Chemical industry valves: types, applications and certifications

Chemical industry valves are components for the control of aggressive, corrosive, hazardous and flammable fluids, designed to ensure sealing and reliability in a sector where no error is allowed.

Understanding which types of chemical valves exist, where they are used and which certifications are required is the first step toward a safe and compliant supply. What's more, in these plants the choice does not concern the valve alone, but the entire valve-actuator package that drives its operation.

Types of chemical industry valves

In the chemical industry, ball valves are used above all, in their various executions, alongside angle seat valves.

The ball valve can perform two different functions. In its most common configuration it works as a shut-off ball valve, ensuring safe isolation of fluids. As a 3-way ball valve, instead, it also acts as a diverter valve: it does not merely shut off the flow, but diverts its direction toward different paths of the plant.

Industrial ball valves differ by construction: the split body ball valve (such as the PROCHEMIE 60, a stainless steel ball valve, and the THOR), the wafer and split-wafer version (MAGNUM), the trunnion ball valve for high pressure (SUPREME) and the 3-piece ball valve (424). Most are flanged ball valves with RF connections, available in full bore or reduced bore.

The ARES pneumatic angle seat valve completes the range, dedicated to utilities.

Applications of the chemical valves

Chemical industry valves come into play at every stage of the process, with applications spanning from petrochemical to pharmaceutical, from paint & coatings to the wider process industry. The main ones are:

• Raw material storage and transfer, with transfer and dosing of solvents, acids and alkalis.

• Feed and discharge of reactors, chemical dosing and batch processes.

• Tank farms and vessels: isolation, recirculation and nitrogen blanketing.

• Utilities: steam, thermal oil, cooling water and compressed air.

• Separation and treatment: distillation, evaporation, crystallization and filtration.

• CIP lines, chemical cleaning and safety and emergency systems.

For more specific needs, special executions are available: inclined-stem tank-bottom ball valves, 3-way trunnion executions or high-alloy executions, chosen according to compatibility with the fluid.

Certifications for the chemical industry valves

In the chemical sector, certifications guarantee that the valve maintains sealing and safety over time. The most relevant are TA-Luft and fugitive emission according to ISO 15848-1, which certify the control of fugitive emissions: the PROCHEMIE 60, for example, is TA-Luft certified for 60,000 cycles.

To these are added SIL up to SIL3 for functional safety, Fire Safe for fire scenarios, ATEX / Ex CE-UKCA for potentially explosive atmospheres and PED for pressure equipment. The AD2000 HP0/A4 is also available on the PROCHEMIE 60.

For hazardous areas there are dedicated ATEX ball valves and ATEX pneumatic actuators, so that the entire actuated valve meets the highest requirements.

Why valve and actuator should be chosen together

In a chemical plant the valve never works alone: it is the valve-actuator package, as a whole, that determines sealing and process continuity. An undersized or poorly matched pneumatic actuator, in fact, compromises even the best stainless steel ball valve.

The difference lies in integrated engineering, and that is exactly what OMAL does: it designs and manufactures both the valves and the pneumatic actuators in-house. Because body and control come from the same facility, OMAL verifies the correct valve actuator matching in the factory and supplies the pneumatic actuated ball valve already sized and tested, with a single technical contact.

OMAL selects the pneumatic valve actuators based on the control: the AGO rotary pneumatic actuator of the scotch yoke type, available as a double-acting pneumatic actuator or spring-return, the RACKON rack-and-pinion and the Heavy Duty executions up to 32,000 Nm.

Do you want to explore the complete range of valves and actuators for the chemical and pharmaceutical industry? Click here and discover OMAL's certified solutions.

FAQ: Frequently asked questions about chemical industry valves

Which are the best valves for the chemical industry?

There is no single best valve: it depends on the application. In the chemical industry, ball valves are used above all — such as the split body stainless steel PROCHEMIE 60, the THOR, the MAGNUM, the SUPREME as a high pressure ball valve in the trunnion version and the 424 3-piece ball valve — together with the ARES angle seat valve for utilities.

What features must chemical industry valves have?

Chemical valves must ensure tight shut-off on aggressive and corrosive fluids, resistant materials such as stainless steel or high-alloy, high stem tightness, reliability in high-cycle operation and the certifications required by the sector (TA-Luft, fugitive emission, SIL, Fire Safe, ATEX, PED).

Which shut-off valves are used for corrosive fluids?

The most common solution is the shut-off ball valve in stainless steel, with seats in modified PTFE or PEEK. For the most aggressive fluids, high-alloy executions are used, chosen according to chemical compatibility with the process fluid.

Are there Italian manufacturers of chemical industry valves?

Yes. OMAL designs and manufactures in-house in Italy both the valves and the pneumatic actuators, with over 45 years of experience since 1981 and a highly automated production that ensures consistent quality and fast lead times.

Who to contact to buy chemical industry valves?

It is best to choose a supplier that designs valve and actuator in-house and holds the sector's certifications. OMAL supplies valve-actuator packages already sized and tested, with a single technical contact for the entire package.