В трубопроводных системах, тот облицовка фланца is a critical feature that determines how two flanges seal together with the help of a gasket. Without proper facing, even the strongest flanges and the best bolts cannot prevent leaks. Two of the most widely recognized standards for flanges are ASME B16.5 и ASME B16.47. While both cover different flange size ranges, their facing types share common design principles and applications.

This article provides a detailed guide on flange facing for B16.5 and B16.47 flanges, explaining the types of facings, their functions, and the key considerations engineers must evaluate when selecting the right flange connection for industrial projects.

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Overview of B16.5 and B16.47 Flanges

ASME B16.5

• Covers flanges and flanged fittings from NPS ½ to NPS 24

• Номинальное давление: Сорт 150 в класс 2500

• Common in small- to medium-diameter piping systems

ASME B16.47

• Covers large-diameter steel flanges от НПС 26 to NPS 60

• Two series: Серия А (heavier, for high-pressure applications) и Серия Б (легче, cost-effective, derived from MSS SP-44)

• Номинальное давление: Сорт 75 в класс 900

Together, these two standards cover nearly the entire range of industrial flanges used in oil and gas, химическая обработка, производство электроэнергии, очистка воды, и морская техника.

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What is Flange Facing?

The облицовка фланца is the finish applied to the surface of the flange that comes into contact with the gasket. Its purpose is to ensure tight sealing, proper load distribution, and gasket retention. Different facing types are specified depending on the application’s pressure, температура, и тип жидкости.

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Common Flange Facing Types for B16.5 and B16.47

1. Поднятое лицо (РФ)

• Most widely used facing type

• A small area around the bore is raised above the bolt circle

• Standard roughness ensures gasket grip

• Used in Classes 150 к 2500

Приложения: Oil refineries, химические заводы, water treatment systems

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2. Плоское Лицо (ФФ)

• Entire face of the flange is flat

• Usually used with cast iron and fiberglass piping

• Designed for low-pressure, non-critical applications

Приложения: Water distribution, соединения насоса, трубопроводы низкого давления

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3. Кольцевое соединение типа (РТЖ)

• A machined groove accommodates a metallic ring gasket

• Provides metal-to-metal seal

• Withstands very high pressure and temperature

• Available in Classes 600 и выше

Приложения: Offshore drilling, нефтехимический, high-pressure gas systems

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4. Язык и паз (Т&Г)

• One flange has a raised tongue, and the other has a matching groove

• Prevents gasket displacement during installation

• Provides excellent alignment

Приложения: Теплообменники, chemical reactors, custom piping assemblies

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5. Мужчина и Женщина (М&Ф)

• Похоже на: Т&G but with flat mating surfaces

• Male flange has a raised portion; female flange has a matching recess

• Ensures accurate gasket positioning

Приложения: Specialty piping, аэрокосмический, and chemical systems

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Surface Finish Requirements

ASME standards specify the surface roughness of flange facings to ensure proper gasket interaction:

• Запасная отделка: Наиболее распространенный, concentric or spiral serrated finish (Ra 125–500 µin)

• Гладкая отделка: For soft gaskets, provides improved contact area (Ra 63–125 µin)

• Отделка холодной водой: Extremely smooth finish for special soft gaskets (Ра ≤ 63 микродюйм)

Key Point: The correct surface finish prevents leakage and extends gasket life.

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Key Considerations for Selecting Flange Facing

1. Рабочее давление и температура

• Для высокое давление, высокотемпературный applications → RTJ is recommended

• Для низкого давления, ambient conditions → FF or RF may be sufficient

2. Тип прокладки

• Мягкие прокладки (резина, ПТФЭ): Require smooth finishes

• Metallic gaskets (спиральная рана, РТЖ): Require serrated or grooved facings

3. Piping Material Compatibility

• Cast iron and non-metallic pipes → Use Flat Face

• Steel and alloy pipelines → Use Raised Face or RTJ

4. Maintenance and Accessibility

• RF and FF flanges are easier to assemble and maintain

• RTJ flanges require precise machining and ring gasket handling

5. Cost and Availability

• RF and FF are cost-effective and widely available

• РТЖ, Т&Г, and M&F are more expensive but necessary for critical service

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Applications of B16.5 and B16.47 Flange Facing

Нефтяная и газовая промышленность

• RTJ flanges for offshore rigs, subsea pipelines, и нефтеперерабатывающие заводы

• RF flanges for midstream and downstream processing

Химическая и нефтехимическая промышленность

• RF and T&G flanges in reactors and distillation units

• Corrosion-resistant alloys required for aggressive chemicals

Производство электроэнергии

• RTJ flanges for high-pressure steam lines

• RF flanges for cooling water systems

Water Treatment and Distribution

• FF flanges for low-pressure water pipelines

• RF flanges for desalination and wastewater plants

Морское и судостроение

• Stainless steel RF flanges for seawater cooling

• RTJ flanges for marine exhaust and fuel systems

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Flange Facing and Leak Prevention

The correct flange facing directly influences предотвращение утечек. Poorly selected or incorrectly finished facings lead to gasket failure, время простоя, and costly repairs. Engineers must evaluate the материал прокладки, bolt torque, and pressure-temperature rating when specifying flange facings.

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Заключение

Flange facing is a critical element of ASME B16.5 and B16.47 flanges, ensuring reliable sealing and safe operation in diverse industries. Поднятое лицо is the most commonly used, Плоское Лицо is preferred for low-pressure systems, и Кольцевое соединение типа is indispensable for high-pressure, высокотемпературные применения. Other facings such as Язык & Канавка и Мужской & Женский are used in specialized systems requiring precision alignment.

For industries seeking reliable, high-quality flange solutions, Сасафланж предложения ASME B16.5 and B16.47 flanges with precise facings tailored to specific applications. With strict adherence to global standards and advanced manufacturing technology, Сасафланж ensures long-term safety, производительность, and efficiency in piping systems worldwide.

By carefully considering flange facing types, engineers and buyers can optimize system integrity, reduce leakage risks, and extend the service life of critical piping components.