an alternative. This section honestly looks at the three types of main steam trap and demonstrates just how little energy steam traps use. trap types.
Air Venting Theory
Because air is an insulator, it works against the efficient heat transfer of a steam system. This section looks at how to detect air in the system, and how to remove it effectively.
Selecting Steam Traps - Steam Mains Tanks and Vats Pressure Reducing Valves
Covering aspects of the steam mains operations, including horizontal runs, drain pocket dimensions, separators, steam header drainage, and terminal ends. We also look at process vats and small coil-heated tanks.
Selecting Steam Traps - Laundries and Presses
Looking at the right steam traps for garment presses, ironers and calenders, tumble dryers, dry cleaning machines, and various types of presses, including tyre presses.
Strainers
Usually classified as either Y-type or basket type, strainers prevent damage from debris in flowing liquids or gases, so reducing plant downtime and unplanned maintenance costs. Here we take a detailed look at the options, and how to select the right size, depending upon your processes.
Isolation Valves - Rotary Movement
Sometimes known as quarter-turn valves, we delve into ball valves and their various options, and butterfly valves. This section also gives details on selecting isolation valves, including their sizing, with comprehensive charts and the equations for getting to the right choice.
Isolation Valves - Linear Movement
Used to stop the flow of fluid into an area of the system, we look at the different types of gate valves, globe valves, piston valves, and diaphragm valves. We also look at options for valve stems, and how to seal them.
Gauges Sight Glasses Vacuum Breakers
Though relatively small in size, these play a big part in the smooth running of energy-efficient steam systems. We examine what each does, and how they work.
Separators
Important tools in reducing 'wet steam', separators come in various forms. We look at baffle, cyclonic, and coalescence separators, detailing which option to choose, and how to calculate the dryness fraction.
Check Valves
Also known as non-return valves, a check valve will only allow flow in one direction. The main types used for steam are lift, swing, wafer, and disc check valves. Ball and diaphragm check valves are usually used in fluid applications. Formulae for calculating pressure drops are also given.
Practical Methods of Preventing Stall
Methods of dealing with condensate drainage problems include gravity drainage, adding an automatic pump trap device, and controlling the pressure in the steam space.
Oversized Heat Exchangers
Often heat exchangers are bigger than needed for the job they need to do. This section looks at the implications of this, the effects on issues like selecting the right steam traps for them, and details the equations needed to deal correctly with this common problem.
The Stall Chart - Constant Flow Secondary - Constant Inlet Temperature - Varying Outlet Temperature
Using this simple method, stall can be worked out for an situation with a constant secondary flowrate with a varying inlet temperature.
The Stall Chart - Constant Flow Secondary - Varying Inlet Temperature - Constant Outlet Temperature
In cases where constant flow is secondary, there is varying inlet temperature, and constant outlet temperature.
Example Selecting The Trap
Step-by-step illustration for calculating stall and how to select the right condensate removal solution for a heat exchange application.
Heat Exchangers And Stall
Investigating how to remove condensate from heat exchangers fitted with a temperature control valve on the steam line, and a steam trapping device on the condensate line from the heat exchanger.
The Heat Load Heat Exchanger and Steam Load Relationship
The equations needed to determine the design loads and steam pressure and flowrate requirements for heat exchange applications.
The Stall Chart - Varying Flow Secondary - Constant Inlet Temperature - Constant Outlet Temperature
Sometimes constant secondary flow is not required, such as providing hot water to batch processes like tank or vats. This example shows how to use the chart in these cases.
Introduction to Condensate Recovery
Why condensate recovery and return are useful, saving energy costs, reducing environmental discharges, and keeping water treatment costs down. Covers calculations for potential savings.
Layout of Condensate Return Lines
A fully-illustrated, detailed look at the design and layout of condensate return pipework. This includes the effect of trap types used, how different pressures impact the system, and the discharge of condensate into flooded mains.
Pumping Condensate from Vented Receivers
This comprehensive introduction covers pumping terminology, the operation, application and various benefits of electric centrifugal and mechanical condensate pumps. There are sizing examples for both pumps and pump discharge lines.
Sizing Condensate Return Lines
How to size condensate lines to and from steam traps, with examples and formulae needed using the condensate pipe sizing chart.
Lifting Condensate and Contaminated Condensate
Here we look at moving condensate to a higher level return line, and ways to cope with contaminated condensate.
Flash Steam
What is flash steam, how much is available, how it can be recovered, controlling flash steam, and its applications.
Basic Desuperheating Theory
The difference between superheated and desuperheated steam is detailed, where both types of steam are typically used, and calculations for desuperheating.
Basic Desuperheater Types
First we cover the issues to think about when selecting a desuperheater, such as turndown ratio. Then we survey the types of desuperheater available, including indirect contact, direct contact, water spray, and axial injection desuperheaters. Consideration of the advantages and disadvantages of each is offered.
Other Types of Desuperheater
A range of other desuperheaters are commonly used. Here we look at venturi type, steam atomising, variable orifice, combined pressure control valve and desuperheater, and compare the options alongside one another.
Typical Installations
There are a range of factors that must be considered. This section looks at key issues, including the properties of the cooling water itself, the installation of the desuperheater, pressure control, and sensor positioning.