Guia para flanges de face elevada deslizantes

Flanges são componentes essenciais em sistemas de tubulação, fornecendo um método seguro para conectar tubos, válvulas, bombas, e outros equipamentos. Entre os muitos tipos de flanges disponíveis, o slip-on raised face (SORF) flange is widely specified where its geometry, welded attachment and pressure-temperature rating suit the piping design. Para engenheiros, compradores, e gerentes de projetos, having a clear understanding of this flange type is important for making informed decisions. This article offers a detailed guide to slip-on raised face flanges, including their design, características, aplicações, and benefits.

What Is a Slip-On Raised Face Flange?

A slip-on raised face flange is a type of flange that is slipped over the pipe end before being joined to the pipe with the weld arrangement required by the approved drawing, welding procedure and governing piping code. The raised face (RF) design enhances the sealing surface, concentrating gasket compression and improving leak resistance.

Principais recursos:

The pipe goes through the bore of the flange.
Fillet welds are applied on both sides for secure connection.
Raised face provides a gasket seating area.
Manufactured under standards like ASME B16.5, DIN, EN, JIS, and API.

Advantages of Slip-On Raised Face Flanges

Facilidade de instalação:
They are easier to align and weld compared to weld neck flanges.
Econômico:
Custo inicial mais baixo do que flanges com pescoço soldado, making them suitable for large-scale projects.
Aplicações versáteis:
Available in a wide range of sizes and pressure ratings.
Good Sealing Capability:
A compatible gasket and controlled assembly can provide reliable sealing; the raised face alone does not guarantee a leak-free joint.
Reduced Machining Requirements:
Ao contrário dos flanges de pescoço soldado, they require less precise cutting of pipe lengths.

Padrões e Especificações

ASME B16.5 cobre flanges de tubos e acessórios flangeados da NPS 1/2 através do NPS 24, including pressure-temperature ratings, materiais, dimensões, tolerâncias, marcação, testing and methods of designating openings. The ordered edition and project specification govern.

ASME B16.47 should not be presented as a general large-diameter SORF standard. Its published scope is large-diameter steel welding neck and blind flanges from NPS 26 através do NPS 60. API, EN/DIN and JIS requirements also apply only when the exact flange type, material and project specification call for them; their dimensions and ratings must not be mixed automatically with ASME B16.5.

Slip-On Raised Face Flange Dimensions: What Buyers Should Check

A purchase description should state the standard and edition, NPS, classe de pressão, especificação e grau do material, slip-on type, raised-face designation, pipe OD and schedule or finished bore. Verify flange OD and thickness, dimensões do cubo, chato, diâmetro do círculo do parafuso, bolt-hole quantity and diameter, raised-face diameter and height, and the required facing finish against the applicable drawing or standard table.

There is no single universal “slip-on raised face flange dimensions” table. Dimensions change with NPS, classe e padrão, so the approved drawing should accompany an RFQ whenever interchangeability is critical.

Materials Used in Slip-On Raised Face Flanges

The choice of material depends on the operating environment:

Aço inoxidável (304, 316, 321, 347) – For corrosion resistance in marine and chemical applications.
Aço carbono (A105, A350LF2) – For moderate environments and cost efficiency.
Liga de aço (F11, F22) – For high-temperature and high-pressure services.
Aço Duplex e Super Duplex – For offshore and aggressive environments.
Ligas de Níquel (Inconel, Monel, Hastelloy) – For chemical plants and high-temperature systems.

Common Applications of Slip-On Raised Face Flanges

SORF flanges are used in water, utilidade, químico, marinho, energy and general process piping when the governing design code and project specification permit a slip-on welded joint. The industry name alone does not establish suitability: pressão e temperatura de projeto, cargas cíclicas, tolerância à corrosão, fluid hazards, cronograma de tubulação, qualificação de soldagem, inspection and mating equipment must be reviewed for each service.

De alta pressão, severe cyclic, fatigue-sensitive, lethal-service or nuclear applications require project-specific engineering review and may call for another flange type. A material grade must also be selected from the actual medium, concentração, temperature and fabrication conditions rather than from a broad industry label.

Sealing Performance and Gaskets

A raised-face joint commonly uses a ring gasket located inside the bolt circle. Full-face gaskets are commonly associated with flat-face flanges, especially where flange bending must be limited. Do not confuse a generic metal ring or ring-style gasket with an RTJ metal ring: an RTJ gasket requires the matching ring-joint groove and specified RTJ design.

Gasket selection must match the flange facing, acabamento frontal, fluido, pressão, temperatura, ciclismo, fire-safety or emissions requirements, bolting and assembly procedure. PTFE, grafite, elastomeric, spiral-wound and metallic constructions are not universally interchangeable. Rubber should not be promoted as a default SORF gasket without confirming the service and flange design.

For background, ver Garlock’s full-face gasket guidance e flange-type gasket guidance.

Installation of Slip-On Raised Face Flanges

Confirme a identidade do flange, material, aula, chato, facing and mating component against the approved drawing.
Slide the flange over the pipe and control alignment, pipe insertion and setback so the bore, weld and sealing face remain unobstructed.
Apply the internal and external fillet-weld arrangement required by the approved WPS, drawing and piping code; protect the raised face from weld spatter and handling damage.
Inspect alignment, soldas, bore clearance and face condition to the specified acceptance criteria.
Install the approved gasket and bolting, then tighten using the specified sequence, lubrication and target load.

Reliable service depends on the complete joint design and controlled assembly. The flange type or raised face by itself cannot guarantee leak-free operation.

Slip-On Raised Face vs Other Flange Types

Slip-On vs Pescoço Soldado: a slip-on flange can simplify fit-up and may reduce initial component cost, while a weld-neck flange uses a butt-welded hub transition that is often selected for severe cyclic or higher-load service. The design code and project specification decide suitability—not price alone.
Slip-On vs Solda de Soquete: socket-weld flanges use a socket and are generally associated with smaller-bore piping; their permitted ranges and service restrictions must be checked in the governing standard.
Slip-On vs Blind: a slip-on flange joins to a pipe, while a blind flange closes an opening. They have different functions and are not substitutes.

For a focused face comparison, read Face elevada vs flange de face plana.

Limitations of Slip-On Raised Face Flanges

The pipe-overlap geometry can create a crevice region that requires corrosion and cleaning review for the actual fluid.
Severe cyclic, fatigue-sensitive, high-load or critical services may favor a weld-neck design under the applicable project rules.
Fit-up must control pipe insertion, weld setback and bore clearance while protecting the sealing face.
Escopo da inspeção, NDE and documentation are order-specific; they should be defined before quotation rather than assumed.

Factory-Direct Supply and RFQ Support

SASAFLANGE provides factory-direct supply for common flange types across carbon steel, aço inoxidável, duplex and super duplex stainless steel, nickel alloys and titanium alloys. Standard and commonly sourced specifications can be reviewed against the buyer’s RFQ, while unusual sizes, materiais, tests and documentation remain subject to technical and commercial confirmation.

Our support can cover drawing and specification review, material-grade checks, dimensional and facing requirements, inspection-document coordination, packing and export documentation. This is specification-led quotation support; it does not imply free samples, free services, live stock, fixed lead times or universal certification.

View our Slip-On Raised Face Flanges ou send your flange RFQ.

Conclusão

A slip-on raised face flange combines a pipe attachment type with a gasket-facing type. Correct selection requires the governing standard and edition, NPS, classe de pressão, material, cronograma de furo ou tubulação, detalhes voltados, junta, aparafusamento, welding and inspection requirements to be considered together.

SORF flanges can be a practical choice where the piping design permits them, but they are not automatically interchangeable with weld-neck, flat-face or RTJ arrangements. Send the complete RFQ and mating-flange information so the proposed supply can be checked before order confirmation.

Perguntas frequentes

What is a slip-on raised face flange?

It is a flange that slips over the pipe for welded attachment and has a raised annular gasket seating surface. “Slip-on” describes attachment; “raised face” describes the facing.

What is a slip-on flange used for?

It is used where the piping code and project specification permit a slip-on welded joint. Suitability depends on pressure, temperatura, loads, material, corrosão, welding and inspection requirements.

What are the disadvantages of slip-on flanges?

They require controlled internal and external weld details, can create a crevice region, and may be less suitable than weld-neck flanges for severe cyclic or high-load service.

Why do flanges have a raised face?

The smaller gasket seating area helps develop gasket seating stress from the available bolt load. It does not by itself guarantee leak-tightness.

How can I identify raised face versus flat face?

An RF flange has a visible or measurable annular step around the bore; an FF flange has no raised annular sealing step. Confirm the drawing and marking rather than relying only on appearance.

Can raised-face and flat-face flanges be used together?

Not as an automatic match. The responsible engineer and equipment manufacturer should review flange bending, materiais, gasket or spacer arrangement, bolting and service conditions before approval.