Valves used in steam systems are not simply basic equipment designed to open and close the flow. Since steam is transported under high temperatures and pressures, valve selection directly affects system safety, energy efficiency, maintenance costs, and equipment service life.

However, not every valve performs the same function in steam piping systems. A ball valve used for quick opening and closing in a line does not serve the same purpose as a globe valve used in applications requiring flow control. Similarly, a butterfly valve, which can provide advantages in large-diameter lines, is not an alternative to a steam trap used to discharge condensate.

So, which valve should be used for which application in steam systems?

In this article, we will compare ball valves, globe valves, butterfly valves, and steam traps in terms of their functions, applications, and selection criteria.

Why Is Valve Selection Important in Steam Systems?

Temperature and pressure values in steam lines can be higher than in many liquid applications. Therefore, simply considering the connection diameter is not sufficient when selecting a valve.

The following factors should be evaluated together when determining the right product:

• Steam operating pressure,

• Operating temperature,

• Line diameter,

• Steam flow rate,

• Valve function,

• Body and sealing materials,

• Connection type,

• Flow control requirements.

For example, a valve selected solely based on DN size may not be suitable for the system's temperature or pressure conditions. Incorrect selection can result in leakage, energy loss, pressure drop, equipment damage, and unplanned maintenance.

İsimatik's existing content also emphasizes that parameters such as fluid type, pressure, temperature, and diameter should be evaluated together when selecting a valve.

Which Types of Valves Are Used in Steam Systems?

Different types of valves and equipment may be used at different points in steam piping systems.

The most commonly encountered equipment includes:

1. Ball valves

2. Globe valves

3. Butterfly valves

4. Steam traps

5. Check valves

6. Pressure-reducing regulators

7. Control valves

In this article, we will focus particularly on four important types of equipment: ball valves, globe valves, butterfly valves, and steam traps.

1. Ball Valve – For Quick Opening and Closing

Ball valves control flow by rotating a perforated ball located inside the valve body.

The valve can be fully opened or closed with a 90-degree movement of the handle. For this reason, ball valves are particularly useful in lines where quick opening and closing operations are required.

Advantages of ball valves in steam systems

• Provide quick opening and closing.

• Can offer low flow resistance in the fully open position when properly designed.

• Compact designs are available.

• Can provide practical solutions in terms of maintenance and operation.

• Available with different connection and body material options.

However, the primary purpose of a ball valve is generally not to provide proportional flow adjustment, but to open or close the line.

Therefore, instead of continuously operating a ball valve in a partially closed position, it should be evaluated whether the application actually requires flow control.

Where can ball valves be used?

Depending on the application, ball valves can be used in steam systems:

• At equipment inlet and outlet points,

• At line isolation points,

• To isolate specific sections of a line during maintenance,

• In auxiliary steam lines.

2. Globe Valve – For Applications Requiring Flow Control

Globe valves are designed to control flow by changing the movement of the fluid through the valve and the available flow passage.

Unlike ball valves, globe valves can be a more suitable solution in applications where flow needs to be controlled gradually, depending on the design.

It is important to select the appropriate valve type when a specific flow rate needs to be maintained or the flow needs to be adjusted in a controlled manner within the process.

Key features of globe valves

• Designs suitable for flow control are available.

• Gradual opening and closing can be achieved.

• Can be used in control applications.

• Models suitable for steam, hot water, and various industrial fluids are available.

However, due to the design of globe valves, pressure loss should also be considered during valve selection for certain applications.

When should a globe valve be preferred?

For example, if a steam line requires not only completely shutting off the steam, but also controlled adjustment of the steam flow rate, a globe valve can be considered.

The important point is that the valve should not be selected based solely on its name. Flow rate, pressure, temperature, and control requirements should be evaluated together.

3. Butterfly Valve – A Practical Solution for Large-Diameter Lines

Butterfly valves control flow by rotating a disc located inside the valve body.

Due to their compact design and relatively low weight, they can provide practical solutions, particularly in large-diameter pipelines.

Butterfly valves are available with different body, disc, and sealing materials. Therefore, when selecting a model for steam applications, the product's temperature and pressure limits must be checked.

Advantages of butterfly valves

• Compact design

• Low weight

• Economical solution for large diameters

• Quick opening and closing

• Manual or actuator-operated options

Butterfly valves can provide advantages in terms of space and installation, especially in large-diameter lines.

However, not every butterfly valve is suitable for steam applications.

The valve's temperature resistance, sealing material, pressure class, and operating conditions specified by the manufacturer must always be checked.

4. Steam Trap – Manages Condensate, Not Steam

A steam trap differs from the other three types of equipment in an important way.

The primary function of a steam trap is to automatically discharge condensate generated in the steam system while keeping live steam within the system as much as possible.

Therefore, it would not be correct to consider a steam trap simply as a conventional "line isolation valve."

İsimatik's previously published content on steam traps also explains that steam traps help discharge condensate while retaining live steam in the system, thereby contributing to heat transfer, energy efficiency, and the management of water hammer risks.

Why is a steam trap necessary?

If condensate is not properly removed from a steam line:

• Heat transfer performance may decrease.

• The risk of water hammer may increase.

• Corrosion may occur in pipes and equipment.

• Steam system efficiency may decrease.

• The operating conditions of equipment may be adversely affected.

Therefore, proper steam trap selection is important, particularly in applications such as heat exchangers, steam lines, drying equipment, and process equipment.

Differences Between Ball Valves, Globe Valves, Butterfly Valves, and Steam Traps

These four products are not used for the same purpose.

The most important point here is:

A steam trap is not an alternative to a ball valve or butterfly valve.

This is because the function of a steam trap is not to manually open and close the line, but to properly discharge condensate generated in the steam system.

Which Valve Should I Choose for a Steam System?

To select the right valve, the first step is to determine what function the valve will perform in the system.

If quick opening and closing is required

A ball valve can be considered.

It can be a suitable product group, particularly when a specific section of the line needs to be isolated for maintenance or when the flow needs to be shut off quickly.

If controlled flow adjustment is required

A globe valve or an application-specific control valve should be considered.

Flow rate and pressure conditions should also be calculated in this case.

If a compact solution is required for a large-diameter line

Butterfly valve options can be evaluated.

However, the temperature and pressure ratings of the butterfly valve intended for steam service must always be checked.

If condensate forms in the steam line

A steam trap should be considered.

When selecting a steam trap, looking only at the DN size is not sufficient. Operating pressure, temperature, condensate flow rate, and application conditions should be taken into account.

6 Technical Criteria to Consider When Selecting a Steam Valve

1. Operating Pressure

The pressure class of the valve must be compatible with the operating pressure of the system.

The PN value alone is not sufficient as a selection criterion; actual operating conditions and the manufacturer's technical specifications should be evaluated together.

2. Operating Temperature

Temperature is one of the most important criteria when selecting a valve for steam applications.

The temperature resistance of sealing elements should be checked, particularly in high-temperature applications.

3. Valve Diameter

The DN value should be compatible with the pipeline.

However, simply selecting a valve with the same diameter as the existing pipe may not always provide the correct result. Steam flow rate and flow conditions should also be evaluated.

The potential for incorrect valve sizing to cause issues such as pressure imbalance and energy losses in steam systems is also addressed in İsimatik's existing content.

4. Valve Function

Ask yourself:

“What will this valve do in the system?”

• Will it open and close?

• Will it control the flow?

• Will it isolate the line?

• Will it discharge condensate?

• Will it reduce pressure?

The answer to this question plays a fundamental role in determining the valve type.

5. Material and Sealing

The body material and gasket/sealing elements must be suitable for the temperature and pressure conditions of the steam.

Particularly in high-temperature applications, it should not be assumed that a standard valve can be used directly.

6. Connection Type

Different connection options may be available, such as threaded, flanged, or wafer connections.

The existing piping system and installation conditions should be considered during selection.

Is a Single Valve Type Sufficient for Steam Systems?

In most industrial steam systems, using a single valve type to meet all requirements is not the right approach.

For example, different equipment may be used for different functions in a steam line:

Ball valve → Isolation

Globe or control valve → Flow control

Butterfly valve → Opening and closing in large-diameter lines

Steam trap → Condensate discharge

Therefore, there is no single answer to the question, “What is the best steam valve?”

The real question should be:

“Which valve is right for my application?”

Conclusion: The Right Steam Valve Is Selected According to the Application

Valve selection in steam systems should not be based solely on product price or pipe diameter.

Ball valves, globe valves, butterfly valves, and steam traps are equipment designed for different purposes.

Ball valves can be considered for quick opening, closing, and isolation applications; globe valves for applications where controlled flow is important; and butterfly valves as a practical solution, particularly for large-diameter lines. Steam traps, on the other hand, focus on removing condensate generated within the system.

For the correct selection, pressure, temperature, flow rate, DN size, fluid properties, valve function, and connection type should be evaluated together.

İsimatik provides valves and flow control equipment suitable for various applications in industrial facilities. You can evaluate product options according to your technical requirements to determine the right solution for your steam system.