Industries are calling for proven low emission valves

It is often said that change is the only constant. This maxim certainly holds true for the process industries… the final products may appear to be the same, but the technology used to produce them continues to evolve, helping to make processes inherently safer, less energy intensive and with a lower environmental footprint.

Discussing this change, Souvik Saha (Industry manager, Refining and Chemicals, Valmet’s Flow Control business) draws attention to international standards. “Over time, and especially since the 2020’s, global emission norms and testing standards have evolved substantially. Today, industries are embracing stricter and tighter regulations. We see this in our customers, who are becoming more sensitive to mitigating emissions, leveraging the recognized benefits.”

Giving examples, Saha notes that clients are aiming to reduce the direct footprint of hazardous, obnoxious gases and vapors into the environment, as well as to address the indirect emissions of carbon dioxide derived from operating energy-intensive automation equipment and electronic devices. “Apart from this, from a processing industry perspective what also matters is improving upon the process economics with a gradual reduction of production losses due to leakages from this critical process equipment.”

On-site health and safety concerns are another major driver behind the quest for reduced fugitive emissions, says Saha. “For example, reducing hydrogen sulfide levels in the air allows staff to safely work for longer periods in areas previously known to have a high concentration of this hazardous chemical. In addition to being extremely toxic, hydrogen sulfide is highly flammable. A leak from a valve packing could auto ignite and cause barely detectable flames, inflicting an enormous health, safety and environmental issue at a process plant.”

Valmet clients are also keen to drive down emissions to prevent loss of product, continues Saha. “A low fugitive emission design minimizes the costs occurring when product is lost via leaking valves. Moreover, the loss of flow medium also means lost energy, since pumps or compressors are required to operate for longer to compensate for the leakage.”

Commitment to standards and regulations

Achieving the many benefits outlined above requires arresting micro-leakages from critical process valves over time. To mitigate these emission issues, the industry has adopted practices and published numerous regulatory standards for industrial valves and automated valve controllers.

The essence of a fugitive emission design lies in the body gasket, shaft seal, and materials selection. Key factors include compression force especially on the packing rings, bore and shaft surface roughness, and balancing these parameters effectively.

Tommi Bergström (Senior manager, Technology, Valmet’s Flow Control business) picks up the story: “API 622 is one such standard, focusing on process valve packings to qualify emission control performance over a specified temperature range by keeping leakage rates within permissible limits. Similarly, API 624 & API 641 define type testing requirements and acceptance criteria for fugitive emission of rising and rising-rotating stem valves, and quarter turn valves respectively.”

One of the most widely adopted standards is ISO 15848, which Bergström says has separate procedures for type testing (i.e. ISO 15848-1) and production testing (ISO 15848-2). “The type testing procedure defines a performance class which includes i) Leakage rates classified from level A (most stringent) to C; ii) Endurance class classified differently for on-off and control valves ranging from CO3/CC3 (most stringent to CO1/CC1) and iii) Stem seal adjustment classified from SSA1, SSA2 and so forth. 

This standard does not regulate valve design but instead defines type approval tests that designs must pass, aiming to establish a global emission standard.”

Bergström concludes: “In addition to these recognized standards, many end-users define their own testing criteria and requirements based on specific process needs, often going beyond published standards. All such standards are designed to prevent accidental releases of hazardous process media, which threaten health, increase safety risks, and harm the environment.”

Leadership in emission mitigation

Valmet’s Flow Control business has long led the way in emission mitigation. In 2002, it became the first valve manufacturer to obtain fugitive emission type approval for its control valves in accordance with Shell’s MESC SPE 77/312 specification. “This was achieved by focusing on rotary valve designs such as segment, eccentric plug, and eccentric disc (triple offset) types with live-loaded, low-emission packings. With these, emissions from control valves were reduced to 1/100th of those from linear valves,” states Bergström.

Saha adds that Valmet has also addressed Scope 2, i.e. the indirect emissions through its energy-efficient intelligent valve controllers. “These solutions support automated on/off and control valves with seamless health monitoring, optimized energy use (especially compressed air), real-time emission management, and predictive maintenance—ensuring that the investment more than pays for itself.”

Conceptualizing, designing and manufacturing performance

With years of experience, Valmet understands that selecting the right valve for a critical application depends on accurately assessing the severity of that application. Bergström: “This classification considers not only process parameters such as pressure and temperature, but also factors like toxicity, corrosivity, explosion risk, thermal cycling, operational cycles, and material compatibility with the medium.”

Bergström further notes that to develop and qualify valves for demanding applications, manufacturers must invest heavily in research, design, development, and testing. Continuous innovation and robust R&D processes ensure products meet strict performance criteria and withstand extreme conditions.

Asked to explain importantissues when designing a valve with minimal fugitive emissions, Bergström immediately highlights the body gasket and shaft sealing constructions and material selection. “Key factors include compression force (especially on the packing rings), bore and shaft surface roughness, and balancing these parameters effectively.”

“Valmet has addressed Scope 2 emissions through its energy efficient intelligent valve controllers”

“Building valves with optimal emission performance requires not only sound design but also precise manufacturing, tight tolerances, and skilled supervision. Seamless collaboration between fabrication and assembly teams—identifying flaws, correcting issues, and assembling with care—ensures compliance with stringent requirements.”

Rigorous validation through testing

Like all innovative OEMs, Valmet knows that validation of a new product begins with the classic challenge: ‘Who will be the first to try it?’ Bergström: “Since valves are mission-critical components, plant operators demand proven technologies. While many valve designs have remained stable for decades, ongoing development continues to improve reliability. To qualify products for harsh applications, manufacturers need resources and expertise to prove performance under extreme conditions.”

Fire tests are performed according to industry or customer standards. Fire testing verifies that the valve stays tight enough to prevent internal or external leakage from expanding the size of the fire. 

At Valmet, testing is viewed not just as compliance with emission standards but as an integral part of development. New designs undergo extensive digital modelling and simulations to study phenomena, test new component designs and materials, and optimize performance. However, physical and mechanical testing remains essential to confirm real-world reliability.

“In-house testing facilities are critical for dependable results,” continues Bergström. “However, single tests are insufficient, so at Valmet we develop and deploy comprehensive protocols to ensure our valves withstand real-world conditions. This rigorous approach instils customer confidence.”

Be that as it may, Bergström agrees that lab test results are not the same as proven performance. “Field reliability must align with lab test results. Results are compared with actual process conditions, media, and installations to ensure consistency. Products must not only pass lab tests but also perform in real environments, underscoring Valmet’s commitment to quality and safety.”

Testing taken to extremes

In 2002, Valmet became the first valve manufacturer to obtain fugitive emission 
type approval for control valves in accordance with Shell’s MESC SPE 77/312 
specification.

Valmet puts its valves through standard performance testing for tightness, torque, pressure resistance, and extreme conditions. The test regime includes exposure to fire for extended periods or cryogenic freezing before safety and performance testing. Such tests address fugitive emission risks and are often required nowadays for valves entering the market. Fire-safe design is particularly important, providing an added layer of protection for personnel and equipment.

The ultimate goal of testing is to create trust and peace of mind, emphasizes Bergström. “Valmet achieves this through dedicated, experienced professionals and in-house R&D testing facilities that have been in operation for more than 60 years. These facilities carry out approval tests such as fire and fugitive emission and are constantly upgraded to ensure compliance with the latest standards.”

A legacy of innovation and reliability

By focusing on rotary valve designs with live-loaded, low-emission packings, emissions from control valves were reduced to 1/100th of those from linear valves.

Effective R&D and certification programs require a strong focus on development, rigorous testing, and safety. By continuously innovating and adhering to demanding protocols, manufacturers such as Valmet deliver products that meet the highest performance and safety standards. This dedication reinforces their role as trusted partners across industries.

“At Valmet, reliability is reinvented every day—new performance-enhancing features are thoroughly tested in both theory and practice before they reach the market,” says Bergström. “This unwavering focus on developing top quality products that meet evolving industry needs has positioned Valmet as a supplier of choice for flow control products such as low emission valves.”

Tommi Bergström (Senior manager, Technology, Valmet’s Flow Control business) and Souvik Saha (Industry manager, Refining and Chemicals, Valmet’s Flow Control business), spoke with KCI Editorial.