En sistemas de tuberías, el revestimiento de brida 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 y 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, sus funciones, 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

• Clasificaciones de presión: Clase 150 a clase 2500

• Common in small- to medium-diameter piping systems

ASME B16.47

• Covers large-diameter steel flanges de NPS 26 a NPS 60

• Two series: Serie A (heavier, for high-pressure applications) y Serie B (encendedor, rentable, derived from MSS SP-44)

• Clasificaciones de presión: Clase 75 a clase 900

Juntos, these two standards cover nearly the entire range of industrial flanges used in oil and gas, procesamiento químico, generación de energía, tratamiento de agua, e ingenieria marina.

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What is Flange Facing?

El revestimiento de brida 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, temperatura, y tipo de fluido.

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

1. cara levantada (RF)

• 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 a 2500

Aplicaciones: Oil refineries, plantas quimicas, water treatment systems

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2. Cara plana (FF)

• Entire face of the flange is flat

• Usually used with cast iron and fiberglass piping

• Designed for low-pressure, non-critical applications

Aplicaciones: Water distribution, conexiones de la bomba, tuberías de baja presión

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3. Junta tipo anillo (RTJ)

• A machined groove accommodates a metallic ring gasket

• Provides metal-to-metal seal

• Withstands very high pressure and temperature

• Available in Classes 600 y arriba

Aplicaciones: Offshore drilling, petroquímico, high-pressure gas systems

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4. Lengua y ranura (t&GRAMO)

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

• Prevents gasket displacement during installation

• Provides excellent alignment

Aplicaciones: Intercambiadores de calor, reactores químicos, custom piping assemblies

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5. Masculino y Femenino (METRO&F)

• Similar a T.&G but with flat mating surfaces

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

• Ensures accurate gasket positioning

Aplicaciones: Specialty piping, aeroespacial, y sistemas químicos

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Requisitos de acabado superficial

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

• Acabado original: Más común, concentric or spiral serrated finish (Ra 125–500 µin)

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

• Acabado en agua fría: Extremely smooth finish for special soft gaskets (Ra ≤ 63 µin)

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

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Key Considerations for Selecting Flange Facing

1. Presión y temperatura de funcionamiento

• Para alta presión, alta temperatura applications → RTJ is recommended

• Para low-pressure, ambient conditions → FF or RF may be sufficient

2. Tipo de junta

• Juntas blandas (goma, PTFE): Require smooth finishes

• Metallic gaskets (herida en espiral, RTJ): 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

• RTJ, t&GRAMO, and M&F are more expensive but necessary for critical service

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Applications of B16.5 and B16.47 Flange Facing

Industria del petróleo y el gas

• RTJ flanges for offshore rigs, tuberías submarinas, and refineries

• RF flanges for midstream and downstream processing

Química y Petroquímica

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

• Corrosion-resistant alloys required for aggressive chemicals

Generación de energía

• 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

Marina y construcción naval

• 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 prevención de fugas. Poorly selected or incorrectly finished facings lead to gasket failure, falta del tiempo, y reparaciones costosas. Engineers must evaluate the material de la junta, bolt torque, and pressure-temperature rating when specifying flange facings.

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Conclusión

Flange facing is a critical element of ASME B16.5 and B16.47 flanges, ensuring reliable sealing and safe operation in diverse industries. cara levantada is the most commonly used, Cara plana is preferred for low-pressure systems, y Junta tipo anillo is indispensable for high-pressure, aplicaciones de alta temperatura. Other facings such as Lengua & Ranura y Male & Female are used in specialized systems requiring precision alignment.

For industries seeking reliable, high-quality flange solutions, Sasaflange ofertas ASME B16.5 and B16.47 flanges with precise facings tailored to specific applications. With strict adherence to global standards and advanced manufacturing technology, Sasaflange ensures long-term safety, actuación, 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.