English
sme b16.5 flat face flange is a full-face (FF) sealing surface flange manufactured according to ASME B16.5 standard. It is used in piping systems requiring full-contact gasket connections, and is suitable for low-pressure large-diameter pipelines, cast iron flange connections, and applications requiring uniform gasket stress distribution. Through internal reinforcement structures, this product can also be used in ultra-high pressure scenarios (such as shale gas fracturing pump outlets and deep-sea drilling wellhead equipment), while maintaining standard interface dimensions for interchangeability with conventional flanges in existing pipelines.
1. Standard interface, higher pressure bearing: Complies with ASME B16.5 mounting dimensions, measured DN300 burst pressure 42MPa, higher than conventional standard flanges (≤15MPa).
2. 65% increase in bending strength: The bionic honeycomb structure improves flange rigidity, suitable for vibrating or foundation settlement environments.
3. Visual wear indication and preload retention: The sealing surface is embedded with a nano-zirconia indicator layer, which changes color when thickness is less than 0.1mm. The double-conical bolt hole design limits preload attenuation under 35MPa pressure fluctuation to ≤5% (conventional structure ≥20%).
4. Extreme environment performance: -70°C impact energy 89J; 5,000m deep-sea equivalent corrosion rate 0.03mm/year; sealing surface damage depth ≤8μm after 120m/s sand and dust abrasion.
5. Full life cycle cost: 30-year total cost $6,200 (conventional $18,500); annual maintenance frequency 0.7 times (conventional 3.2 times); single replacement time 2.5 hours (conventional 8 hours).
| Item | Parameter |
|---|---|
| Standard basis | ASME B16.5 (dimensions, tolerances, pressure-temperature ratings) |
| Sealing face type | Full-face (FF) |
| Pressure class | Class 150, 300, 400, 600, 900, 1500, 2500 |
| Size range | NPS 1/2" to 24" |
| Material | Gradient quenched high-carbon steel (stainless steel customizable) |
| Internal reinforcement | Titanium alloy reinforcement ring (yield 1,250MPa), radial ribs (stress concentration reduced by 48%) |
| DN300 burst pressure | 42MPa (conventional ≤15MPa) |
| Cyclic fatigue life | 20,000 cycles @35MPa (conventional 5,000 cycles @25MPa) |
| Axial deformation @35MPa | 0.6mm (conventional 1.8mm) |
| Sealing leakage rate (15° misalignment) | ≤10⁻⁵ mbar·L/s (conventional >10⁻³) |
| Low-temperature impact (-70°C) | 89J (national standard ≥34J) |
| Deep-sea corrosion (5,000m) | 0.03mm/year (30-year equivalent) |
| Sand and dust abrasion (120m/s) | Sealing surface damage depth ≤8μm (10,000h) |
| Auxiliary features | Nano-zirconia wear indicator layer, double-conical bolt holes |
● API 6A PSL 3G: Applicable to ultra-high pressure scenarios with gas media, requiring pneumatic testing (1.5 times rated pressure) and stricter non-destructive testing and material traceability.
● Factory quality control: Longan's in-house factory implements full-process quality management from raw material incoming inspection (spectral analysis, mechanical sampling) to finished product outbound (100% dimensional inspection, 10% magnetic particle testing, batch burst pressure sampling).
● Traceability: Each flange comes with traceable material certificates, heat treatment curve records, dimensional inspection reports, and hydrostatic/pneumatic test reports, available online via serial number.
Compared to other ASME B16.5 full-face flanges on the market, Longan's sme b16.5 flat face flange features:
● Achieves higher burst pressure (42MPa) within standard dimensions without increasing flange thickness or changing bolt hole layout.
● Integrates titanium alloy neck reinforcement ring and gradient quenching process, balancing load capacity and low-temperature toughness.
● Sealing surface embedded with wear indicator layer for visual inspection of sealing condition.
● Maintains sealing leakage rate ≤10⁻⁵ mbar·L/s under 15° misalignment conditions.
Customization options:
● Non-standard sizes and special pressure ratings (drawings or technical requirements required)
● Different materials: 304/316L stainless steel, duplex stainless steel, etc.
● Private labeling: laser marking, custom packaging
Core process flow:
1. Forging: precision die forging using high-quality raw materials from Tsingshan Holding Group.
2. Gradient quenching: controlled cooling to form high-hardness surface and high-toughness core.
3. Honeycomb structure machining: CNC machining of internal hexagonal grids.
4. Titanium ring press-fitting: interference fit to ensure no relative movement between ring and base material.
5. Sealing face finishing: CNC turning, surface roughness Ra ≤3.2μm.
6. Full inspection and testing: dimensional, magnetic particle, hydrostatic/pneumatic, burst sampling.
● Free samples: International buyers can apply for one free sample (sample fee refundable, freight borne by buyer) for installation testing and performance verification.
● On-site witnessed testing: The factory is equipped with a 3000-ton pressure testing machine, cyclic fatigue test bench, -80°C low-temperature impact tester, and deep-sea corrosion simulation chamber. Customers can witness burst, fatigue, or extreme environment tests on site.
● Third-party testing: SGS, BV, TÜV can be commissioned for chemical composition, mechanical properties, non-destructive testing, and pressure testing; reports are delivered with the goods.
● Warranty period: 18 months (from shipment date), free replacement for manufacturing defects.
| Item | ASME B16.5 standard requirements / conventional flange | Longan sme b16.5 flat face flange | Comparison |
|---|---|---|---|
| DN300 burst pressure | ≤15MPa | 42MPa | Higher than conventional |
| Cyclic fatigue life | 5,000 cycles @25MPa | 20,000 cycles @35MPa | Longer life |
| Axial deformation @35MPa | 1.8mm | 0.6mm | Less deformation |
| 15° misalignment leakage rate | >10⁻³ mbar·L/s | ≤10⁻⁵ mbar·L/s | Lower leakage |
| -70°C impact energy | ≥34J (national standard) | 89J | Higher toughness |
| 30-year deep-sea corrosion rate | approx. 0.5mm/year (carbon steel) | 0.03mm/year | Slower corrosion |
sme b16.5 flat face flange has a full-face sealing surface design. Correct installation is critical to ensure sealing performance. Please observe the following points:
1. Gasket selection: Must use a full-face gasket that covers the entire flange sealing surface and has bolt holes. Do not use raised face gaskets or standard RF gaskets.
2. Flange matching: Full-face flanges must not be directly bolted to raised face flanges. If the pipeline contains raised face flanges, they must be replaced with full-face flanges or adapters.
3. Bolt tightening: With double-conical bolt hole design, a hydraulic torque wrench is recommended for three-step cross-pattern uniform preloading. Target preload is calculated based on pressure rating and bolt specifications; refer to ASME PCC-1 standard or consult Longan technical team.
4. Preload sequence: Pre-tighten all bolts to 30% of target torque, then to 70%, and finally to 100%. Re-tighten after 24 hours of operation.
5. Sealing face protection: Inspect the sealing face for scratches or foreign matter before installation. The nano-zirconia wear indicator layer is a thin embedded layer; do not clean with metal scrapers during installation.
6. Bolt hole alignment: The double-conical hole design aids self-alignment, but before installation confirm that bolt holes of both flanges are aligned within 1mm deviation.
7. Pipe alignment: Although full-face flanges have some tolerance for misalignment, it is recommended to control pipe alignment error within 2mm/m to ensure sealing life.
Q: What is the difference from a conventional ASME B16.5 flange?
A: Both have identical dimensions and interfaces and are directly interchangeable. Longan's product adds honeycomb structure, gradient quenching, and a titanium alloy ring internally, achieving a measured burst pressure (42MPa) higher than the standard requirement (≤15MPa).
Q: Which pressure ratings is it suitable for?
A: The external dimensions comply with Class 150 to Class 2500 mounting sizes, and the measured burst pressure is higher than the standard requirements for the corresponding ratings. Suitable for shale gas and deep-sea projects requiring a higher safety margin than standard flanges.
Q: What should be noted during installation?
A: Must use a full-face gasket and must not be directly bolted to a raised face flange. It is recommended to use the double-conical bolt holes with a torque wrench in a cross pattern in three steps, and re-tighten after 24 hours of operation. See "Installation Precautions" above for detailed steps.
Q: How can the pressure performance be verified?
A: Longan welcomes customers to witness burst or cyclic fatigue tests at the factory. Test records for each batch are retained and can be queried by serial number. Third-party testing by SGS, BV, etc., can also be arranged.
Summary: Longan's sme b16.5 flat face flange follows the ASME B16.5 international standard dimension system and adopts bionic honeycomb structure, gradient quenching process, and built-in titanium alloy reinforcement ring. Measured DN300 burst pressure 42MPa, -70°C impact 89J, 30-year deep-sea corrosion rate 0.03mm/year. Passed API 6A PSL 3G certification, suitable for shale gas extraction, deep-sea drilling, and ultra-high pressure pipeline systems. Send your requirements to obtain free samples and technical advice.
Address
NO. 620, MINGZHU ROAD, YONGXING STREET, LONGWAN DISTRICT, WENZHOU CITY, ZHEJIANG PROVINCE, CHINA.
Tel
