Upstream Wellhead and Christmas Tree | Isolation and flow control for production tubing, annulus outlets, choke lines and well-testing equipment. | Gate valves Slab gate valves Expanding gate valves Choke valves | Positive isolation, pressure control and controlled well production. | Carbon steel, low-alloy steel, stainless steel and corrosion-resistant alloys where sour service requires additional resistance. | High-pressure service is common. Temperature depends on reservoir conditions, produced fluids and well depth. | Manual handwheel, hydraulic actuator or pneumatic actuator. Hydraulic actuation is common for remote or emergency operation. | Verify pressure rating, bore configuration, sour-service suitability, erosion resistance, sealing arrangement and emergency shutdown requirements. | API 6A, NACE MR0175 / ISO 15156, API 6FA and applicable ASME pressure-design requirements. |
Upstream Flowlines and Gathering Systems | Gathering multiphase oil, gas and produced water from wells to separators, treatment units or central processing facilities. | Ball valves Full-bore gate valves Check valves Plug valves | Pipeline isolation, pig passage, backflow prevention and sectional shutdown. | Carbon steel, stainless steel, duplex stainless steel and nickel-based alloys for aggressive fluids. | Pressure and temperature vary significantly with field conditions. Multiphase flow may cause erosion, flashing and hydrate formation. | Manual, pneumatic or electric actuator. Pneumatic actuation is widely used where instrument air or gas is available. | Select a piggable full-bore design where required. Consider sand content, water cut, wax, hydrates, fugitive emissions and low-temperature toughness. | API 6D, API 6FA, API 598, ASME B16.34 and NACE MR0175 / ISO 15156 when applicable. |
Upstream Separation and Production Treatment | Three-phase separators, heater treaters, free-water knockouts, produced-water systems and gas-liquid separation. | Globe valves Control valves Butterfly valves Ball valves Check valves | Throttling, level control, pressure control, isolation and prevention of reverse flow. | Carbon steel, stainless steel, duplex stainless steel and lined materials for corrosive or abrasive services. | Control valves may experience pressure drop, flashing, cavitation or erosive multiphase flow. | Pneumatic diaphragm or piston actuators for control; electric or pneumatic actuators for isolation. | Size control valves using actual flow, density, viscosity, vapor pressure and differential pressure. Check trim materials for erosion and cavitation. | IEC 60534 for control valves, API 598, ASME B16.34 and relevant process piping standards. |
Midstream Transmission Pipelines | Long-distance crude oil, refined-product and natural-gas transmission pipelines, including compressor and pump stations. | Trunnion-mounted ball valves Floating ball valves Slab gate valves Check valves | Rapid isolation, sectionalizing, pigging, line pressure management and prevention of reverse flow. | Carbon steel is common; stainless steel and corrosion-resistant alloys may be selected for specific fluid or environmental conditions. | Valve class and temperature rating must match the pipeline design pressure, operating envelope and low-temperature conditions. | Pneumatic gas-over-oil, hydraulic, electric or electro-hydraulic actuators. Fail-safe operation may be required. | Confirm full-bore dimensions, double-block-and-bleed capability, fire-safe performance, anti-static design, fugitive-emission control and actuator torque. | API 6D, API 6FA, API 607 where applicable, ASME B16.34 and pipeline design codes such as ASME B31.4 or B31.8. |
Midstream Natural Gas Processing | Inlet separation, dehydration, sweetening, acid-gas removal, fractionation and residue-gas handling. | Ball valves Globe control valves Butterfly valves Plug valves Check valves | Gas isolation, pressure reduction, flow control and prevention of compressor or equipment backflow. | Carbon steel, stainless steel, duplex stainless steel and corrosion-resistant alloys for wet gas, amine or acid-gas service. | Gas service may involve high pressure, Joule-Thomson cooling, hydrate risk and rapid temperature changes. | Pneumatic or electric actuation. Spring-return designs are often considered for emergency shutdown duties. | Evaluate wet-gas corrosion, amine compatibility, low-temperature performance, leakage class, anti-blowout stem design and decompression resistance. | API 6D, IEC 60534, API 6FA, NACE MR0175 / ISO 15156 and applicable project specifications. |
Midstream Storage Tanks and Terminals | Crude oil, condensate, liquefied petroleum gas and refined-product storage, transfer and truck, rail or marine loading. | Floating ball valves Trunnion-mounted ball valves Butterfly valves Tank-bottom valves Emergency isolation valves | Product isolation, transfer control, loading-arm protection and tank outlet emergency shutdown. | Carbon steel, stainless steel, aluminum bronze and lined materials according to product compatibility and corrosion conditions. | Consider product vapor pressure, ambient temperature, thermal expansion, fire exposure and static electricity. | Manual, electric, pneumatic or hydraulic actuation. Remote emergency isolation is important for high-risk transfer points. | Verify fire-safe construction, antistatic continuity, low-emission packing, double isolation requirements and compatibility with tank overfill protection. | API 6FA, API 607, API 2000, API 2610, NFPA requirements and applicable tank standards. |
Downstream Refinery Crude and Vacuum Units | Crude distillation, vacuum distillation, furnace feed, residue transfer and hot hydrocarbon isolation. | Gate valves Globe valves Butterfly valves High-temperature ball valves Plug valves | Isolation, throttling, flow diversion and protection of furnaces, towers and transfer lines. | Carbon steel, stainless steel, chrome-molybdenum steel, nickel alloys and special trims for high-temperature or corrosive duties. | High temperature, thermal cycling, coking, oxidation and pressure drop must be considered. Vacuum service requires suitable stem and seat design. | Manual or electric actuation for isolation; pneumatic actuators for fast or automated service. | Assess thermal expansion, coke formation, seat reliability, refractory or catalyst carryover, fugitive emissions and fire-safe performance. | API 600, API 602, API 608, API 609, API 6FA, API 607 and ASME B16.34. |
Downstream Hydroprocessing and Hydrogen Service | Hydrotreating, hydrocracking, hydrogen recycle, high-pressure separators and sour-water systems. | Ball valves Gate valves Globe control valves Check valves | High-pressure isolation, hydrogen or hydrocarbon flow control and protection against reverse flow. | Low-alloy steel, stainless steel, austenitic stainless steel, nickel alloys and specialized hard-facing materials. | High pressure, hydrogen permeation, rapid gas decompression, high temperature and hydrogen sulfide exposure may be present. | Pneumatic or hydraulic actuation for critical isolation; electric actuation may be used where suitable power and safety systems exist. | Review hydrogen compatibility, sour-service requirements, fugitive emissions, rapid decompression resistance, trim hardness and seat leakage. | API 6D, API 608, API 623, API 6FA, NACE MR0175 / ISO 15156 and project-specific refinery standards. |
Downstream Chemical and Corrosive Process Units | Sulfur recovery, acid-gas handling, caustic systems, sour-water stripping and corrosive chemical injection. | Lined butterfly valves Lined ball valves Diaphragm valves Pinch valves Alloy globe valves | Corrosion-resistant isolation and flow control for liquids, gases, slurries and contaminated process streams. | Fluoropolymer-lined bodies, stainless steel, duplex stainless steel, nickel alloys, titanium and corrosion-resistant elastomers. | Chemical concentration, temperature, permeability, pressure cycling and solid content determine the appropriate lining and trim. | Manual, pneumatic or electric actuation. Fail-safe action may be required for toxic or highly corrosive streams. | Match all wetted materials to the chemical composition. Check permeation, vacuum capability, abrasion resistance and cleaning requirements. | API 598, ASME B16.34, IEC 60534 where control service applies and relevant chemical-resistance specifications. |
Downstream Utilities and Process Support | Cooling water, boiler feedwater, steam, instrument air, nitrogen, fuel gas and firewater systems. | Butterfly valves Gate valves Globe valves Check valves Safety relief valves | Utility isolation, throttling, pressure relief and protection of pumps, boilers, compressors and heat exchangers. | Ductile iron, carbon steel, stainless steel, bronze and suitable elastomers depending on fluid and temperature. | Steam service requires high-temperature packing and trim. Cooling-water systems require resistance to corrosion and biological fouling. | Manual, pneumatic or electric actuation. Electric actuation is common where compressed air is unavailable. | Consider water chemistry, pressure surge, steam temperature, cavitation, actuator enclosure rating and maintenance access. | API 594, API 598, ASME B16.34, MSS standards and applicable boiler, fire-protection or utility codes. |
All Stages Emergency Shutdown and Fire Protection | Emergency isolation of hydrocarbon inventories, firewater deluge, flare headers and safety-critical process equipment. | Ball valves Gate valves Butterfly valves Check valves Pressure safety valves | Rapid shutdown, inventory isolation, overpressure protection and prevention of hazardous reverse flow. | Carbon steel, stainless steel, ductile iron and corrosion-resistant alloys according to service conditions. | Equipment must remain functional during specified fire exposure, pressure surges and loss of utilities. | Spring-return pneumatic, hydraulic or electro-hydraulic actuation; manual backup may be required. | Define fail-open or fail-closed action, partial-stroke testing, fire-safe performance, SIL requirements, response time and proof-test intervals. | API 6FA, API 607, IEC 61508, IEC 61511, API 521 and applicable local fire and pressure-safety regulations. |