Butterfly Valves for Chemical & Petrochemical Applications

Acids

Acid service requires careful evaluation of every wetted valve component.

BZVF supplies butterfly valve solutions for applications involving media such as:

• sulfuric acid;

• hydrochloric acid;

• nitric acid;

• phosphoric acid;

• organic acids;

• mixed acidic process streams;

• acidic wastewater and process liquids.
   

The name of the acid alone is not sufficient for material selection.

For example, corrosion behavior can change substantially with acid concentration and operating temperature. Impurities, chlorides and other process constituents can also affect the suitability of stainless steels and other alloys.

Depending on the application, BZVF can evaluate configurations using stainless steels, titanium, Hastelloy and other corrosion-resistant alloys, as well as PTFE-based or rubber-lined sealing systems.
 

For acid service, provide us with:

• chemical name;

• concentration;

• minimum, normal and maximum temperature;

• operating and design pressure;

• contaminants or secondary chemicals;

• solids content if present;

• valve size;

• required material specification.

Our engineering team will use these conditions to select the appropriate valve construction and sealing system.

Alkalis & Caustics

Chemical, petrochemical and fertilizer plants frequently use alkaline solutions for process reactions, neutralization, cleaning and treatment.

Typical media can include:

• sodium hydroxide;

• potassium hydroxide;

• ammonia solutions;

• alkaline process water;

• other caustic process streams.

The correct material depends strongly on concentration and temperature.

For suitable lower-temperature services, soft seated or lined butterfly valves can provide reliable isolation with low operating torque.
 

For elevated temperatures, higher pressures or more demanding chemical conditions, metal seated or special-alloy configurations may be required.

BZVF selects the complete wetted material system according to the actual process conditions rather than using one standard configuration for all caustic services.

Hydrocarbons & Petrochemical Feedstocks

Petrochemical plants process a very broad range of hydrocarbon feedstocks, intermediate products and finished chemicals.

Typical applications can include:

• benzene;

• toluene;

• xylene;

• ethylene;

• propylene;

• butadiene;

• naphtha;

• condensates;

• gas oils;

• process solvents;

• other hydrocarbon streams.

For these services, BZVF offers high-performance, metal seated and triple offset butterfly valve configurations depending on pressure, temperature and required shutoff performance.

Metal seated designs are particularly suited to elevated-temperature hydrocarbons and demanding process conditions where resilient seats are unsuitable.

High-performance offset valves can provide a compact solution for moderate-temperature process applications where the selected PTFE-based seat is chemically compatible.

Where hazardous or volatile media are involved, the valve specification can also incorporate project requirements for:

• fire-safe construction;

• fugitive-emissions control;

• stem sealing;

• antistatic requirements where applicable;

• specific leakage performance;

• emergency shutdown actuation.

High-Temperature Process Media

Chemical and petrochemical plants contain numerous high-temperature applications associated with reactors, cracking units, reformers, heat exchangers, steam systems and thermal-process equipment.

Typical media can include:

• thermal oils;

• hot hydrocarbons;

• saturated steam;

• superheated steam;

• process vapor;

• heated chemical streams;

• hot gases.

For these operating conditions, BZVF generally recommends metal seated butterfly valve technology once the temperature or process conditions exceed the practical limits of resilient seat materials.

Our severe-service metal seated valves can be engineered with stainless, alloy-steel and nickel-alloy components according to operating requirements.

For particularly demanding thermal service, Inconel and other nickel-based alloys can be used for critical components such as sealing rings, stems, discs, overlays or other wetted parts depending on the valve design.

Material strength at operating temperature, thermal expansion, oxidation resistance and actuator torque are evaluated as part of the valve selection.

Cryogenic & Refrigerated Media

Chemical and petrochemical processes can also operate at very low temperatures.

Applications may involve:

• liquid ethylene;

• refrigerated ammonia;

• liquefied hydrocarbon gases;

• cryogenic process liquids;

• low-temperature chemical storage and transfer.

Cryogenic service requires more than simply changing the seat material.

Thermal contraction affects the body, disc, shaft, sealing surfaces and packing arrangement. Materials must also retain sufficient mechanical properties at the minimum design temperature.

BZVF can engineer cryogenic butterfly valve configurations for demanding low-temperature applications using appropriate stainless steels, special alloys and metal sealing systems.

For cryogenic chemical applications, provide:

• process medium;

• minimum design temperature;

• normal operating temperature;

• pressure;

• valve size;

• required pressure class;

• end connection;

• actuation requirements;

• applicable project or testing standard.

Our engineering team will select the appropriate valve materials, construction and sealing system.

Slurries & Viscous Chemicals

Chemical plants also handle media containing suspended solids, catalysts, pigments, polymers and other abrasive or viscous materials.

Typical applications include:

• catalyst slurries;

• titanium dioxide slurry;

• polymer slurry;

• pigment suspension;

• lime slurry;

• fertilizer slurry;

• viscous chemical products;

• contaminated process fluids.

These applications create both chemical and mechanical challenges.

Particles can cause erosion and abrasion, while the liquid phase can attack the valve materials chemically.

BZVF rubber-lined butterfly valves are designed specifically for corrosive, abrasive and slurry-type applications.

Different lining, disc and sealing materials can be selected according to:

• chemical composition;

• particle size;

• solids concentration;

• flow velocity;

• temperature;

• pressure;

• operating frequency.

For especially aggressive slurry service, we can also evaluate metal or special-alloy wetted components where appropriate.

Urea & Fertilizer Service

BZVF manufactures valves for fertilizer and urea process applications, including services requiring special corrosion-resistant materials.

Urea production presents particularly demanding corrosion conditions, especially within the high-pressure synthesis section where ammonium carbamate-containing process media can be extremely aggressive.

Valve selection must therefore follow the specific process location and project or licensor material specification.

Depending on the application, BZVF can manufacture valve configurations using:

• 316L and specified urea-grade stainless steels;

• 316Ti;

• titanium;

• special high-alloy stainless steels;

• Hastelloy;

• nickel-based alloys;

• other corrosion-resistant materials specified by the project.
   

Where the project specifies materials such as 316L Urea Grade or 25-22-2 / UNS S31050, this should be identified at the enquiry stage so that we can confirm the exact material specification, manufacturing requirements and required documentation.

Different areas of a fertilizer or urea plant have very different operating environments. We therefore do not recommend one universal material for every urea application.

Send us the process datasheet, project specification or licensor requirements and our engineering team will evaluate the correct valve construction.

Water & Plant Utility Systems

Chemical and petrochemical plants also depend on extensive utility networks.

Applications include:

• cooling water;

• seawater;

• demineralized water;

• process water;

• firewater;

• wastewater;

• flushing systems;

• compressed-air systems;

• utility gases.

These applications often allow more economical valve configurations than the main process lines.
 

Depending on the media, BZVF can supply concentric, double offset, rubber-lined and high-performance butterfly valves for utility service.
 

For seawater and highly chloride-containing systems, we can also evaluate titanium, brass, bronze and other suitable copper or corrosion-resistant alloy configurations according to the actual water chemistry.

The objective is to use severe-service materials where they are necessary while avoiding unnecessary cost where operating conditions permit a simpler valve design.

Recommended Butterfly Valve Types

Metal Seated Butterfly Valves

BZVF metal seated butterfly valves are designed for severe chemical and petrochemical service involving elevated temperatures, high pressures, aggressive media or demanding isolation requirements.

Depending on the project, we can manufacture metal seated configurations in carbon steel, stainless steel, alloy steel and special corrosion-resistant materials.

The sealing system can also incorporate stainless steels, nickel alloys and other engineered materials according to the service.

Metal seated butterfly valves are particularly suitable where conventional elastomer or PTFE seat materials cannot meet the pressure, temperature or process requirements.

Recommended for:

• high-temperature chemical processes;

• hot hydrocarbons;

• steam;

• high-pressure service;

• severe chemical conditions;

• thermal cycling;

• demanding process isolation.

Triple Offset Butterfly Valves

Triple offset butterfly valves are one of the primary BZVF solutions for severe chemical and petrochemical isolation.

The three-offset geometry minimizes rubbing between the disc sealing element and body seat through most of the operating cycle. This reduces friction and wear on the sealing surfaces compared with conventional designs.

The metal-to-metal sealing configuration makes triple offset valves particularly suitable for:

• elevated temperature;

• severe thermal cycling;

• hydrocarbons;

• steam;

• hazardous media;

• high-pressure process service;

• applications requiring durable metal sealing.

For special chemical environments, BZVF can combine triple offset technology with corrosion-resistant materials such as stainless steel, Hastelloy, Inconel and other specified alloys.

High Performance Butterfly Valves

High-performance butterfly valves use offset geometry to reduce seat friction and operating torque while providing reliable isolation.

BZVF can manufacture high-performance butterfly valve configurations using PTFE-based and other suitable sealing systems according to the operating conditions.

These valves provide an efficient solution where a standard concentric butterfly valve is insufficient but a full metal seated severe-service valve is unnecessary.

Depending on the material compatibility, they can be applied to:

• hydrocarbons;

• process chemicals;

• solvents;

• utility fluids;

• moderate-temperature corrosive service;

• petrochemical process lines.

Rubber-Lined Butterfly Valves

BZVF rubber-lined butterfly valves are engineered for corrosive, abrasive and slurry applications.

Our available configurations include multiple elastomer and lining materials to match different chemical and mechanical conditions.

Depending on the service, sealing and lining options can include:

• EPDM;

• NBR;

• FKM / Viton;

• silicone;

• chloroprene rubber;

• natural rubber;

• other application-specific compounds.

The combination of lining, body, disc and seat material is selected according to corrosion, abrasion, temperature and solids content.

Recommended for:

• chemical slurries;

• fertilizer slurries;

• corrosive wastewater;

• abrasive process streams;

• selected acids and alkalis where the chosen lining is compatible;

• utility and process-water applications.

Double Offset Soft Seated Butterfly Valves

Double offset soft seated butterfly valves provide low-friction operation and reliable shutoff for moderate-temperature and medium-pressure applications.

The offset geometry reduces compression and wear of the seat during operation compared with basic concentric designs.

These valves are especially useful for:

• cooling water;

• process water;

• utility systems;

• selected chemical services;

• wastewater;

• lower-temperature plant systems.

Multiple seat materials are available so the valve can be matched to the actual process medium.

Materials & Sealing Selection

In chemical and petrochemical service, material selection is part of the valve design.

BZVF manufactures valves in a broad range of standard and special materials so that we can match the wetted components to the specific process conditions.

Our material capability includes:

• carbon steel;

• alloy steel;

• 304 / 304L stainless steel;

• 316 / 316L stainless steel;

• 316Ti;

• titanium;

• Hastelloy;

• Inconel;

• brass;

• bronze and other copper alloys;

• additional corrosion-resistant alloys according to project specifications.

We can also combine different materials within one valve.

The body does not always need to be manufactured from the same alloy as every wetted internal component. Depending on the application, we can engineer a pressure-containing body in one material with a higher-alloy disc, shaft, seat, sealing ring, overlay or other critical component.

This allows us to optimize corrosion resistance, mechanical performance and project cost.

Stainless Steels

BZVF manufactures butterfly valves using a wide range of stainless steels.

Available options include grades such as:

• 304;

• 304L;

• 316;

• 316L;

• 316Ti;

• other specified stainless and high-alloy grades.

316 and 316L provide good corrosion resistance across many chemical and utility applications.

316Ti is titanium-stabilized stainless steel and can be specified for applications where stabilized stainless construction is required, particularly when elevated-temperature exposure is part of the process or project specification.

For more demanding chemical environments, we can move beyond conventional stainless steel to titanium, Hastelloy, Inconel and other special alloys.

Titanium

BZVF can manufacture butterfly valves and critical wetted components in titanium for highly corrosive services.

Titanium provides excellent corrosion resistance in many chloride-containing and oxidizing environments and can be particularly valuable for applications involving:

• seawater;

• brines;

• chloride-rich process streams;

• chlorine-related processes;

• selected acids;

• fertilizer production;

• corrosive chemical utilities.

Titanium Grade 2 and other specified grades can be evaluated according to the process conditions and project requirements.

Where titanium is required, we review not only chemical compatibility but also pressure, temperature, mechanical requirements, fabrication and the construction of mating components.

Hastelloy

For highly corrosive chemical environments, BZVF can manufacture butterfly valve components and special configurations using Hastelloy.

Depending on the project specification, materials can include Hastelloy C-276 and other grades.

These nickel-based corrosion-resistant alloys are frequently selected where conventional stainless steels do not provide sufficient resistance to aggressive chemical environments.

Potential applications include:

• strong acids;

• mixed acids;

• chloride-containing chemicals;

• highly corrosive process streams;

• fertilizer production;

• chemical reactors;

• aggressive petrochemical media.

Hastelloy can be used for complete wetted constructions or for selected components such as the disc, shaft, seat, sealing ring or corrosion-resistant trim.

Inconel

BZVF also manufactures valve components and severe-service configurations using Inconel and other nickel-based high-temperature alloys.

These materials combine corrosion resistance with strong mechanical properties at elevated temperature.

Depending on the valve configuration, Inconel may be used for:

• sealing rings;

• valve seats;

• discs;

• stems and shafts;

• corrosion-resistant overlays;

• high-temperature trim;

• other critical wetted components.

Inconel is particularly relevant for severe petrochemical, refinery, thermal and high-temperature chemical applications.

For metal seated butterfly valves, nickel-alloy sealing components can provide excellent durability under repeated temperature cycling.

Brass, Bronze & Copper Alloys

BZVF can manufacture selected valve components and configurations using brass, bronze and other copper alloys.

These materials can be considered for:

• water systems;

• seawater;

• marine applications;

• utility systems;

• selected chemical processes;

• applications requiring specific corrosion properties.

For seawater applications, suitable bronze and copper-alloy configurations can be evaluated according to pressure, temperature, flow velocity and water chemistry.

We select the exact copper alloy according to the application rather than treating all brass or bronze materials as interchangeable.

Carbon & Alloy Steels

Carbon and alloy steels remain a robust and economical choice for many petrochemical applications where the process conditions do not require full corrosion-resistant alloy construction.

Typical applications include:

• hydrocarbons;

• steam;

• thermal fluids;

• process gas;

• refinery utilities;

• elevated-temperature systems.

For services requiring additional internal corrosion resistance, higher-alloy trim, sealing components or overlays can be combined with a carbon or alloy-steel pressure-containing body where appropriate.

Metal Sealing Systems

Metal seated construction is our preferred solution for severe process conditions involving:

• high temperature;

• elevated pressure;

• frequent thermal cycling;

• severe hydrocarbons;

• applications where elastomeric seats are unsuitable;

• demanding service life requirements.

Depending on the project, sealing components can be manufactured from stainless steels, nickel alloys, hard-faced materials and other engineered alloys.

Combined with triple offset geometry, this design minimizes rubbing between the sealing surfaces and provides durable performance over repeated operating cycles.

PTFE & Fluoropolymer Sealing

PTFE-based seat systems provide excellent chemical resistance for many chemical-processing applications.

Depending on the valve design and operating conditions, BZVF can provide PTFE-based or reinforced sealing configurations for selected:

• acids;

• alkalis;

• solvents;

• hydrocarbons;

• chemical intermediates;

• utility fluids.

No polymer is universally suitable for every chemical, temperature and pressure combination.

We therefore verify the complete process conditions before selecting the final sealing material.

Elastomers & Rubber Linings

BZVF provides multiple elastomeric sealing and lining options across our soft seated and rubber-lined butterfly valve ranges.

Available materials can include:

• EPDM;

• NBR;

• FKM / Viton;

• silicone;

• CR / chloroprene;

• natural rubber;

• other specified compounds.

Each has different resistance to oils, acids, alkalis, water, temperature and abrasion.

We select the compound based on the actual chemical composition and operating conditions—not simply by specifying "rubber seat."

Urea Service Materials

BZVF manufactures valves for urea and fertilizer-process service.

High-pressure urea synthesis environments require particularly careful material selection because ammonium carbamate-containing process media can create severe corrosion conditions.

Depending on the process location and project specification, BZVF can manufacture valves using:

• special urea-service stainless steels;

• 316Ti for appropriate duties;

• titanium;

• high-alloy stainless steels;

• Hastelloy;

• nickel-based alloys;

• other specified corrosion-resistant materials.

Where the project requires 316L Urea Grade, 25-22-2 / UNS S31050 or another specified urea-service alloy, provide the material and licensor specification with the enquiry.

We will evaluate the exact material requirements, valve construction, manufacturing requirements, inspection and documentation as part of the engineering process.

We do not treat ordinary stainless steel as automatically suitable for severe urea synthesis service. The specified urea-service grade and project requirements must be followed.

Material Selection by Process Conditions

We do not recommend selecting materials from a generic corrosion chart alone for critical chemical service.

For an accurate recommendation, provide:

• complete chemical composition;

• concentration;

• pH;

• chloride content where applicable;

• solids concentration;

• particle size;

• normal operating temperature;

• maximum temperature;

• minimum temperature where applicable;

• operating pressure;

• design pressure;

• flow conditions;

• expected operating cycles;

• required design life;

• project or process-licensor material specification.

Our engineering team will review these conditions and select the appropriate body, disc, shaft, seat, sealing ring, lining and trim materials.