In the field of industrial valves, API standards are the golden rule for technical compliance and global market access. This chapter will deeply analyze the eleven core standards with strategic value in the API standard system to help you quickly locate the technical points. Whether you are a design engineer, a purchasing decision maker or a project manager, understanding the standards and choosing the right standards is choosing competitiveness.

1.​​General Design and Manufacturing​​

​API 600: Technical Specification for Steel Gate Valves​​

​​Core Requirements​​

• Material system:
  The valve body and valve cover are compulsorily made of ASTM standard cast steel (such as A216 WCB, A217 WC6), the valve stem uses 13Cr martensitic stainless steel (A182 F6a), and the sealing surface needs to be welded with Stellite alloy (Stellite 6), with a thickness of ≥1.6mm and a hardness of HRC ≥50.
• ​​Structural design​​:
  The valve cover is bolted (compatible with ASME B16.5 flange standard), the elastic gate structure can compensate for thermal deformation, and the rising stem design must be equipped with a visual position indicator.
• Pressure Rating:
  Covering Class 150~2500, the pressure-temperature curve must strictly match ASME B16.34.

​​Application scenarios​​

• ​​High-pressure natural gas pipelines​​: Valves above Class 600 are used in the trunk line of the West-East Gas Transmission Project.
• ​​Refinery high temperature steam​​: Gate valves made of A217 WC9 can operate for a long time at 593℃.

​​Comparison with ISO 10434​​

API 6D: Specification for Pipeline Valves

​​Key technologies​​

• Fully welded valve body:
  Eliminate the risk of flange leakage, especially suitable for buried pipelines and deep sea environments. Valve body welding must comply with ASME B31.4/B31.8 standards, and 100% of the welds must be radiographically inspected.
• ​​Pig passing capacity:
  The full-bore design requires the ball diameter to be ≥90% DN. Reduced-bore valves must be specially noted and their usage scenarios must be restricted.
• Fire safety design:
  Passed API 6FA fire test (burning for 30 minutes + water impact cooling), the valve seat seal adopts high-temperature graphite ring (temperature resistance ≥800℃).

Industry Cases

• Arctic LNG Project: API 6D Class 900 fully welded ball valve is used, which has passed 50 opening and closing cycle tests at -60℃ low temperature environment.
• Subsea pipelines: API 6DSS certified valves (supplemented with deep sea requirements), equipped with ROV interface, water depth up to 3000 meters.

​​Special working condition handling​​

• ​​Cryogenic valves​​: A350 LF2 material must pass the -46℃ Charpy impact test (impact energy ≥ 27J).
• ​​Sulfur corrosion resistance​​: The valve stem and sealing surface materials must meet the NACE MR0175 Level VI standard.

​​API 602: Compact Steel Gate Valve​​

​​Design Innovation​​

• Miniaturized structure:
  The diameter is limited to NPS 4 (DN100), and the valve body is made of an integral forged body. The height is 30% shorter than that of API 600, making it suitable for pipelines in devices with limited space.
• ​​Seal Enhancement Technology​​:
  The bellows seal option (below Class 1500) completely eliminates the risk of stem leakage and is commonly used for highly toxic media such as chlorine and hydrofluoric acid.

​​Performance Parameters​​

​​Typical Applications​​

• Hydrogenation reactor​​: Class 1500 bellows gate valve prevents H₂ leakage, and the material is upgraded to Inconel 625.
• ​​Liquefied Natural Gas​​: A352 LC3 material is used for low temperature working conditions of -196℃, and the valve stem is cryogenically treated (-196℃×8h).

2. ​​Performance test certification​​

API 598: Valve Pressure Testing

​​Core Requirements​​
As the most basic performance verification standard for API valves, API 598 stipulates the mandatory process for shell strength test and sealing performance test:

• Shell test: Use water pressure of 1.5 times the nominal pressure (PN) for 60 seconds. The valve body shall not show permanent deformation or leakage.
• ​​Sealing test​​: Use 1.1 times PN gas (nitrogen or helium) or liquid medium, and classify according to leakage rate:
  • ​​Grade A​​: Only applicable to soft-sealed valves, requiring zero visible bubbles (soft seals are absolutely tight).
  • ​​Grade D​​: The allowable leakage of metal sealed valves is ≤0.1% DN (e.g. DN300 valve allows ≤0.3L/min).

​​Test Grading Comparison​​

​​Industry Applications​​

• ​​Refinery high-pressure valves: Valves above Class 900 must pass helium mass spectrometry testing (sensitivity up to 1×10⁻⁶ Pa·m³/s).
• ​​ISO compatibility​​: API 598 Class D leak rate is equivalent to ISO 5208 Rate B (0.1×DN mm³/s), but at a higher test pressure.

API 6FA: Valve Fire Test

​​The ultimate challenge of combustion and cooling​​

1. ​​Combustion stage​​:

• Place the valve in an open flame at 750~1000℃ for 30 minutes, during which time the rated pressure must be maintained at 50%.
• Graphite seals must maintain sealing (leakage ≤ API 598 D grade).

1. Water shock test:

• Immediately after the combustion ends, use a high-pressure water gun (0.2MPa) to impact the valve to simulate a fire sprinkler.
• The temperature of the valve outer surface must drop from 1000°C to below 300°C within 1 minute.

​​Key Parameters​​

​​Differences from ISO 10497​​

Cooling method: API requires forced water cooling, ISO allows natural cooling.

Pressure maintenance: API requires pressure to be maintained during testing, while ISO allows pressure reduction.

​​Industry Preference​​: API 6FA is mandatory for offshore platforms, ISO 10497 is acceptable for onshore projects.

​​API 624: Fugitive Emissions Testing​​

​​Coping with the stringent requirements of environmental regulations​​

• ​​Test loop​​:
  The sealing performance of the valve was simulated after 300 thermal cycles (-50℃~250℃) and 3000 mechanical opening and closing operations to detect the methane leakage rate.
• Leakage classification:

​​Technological breakthroughs​​

• ​​Dual detection method​​: First use a helium mass spectrometer to locate the leak point (accuracy 1×10⁻⁶ mbar·L/s), and then use methane to simulate the actual working conditions.
• ​​Dynamic sealing test​​: Continuously monitor the leakage during the valve opening and closing process (the blind spot of traditional static testing).

Industry Impact

• EU TA-Luft certification: Class TA is required to meet the standards.
• ​​US EPA regulations​​: Chemical plants are required to provide API 624 test reports (40 CFR Part 63)

3. Wellhead and special applications

API 6A: Wellheads and Christmas Tree Valves

​​Core Requirements​​
As the core equipment standard for oil and gas production, API 6A specifies the performance requirements of wellhead valves under extreme working conditions:

• Material Grade:
  • FF grade: general corrosion-resistant material (such as A694 F60 forged steel), suitable for shallow oil and gas wells.
  • ​​HH grade​​: Materials resistant to hydrogen sulfide (H₂S) corrosion, must pass the NACE MR0175 Level VI test (duplex steel 2205 or Inconel 625).
  • ​​U Grade​​: Ultra-high strength material (yield strength ≥150 ksi), used for ultra-deep wells (≥6000 meters).
• PR2 Performance Verification:
  The valve must pass full life cycle simulation tests (including pressure cycling, temperature shock, and immersion in corrosive media) to ensure 30 years of maintenance-free operation.

​​Key Parameters​​

Industry Cases

• ​​Middle East sour gas field: Using HH-grade duplex steel valves, H₂S concentration reaches 20%, and PR2 verification cycle is shortened to 12 months.
• ​​Deep-sea subsalt oil fields: U-grade valves with titanium alloy valve bodies can withstand water depths of 3,000 meters + formation pressures of 138 MPa.

API 594: Check Valve Design and Application

​​Technological breakthroughs​​
API 594 proposes the following solutions to water hammer and medium backflow problems in oil and gas pipelines:

• ​​Double plate check valve​​:
  The split-valve disc design has a closing time of ≤0.5 seconds (the traditional swing valve disc takes 1 to 2 seconds), reducing the impact of water hammer by 90%.
• ​​Anti-surge structure​​:
  A damping spring is added to the back of the valve disc to suppress high-frequency vibration (it can still seal stably when the frequency is ≥50 Hz).

​​Comparison with other standards​​

​​Application scenarios​​

• ​​Shale gas booster station​​: Prevent fracturing fluid backflow from causing pump damage.
• Oil sand pipeline: Double plate structure can withstand the wear of solid particles (sand content in the medium ≤ 30%).

​​API 609: Butterfly Valve Technical Specifications​​

​​Design Innovation​​
As the core standard for pipeline control valves, API 609 focuses on the following key technologies:

• ​​Eccentric structure design​​:
  • ​​Triple eccentric butterfly valve​​: The contact point between the valve plate and the valve seat deviates from the center of the pipe, achieving zero friction opening and closing (torque reduced by 40%).
  • Metal seal fireproof design: The valve seat adopts Inconel 718 cladding layer, which can still seal after passing API 6FA fireproof test.
• ​​Flow resistance optimization​​:
  The flow resistance coefficient Kv value of the full-bore butterfly valve is ≥0.9 (the Kv value of the traditional butterfly valve is ≈0.6~0.8).

​​Applicable media and restrictions​​

​​Market Cases​​

• ​​North American shale gas pipeline network​​: Triple eccentric butterfly valve regulates gas pressure fluctuations, with a response time of ≤2 seconds.
• ​​Refinery catalytic cracking unit: Metal-sealed butterfly valve operated continuously for 5 years in 650℃ flue gas.

4. ​​Quality Management System​​

API Q1: Petroleum Equipment Quality System

​​Core Elements​​
As the cornerstone of the API standard system, API Q1 has established a quality management framework covering the entire life cycle of valves. Its core requirements can be summarized into three pillars:

1. Design Verification​​

• It is mandatory to verify the structural integrity of key components (such as valve body, valve cover) using finite element analysis (FEA) or prototype testing.
• Extreme working condition simulation: For example, deep-sea valves need to pass 30,000 pressure cycle tests (API 17TR8 standard).

1. ​​Process Control​​

• For key processes (such as sealing surface cladding and cryogenic treatment), SPC (statistical process control) charts need to be established to monitor parameter fluctuations in real time.
• Example: For valve stem heat treatment, the temperature curve (±5°C), holding time (≥2h) and cooling rate (≤50°C/h) need to be recorded.

1. ​​Traceability Management​​

• Material batches are traced to the furnace number of the steel mill, for example, the duplex steel 2205 valve body needs to record:
  • Smelting furnace number
  • Heat treatment batch
  • UT/MT test report number
  • ​​Comparison with ISO 9001​​

​​Certification Value​​

• ​​API Monogram Authorization​​: Companies that have passed API Q1 certification can mark the API Monogram on their products, which is essential for global oil and gas project procurement access.
• ​​Cost-effectiveness​​: Statistics show that implementing API Q1 can reduce design errors by 82% and reduce quality costs by 37%.

​​API 20E: Digital Quality Traceability Standard​​

​​Technical Architecture​​
API 20E defines a fully digital traceability system from raw materials to decommissioning and scrapping, which includes three modules:

1. ​​Data link construction​​

• Material traceability: Blockchain records the entire process of steel smelting → forging → machining (each process generates an independent hash value).
• Manufacturing records: Welding parameters (current/voltage/speed) and non-destructive testing (RT/UT) data are uploaded to the cloud in real time.

1. ​​Intelligent Analysis​​

• Predictive maintenance: AI models are trained based on historical data to provide early warning of seal aging 30 days in advance (accuracy ≥ 92%).
• Process optimization: Find the optimal combination of heat treatment parameters through big data analysis (e.g. reducing the hardness deviation from ±3HRC to ±1HRC in a certain project).

1. ​​Interactive Interface​​

• Supports OPC UA protocol and seamlessly connects with SCADA and MES systems.
• Real-time query on mobile terminal: Scan the QR code on the valve nameplate to obtain full life cycle data.

​​Implementation Cases​​

• A certain LNG project in the Middle East: Implemented through API 20E:
  • Reduce spare parts inventory by 45% (accurately predict replacement cycles)
  • Maintenance response speed increased by 60% (fault codes are directly linked to maintenance plans)
  • Carbon emissions reduced by 22% (optimized logistics routes and processing energy consumption)

More API standard chapters (5-8): “Full analysis of API valve core standards: 11 major technical systems (2)”

5. ​​Safety and emergency systems​​6. ​​Subsea and deep sea technology​​ 7. ​​Drive and control​​8. ​​Maintenance and life management​​

More chapters 9-11: “Full analysis of API valve core standards: 11 major technical systems (3)”

9. ​​Special media handling​​10. ​​Structural supplementary standards​​ 11. ​​Storage and transportation supporting standards​​

API standards are the passport to the international market. As an API fully certified manufacturer, JH Valve has a complete system that covers the entire life cycle management of oil and gas industrial valves from design, manufacturing to decommissioning, meeting the technical needs of land, sea and extreme environments. It has been focusing on the oil and gas field for 20 years, with API 6D ball valves and API 600 gate valves as the core. The sealing accuracy reaches 1/10 of the D-level standard and the service life is extended by 60%. From land Class 1500 to deep-sea API 17D, we use API 20E digital traceability to help customers pass the stringent audits in the Middle East and North America. Choosing JH Valve is not only about API compliant products, but also about engineering strength that exceeds standards.

Define competitiveness with API standards – JH Valve helps you break through globally.

5. ​​Safety and emergency systems​​

API 526: Safety valve design and selection

​​Core Features​​
Safety valves are the last line of defense for pressure in the oil and gas industry. API 526 specifies the full chain requirements from design to maintenance:

• ​​Emissions calculation​​:
  The Kd value method (discharge coefficient) is used to accurately calculate the minimum flow area to ensure that the discharge capacity during overpressure is ≥ the maximum gas production of the system.
  Formula: Where A is the throat area (in²), W is the mass flow rate (lb/h), C is the gas constant, and P1 is the set pressure (psi).

• ​​Opening and closing pressure difference control​​:
  The opening and closing pressure difference is required to be ≤7% of the set pressure to prevent frequency jumping (high frequency opening and closing causes wear of the sealing surface).

​​Technical Parameters Comparison​​

​​Industry Applications​​

• ​​Refinery reactor: Class 900 spring-loaded safety valve, set pressure 25MPa, discharge temperature 550℃.
• LNG storage tank: pilot operated safety valve, the sealing material is polytetrafluoroethylene composite graphite under low temperature conditions (-162℃).

​​API 14D: Wellhead Safety Valve System​​

​​Emergency Response Mechanism​​
Wellhead safety valve (SSSV) is the core equipment to prevent blowout. Its design must meet the following requirements:

• ​​Fast Shutdown​​:
  It takes ≤ 2 seconds from signal triggering to complete closure, which can cut off the 30,000psi high-pressure oil and gas flow in an emergency.
• ​​Fail-safe mode​​:
  When the hydraulic control circuit fails, the spring energy storage mechanism automatically triggers the shutdown (Fail-Safe Close).
• ​​SIL Certification​​:
  The safety level must reach SIL3, and the failure probability must be ≤1×10⁻⁷times/hour (verified by Hazard and Operability analysis).

​​Key test items​​

​​Case Study: Improvements after the Gulf of Mexico accident​​

• ​​Redundant design​​: Add dual hydraulic control circuits, and the circuit can still be shut down if a single circuit fails.
• ​​Remote triggering​​: Activate the shutdown procedure through underwater sonar signals (≤3000m), and the response time is shortened to 1.5 seconds.

API 6F: Valve fire test

​​Extreme environment verification​​
API 6F simulates the valve performance under fire scenarios, and the technical requirements are divided into three stages:

1. ​​Combustion stage​​:

• Open flame temperature ≥ 2000℉ (1093℃) for 30 minutes, during which the valve is subjected to 110% PN pressure.
• Graphite seals must maintain sealing (leakage ≤ API 598 D grade).

1. Shock Cooling​​:

• The high-pressure water gun (0.2MPa) directly sprays the high-temperature valve body, and the surface temperature drops from 2000℉ to 400℉ within 1 minute.

1. Functional testing:

• After cooling, operate the valve 10 times with a torque increase of ≤20%.

​​Material Selection Guide​​

6. Subsea and deep sea technology

​API 6SS: Supplementary Specification for Subsea Valves​​

​​Technical challenges in extreme environments​​
Deep-sea valves need to withstand the combined challenges of high pressure, low temperature, corrosion and ROV (underwater robot) operation. API 6SS sets special requirements for this:

• ​​Pressure compensation design​​:
  • The valve body wall thickness is increased by 20% (compared to the same level of land valves), and the compressive strength at a water depth of 5,000 meters (≥690 bar) is verified by finite element analysis.
  • Valve cavity pressure self-balancing structure: compensate for external water pressure changes (pressure fluctuation ≤±5%) through pre-set nitrogen accumulator.
• ​​Anti-methane hydrate​​:
  • The valve housing is electrically heated (power density ≥ 10 W/cm²) to maintain a surface temperature ≥ 20°C (to prevent hydrate crystallization and blockage).
  • Sealant injection channel: Methanol-based inhibitor can be injected in emergency situations.

​​Key Parameters​​

​​Test verification​​

• Pressure cycle test​​: simulate 5,000 water depth pressure fluctuations (0~690 bar), leakage rate ≤API 598 B grade.
• ​​ROV operation verification​​: The manipulator repeated the operation 500 times, and the positioning accuracy error was ≤±1.5mm.

​​API 17D: Subsea Christmas Tree Valves​​

​​Core technical requirements​​
The subsea Christmas tree is the core of the underwater production system, and its valve design must meet the following requirements:

• Ultra-high pressure tolerance:
  • 15,000 psi (1034 bar) grade valves are forged (forging ratio ≥ 4:1) with a grain size of ASTM Grade 7 or above.
  • The valve stem and valve seat are nitrided (surface hardness ≥60 HRC, nitriding layer depth ≥0.3mm).
• ​​Redundant sealing system​​:
  • ​​Main seal​​: Metal to metal seal (API 6A PR2 grade).
  • ​​Emergency seal​​: Injection polymer seal (temperature resistance ≥150℃, response time ≤15 minutes).

​​Material Selection Guide​​

​​Typical case: North Sea oil field project​​

• Depth: 2,800 meters
• ​​Valve Configuration​​:
  • Main production valve: API 17D 10,000 psi rating with dual redundant ROV interfaces.
  • Annular safety valve: Passed API 6FA fire test and can withstand 5,000 opening and closing cycles after burning.
• Operational data:
  • Maintenance-free period: 5 years (2 years for similar valves on land).
  • Failure rate: ≤0.1 times/thousand hours (industry average 0.5 times/thousand hours).

​​API 17TR8: Deepwater valve test method​​

​​Full life cycle verification system​​
This technical report specifies the extreme testing procedures for deep sea valves:

1. ​​Pressure-Temperature Cycle Test​​:

• Alternately apply 690 bar water pressure (simulating 5,000 meters water depth) and 121°C high temperature fluid shock, and cycle 3,000 times.

1. ​​Accelerated Corrosion Test​​:

• Immersed in saline water (Cl⁻ concentration 200,000 ppm) containing H₂S (4%) and CO₂ (10%) for 720 hours.

1. Dynamic load test:

• Simulate the impact of seabed currents (frequency 0.1~5Hz) and apply alternating stress (amplitude ±50 MPa).

Acceptance Criteria

​​Deep-sea technology standards comparison​​

7. Drive and control

API 6DX: Valve Actuator Specification

​​Core Requirements​​
As the core standard for valve automation control, API 6DX places strict performance requirements on actuators:

• ​​Torque output verification​​:
  The actuator must maintain a torque output accuracy of ≤±5% within the load range of 0%~100% and pass 2000 full-load opening and closing cycle tests (allowable torque attenuation ≤3%).
• ​​Extreme Environment Protection​​:
  • ​​IP68 rating: No leakage after 72 hours of continuous operation at 3,000 meters underwater (test pressure ≥ 690 bar).
  • ​​Explosion-proof certification​​: Meets ATEX/IECEx Zone 1 standards (hydrogen environment requires Ex d IIC T4 level).
• ​​Intelligent control interface​​:
  Supports OPC UA protocol, can transmit torque curve, temperature, vibration and other data in real time, and seamlessly connect with DCS system.

​​Key technological breakthroughs​​

​​Application Cases​​

• Arctic LNG Project​​: In an environment of -60℃, the electro-hydraulic actuator is equipped with a self-heating system (power 2kW), and the start-up time is ≤5 minutes.
• ​​Deep-sea Christmas tree​​: ROV detachable hydraulic drive head, underwater plug-in interface life ≥ 500 times.

​​API 11V6: Gas Lift Valve System Design​​

• ​​Gas lift technology optimization​​
  The gas lift valve reduces the density of wellbore fluid by injecting gas. API 11V6 proposes innovative designs for efficient gas injection:
• ​​Nitrogen Chamber Dynamic Compensation​​:
  The bellows pressure balance structure is adopted, and the gas injection pressure fluctuation is ≤±2.5% (the traditional spring type fluctuation is up to ±10%).
• Multi-stage throttling aperture:
  The three-stage pressure-reducing orifice design (aperture ratio 1:2:4) reduces the air flow velocity from supersonic to subsonic (to avoid cavitation damage).
• ​​Sand Erosion Protection​​:
  The flow channel is lined with tungsten carbide (HV ≥ 1200), which can withstand media with sand content ≤ 15% (sand particle size ≤ 500μm).

​​Performance comparison (vs traditional gas lift valve)​​

​​Typical Applications​​

• Shale gas well: daily gas injection volume 500,000 m³, bottom hole pressure fluctuation ≤5%.
• ​​High sulfur oil fields​​: The valve body material is Inconel 625 (PREN ≥ 45), which has passed the NACE TM0177 test.

​​API 682: Specification for Mechanical Seal Systems​​

​​Zero leakage sealing technology​​
In response to the leakage of high-risk media, API 682 proposes a graded sealing solution:

• ​​Double sealing system​​:
  • Plan 53A: External isolation fluid circulation system (pressure 3-5 bar higher than the medium).
  • Plan 74: Double seal + gas barrier (helium leakage rate ≤ 1 ppm).
• ​​Online monitoring​​:
  Real-time monitoring of sealing chamber temperature (±1°C), vibration (0.1~10kHz), and leakage (accuracy 0.1 μL/h).

​​Material Selection Guide​​

​​Industry Benefits​​

• ​​Refinery Hydrogenation Unit​​: Extended seal life from 6 months to 5 years, reducing downtime losses by $1.2 million/year.
• ​​Chemical Plants​​: Reduce VOC leaks by 99%, meeting EPA Leak Detection and Repair (LDAR) requirements.

8. ​​Maintenance and life management​​

API 6DR: Valve Repair Guidelines

​​Core Requirements​​
As the world’s first special standard for valve repair, API 6DR puts forward technical requirements for full-process repair:

• ​​Welding repair process certification​​:
  • AWS D1.1 standard is used for welder qualification certification, and nickel-based alloy (such as Inconel 625) repair needs to pass ASME IX volume assessment.
  • Post-weld heat treatment (PWHT): Select the temperature curve according to the parent material (e.g. carbon steel valve body requires tempering at 595°C × 1h).
• ​​Remaining Life Assessment (RBI):
  • Based on wall thickness measurement (UT inspection) + stress analysis (FEA), calculate the remaining life (formula): L_{rem} = \frac{t_{min} – t_{actual}}{C \cdot R_{corr}}} Where, C is the safety factor (≥2.0), Rcorr is the annual corrosion rate (mm/year).

​​Repair process comparison​​

​​Application Cases​​

• ​​A refinery in the Middle East: Repaired Class 600 gate valve (DN300), cost reduction of 65%, remaining life estimated at 8 years (initial new valve life of 12 years).
• ​​Economic benefits​​: The repair cycle only takes 3 weeks (the new valve procurement cycle is 16 weeks), reducing production losses by $1.8 million.

​​API 589: Valve Fire Damage Assessment Method​

​​Post-fire Assessment Process​​

1. Initial screening:

• Surface temperature record: infer the peak temperature based on the burning traces (for example: the valve body turns blue ≈ 350℃~400℃).
• Hardness gradient test: Measure the hardness (HV) every 2 mm from the surface to the inside. If the attenuation is ≤20%, the substrate value is safe.

1. Metallographic analysis:

• Grain size test: According to ASTM E112 standard, grain growth exceeding level 2 is considered failure (e.g. 20# steel from level 5 to level 3).
• Carbide precipitation: Analyze the distribution of Cr/Mo carbides by SEM-EDS (parts need to be replaced if the concentration is ≥50%).

1. ​​Seal surface scanning​​:

• 3D white light interferometer is used to detect flatness (Ra≤0.8μm). If the ablation depth is ≥0.2mm, re-surfacing is required.

​​Material Recovery Program​​

​​API 20E: Digital Twins and Predictive Maintenance​​

​​Full life cycle data management​​

• Data collection:
  • Manufacturing stage: record material batches, heat treatment curves, non-destructive testing reports (RT/UT).
  • Operation and maintenance stage: real-time upload of vibration (0~10kHz), temperature (-196℃~650℃), and leakage (ppm level).
• ​​AI prediction model​​:
  • Seal life prediction: Based on LSTM algorithm, input temperature fluctuation and opening and closing frequency, error ≤7%.
  • Root cause analysis: Correlate multi-dimensional data (such as vibration spectrum + medium composition) to identify the dominant factors of jamming/corrosion.

​​Blockchain Technology Applications​​

• ​​Unalterable records​​:
  Each repair generates an independent block, which includes the operator ID, the batch of replaced parts, and the hash value of the inspection report.
• ​​Supply Chain Traceability​​:
  Traceability of repair welding materials (such as ERNiCrMo-3) back to the original manufacturer’s certificate ensures material compliance.

​​Implementation Benefits​​

More API standard chapters (1-4): “Full analysis of API valve core standards: 11 major technical systems (1)”

1. ​​General design and manufacturing​​ ​​2. ​​Performance testing and certification​​​​ 3. ​​Wellhead and special applications​​​​4. ​​Quality management system​​​​

More chapters 9-11: “Full analysis of API valve core standards: 11 major technical systems (3)”

9. ​​Special media handling​​10. ​​Structural supplementary standards​​ 11. ​​Storage and transportation supporting standards​​

API standards are the passport to the international market. As an API fully certified manufacturer, JH Valve has a complete system that covers the entire life cycle management of oil and gas industrial valves from design, manufacturing to decommissioning, meeting the technical needs of land, sea and extreme environments. It has been focusing on the oil and gas field for 20 years, with API 6D ball valves and API 600 gate valves as the core. The sealing accuracy reaches 1/10 of the D-level standard and the service life is extended by 60%. From land Class 1500 to deep-sea API 17D, we use API 20E digital traceability to help customers pass the stringent audits in the Middle East and North America. Choosing JH Valve is not only about API compliant products, but also about engineering strength that exceeds standards.

Define competitiveness with API standards – JH Valve helps you break through globally.

9. ​​Special media handling​​

API 622: Specification for Design of Valves for Sour Service

​​Core Requirements​​
For corrosive media such as high sulfur content (H₂S) and carbon dioxide (CO₂), API 622 proposes the following key technical requirements:

• Material crack resistance:
  • Materials that are resistant to sulfide stress cracking (SSC) according to NACE TM0177 include:
    • Duplex steel 2205 (PREN ≥ 40)
    • Nickel-based alloy Inconel 625 (PREN ≥ 50)
  • Hardness control: Valve stem surface hardness ≤22 HRC (to prevent hydrogen embrittlement).
• Sealing system enhancement:
  • Bellows sealing structure (eliminating valve stem leakage), bellows layer number ≥ 8 layers, life ≥ 5000 opening and closing times.
  • The valve seat adopts tungsten carbide metal seal (HV≥1200) and can withstand H2S partial pressure ≥10 bar.

​​Test verification​​

Industry Cases

• ​​Middle East sour gas field​​: After adopting API 622 valves, H₂S leakage accidents were reduced by 98% and the maintenance cycle was extended from 6 months to 5 years.
• ​​Economic Benefits​​: The life cycle cost of a single sour gas well valve was reduced by $2.2 million.

​​API 6S: Technical Specifications for Slurry Valves​​

​​Wear-resistant design technology​​
API 6S proposes innovative solutions for solid particle-containing media such as oil sands and coal slurry:

• Flow channel hardening treatment​​:
  • The inner cavity is welded with chromium carbide (Cr3C2, HV≥800), and the wear-resistant layer thickness is ≥3mm.

Streamlined flow channel design (radius of curvature ≥ 2×DN) reduces the particle impact angle to ≤ 15°.

• ​​Anti-clogging structure​​:
  • A flushing interface is set on the back of the valve seat, which can be injected with high-pressure water (pressure ≥ PN×1.2) to remove sediment.
  • The edge of the valve plate is rounded (R ≥ 5mm) to prevent particles from getting stuck.

​​Performance Parameter Comparison​​

​​Application scenarios​​

• ​​Canadian Oil Sands Project​​: DN400 slurry ball valve has been in operation for 5 years, processing a total of 120 million tons of oil sands, with wear ≤0.5mm.
• ​​Coal chemical black water valve​​: Tolerant coal powder particle size ≤6mm, medium flow rate ≤3m/s.

​​API 591: Sulfur Recovery Unit Valves Standard​​

​​High temperature sulfur corrosion protection​​
In view of the extreme working conditions of the sulfur recovery unit (SRU), API 591 adds the following requirements:

• ​​Material resistant to high temperature corrosion​​:
  • The valve body is made of 310MoLN austenitic steel (silicon content ≤1.5%) and can withstand liquid sulfur corrosion at ≤600℃.
  • The valve stem is made of Incoloy 825 (Ni ≥ 38%), which is resistant to sulfuric acid dew point corrosion.
• Thermal expansion compensation:
  • A flexible graphite expansion joint is installed between the valve cover and the valve body, with a compensation amount of ≥5mm (ΔT=500℃).
  • The valve stem guide sleeve is made of self-lubricating silicon carbide (friction coefficient ≤ 0.1).

​​Key Tests​​

10. ​​Structural Supplementary Standards​​

API 608: Supplementary Specification for Metal Sealed Ball Valves

​​Core structure requirements​​
In response to the special needs of high temperature resistance and corrosion resistance, API 608 puts forward special technical requirements based on general ball valves:

• ​​Blow-out proof valve stem design​​:
  • An inverted sealing structure is set at the bottom of the valve stem (can withstand 1.5×PN pressure in emergency).
  • Valve stem diameter calculation method: Where F is the medium thrust, S allowable is the allowable stress of the material (such as 80 MPa for 316L stainless steel).

• ​​Full metal sealing system​​:
  • Seat and ball matching materials:

​​Comparison with ISO 17292​​

​​API 623: Supplementary Specification for Steel Globe Valves​​

​​Innovative structural design​​
To optimize the performance of globe valves under high pressure differential conditions, API 623 requires:

• ​​Water hammer resistant flow channel​​:
  • S-curve design of flow channel, pressure drop coefficient  Kv​≥0.7 , reduce the risk of sudden changes in flow rate.
  • A balancing hole (diameter ≈ 0.1×DN) is added on the back of the valve disc to balance the upper and lower pressures of the valve disc.
• Bellows Seal Options:
  • The number of bellows layers is ≥6, and the expansion compensation is ≥8mm (to adapt to temperature fluctuations of ±200℃).
  • Fatigue life test: Leakage ≤100 ppm after 10,000 opening and closing cycles.

​​Performance Advantage Comparison​​

API 609: Supplementary Specification for Butterfly Valves

​​Eccentric structure design​​
In response to the flow regulation needs, API 609 puts forward technical requirements for precision butterfly valves:

• ​​Triple eccentric geometry​​:
  • First eccentricity​​: The valve plate axis deviates from the center of the pipeline ( e1​≥0.05× DN ).
  • ​​Second eccentricity​​: The axis of the valve plate sealing surface is tilted (angle ≈8°~12°).
  • ​​Third eccentricity​​: The sealing surface adopts a logarithmic spiral line to achieve zero friction opening and closing.
• Fire protection design:
  • Metal valve seat + graphite sealing ring double insurance, leakage rate ≤D level after passing API 6FA test.

​​Typical Application Parameters​​

11. ​​Storage and transportation supporting standards​​

API 2000: Storage Tank Venting Systems

​​Core Features​​
Design benchmarks for tank breathing valves and emergency relief devices to address oil and gas volatilization and overpressure risks:

• ​​Breathing valve parameters​​:
  • Set pressure: atmospheric pressure tank (±0.5 kPa), pressure tank (±35 kPa).
  • Ventilation calculation: Based on the medium evaporation rate (formula): Where A is the ventilation area (m²), ΔP is the pressure difference (Pa), and ρ is the medium density (kg/m³).

• ​​Flame arrester integration​​:
  Comply with API 2218 standard, the spacing between fire-retardant corrugated plates is ≤0.5mm, and the burning time is ≥2 hours.

​​Technology comparison (vs ISO 28300)​​

​​Industry Applications​​

• Strategic Petroleum Reserve: DN500 breathing valve ventilation volume ≥10,000 m³/h, fire retardant efficiency ≥99%.
• LNG storage tank: -162℃ cryogenic breathing valve, the valve seat material is PTFE composite graphite.

​​API 2610: Storage and transportation terminal loading and unloading systems​​

​​Key technologies of loading and unloading arms​​

• ​​3D Motion Compensation​​:
  • Fully swivel joint design (rotation angle ±15°) to compensate for vessel drift of ±5 meters.
  • Emergency release system (ERS): response time ≤ 3 seconds, residual volume ≤ 0.1%.
• Flow Control:
  • The loading and unloading arm has a diameter of DN150~DN600, and a design flow rate of ≤5 m/s (to prevent static electricity accumulation).
  • Equipped with API 609 triple eccentric butterfly valve, Kv value ≥ 0.85.

​​Safety Protection​​

​​Typical Cases​​

• Qingdao Crude Oil Terminal: 8 DN400 loading and unloading arms, each with a flow rate of 6,000 m³/h, equipped with ERS system to reduce oil spill risk by 95%.

API 2350: Tank Overfill Protection

​​Layered protection system​​

1. ​​First level monitoring​​:

• Radar level meter (accuracy ±0.5mm) + servo level meter redundancy calibration.

1. Secondary alarm:

• The high liquid level interlock (≥95% storage capacity) triggers the pump valve to shut down.

1. ​​Three levels of protection​​:

• The overflow tank capacity is ≥ 10% of the tank volume, and the diversion speed is ≥ 1 m/s.

​​Intelligent Algorithm​​

• Dynamic volume calculation:
  Based on temperature compensation (±50°C) and medium density changes, the liquid level-volume curve is corrected in real time (error ≤ 0.1%).
• ​​Predictive Alerts​​:
  The LSTM model is trained by historical data to warn of overflow risks 15 minutes in advance (accuracy ≥ 92%).

​​Implementation Benefits​​

Typical project application requirements

Middle East LNG project case:

• Pipeline valve: API 6D fully welded ball valve + API 6SS deep sea extension
• Material certification: API 6A PR2 + NACE MR0175
• Quality system: API Q1 + API 20E digital traceability
• Safety requirements: API 14D + API 526 dual protection

More API standard chapters (1-4): “Full analysis of API valve core standards: 11 major technical systems (1)”

1. ​​General design and manufacturing​​ ​​2. ​​Performance testing and certification​​​​ 3. ​​Wellhead and special applications​​​​4. ​​Quality management system​​​​

More API standard chapters (5-8): “Full analysis of API valve core standards: 11 major technical systems (2)”

5. ​​Safety and emergency systems​​6. ​​Subsea and deep sea technology​​ 7. ​​Drive and control​​8. ​​Maintenance and life management​​

API standards are the passport to the international market. As an API fully certified manufacturer, JH Valve has a complete system that covers the entire life cycle management of oil and gas industrial valves from design, manufacturing to decommissioning, meeting the technical needs of land, sea and extreme environments. It has been focusing on the oil and gas field for 20 years, with API 6D ball valves and API 600 gate valves as the core. The sealing accuracy reaches 1/10 of the D-level standard and the service life is extended by 60%. From land Class 1500 to deep-sea API 17D, we use API 20E digital traceability to help customers pass the stringent audits in the Middle East and North America. Choosing JH Valve is not only about API compliant products, but also about engineering strength that exceeds standards.

Define competitiveness with API standards – JH Valve helps you break through globally.