Spectacle Blind Flange/Figure 8 flange

Spectacle Blind Flange (Figure 8 Blind) Manufacturer

Spectacle blind flanges provide a practical solution for positive pipeline isolation during maintenance and process changes. JS FITTINGS supplies industrial steel flanges and pipe fittings for distributors, stockists and project buyers, with product specifications confirmed according to applicable standards and customer requirements.

Size & Dimensions: Standard or drawing-based requirements

Pressure Class : Specified for each order

Technical Requirements: Standards and inspection documents as agreed

Get a Free Quote

JS FITTINGS supplies spectacle blind flanges(Figure 8 Blind flanges) for industrial piping systems that require reliable line isolation during maintenance, inspection or process changes. Available configurations are confirmed according to the applicable standard, pressure class, material and project requirements.

Need a quotation? Send us your size, pressure class, material grade and quantity. If you have a technical drawing, please include it for review.

Emails us | Contact Us via WhatsApp

Spectacle Blind Flange Specifications

Item	Specification
Product Type	Spectacle Blind Flange / Figure 8 Blind
Applicable Standards	ASME B16.48 and other standards subject to confirmation
Size Range	Published range: 1/2″–96″, subject to standard and design
Pressure Rating	ASME Class 150–2500 and applicable PN ratings, subject to confirmation
Facing Types	Raised Face (RF), Flat Face (FF) and Ring Type Joint (RTJ), as specified
Materials	Carbon steel, stainless steel and alloy steel, subject to grade availability
Surface Treatment	Anti-rust oil, painting or other agreed treatments, subject to requirements

Final dimensions, pressure ratings, material grades and facing details must be confirmed against the applicable specification and mating flange requirements.

What Is a Spectacle Blind Flange?

A spectacle blind flange, also called a Figure 8 blind, consists of a solid blind plate and an open spacer connected by a web. It is installed between pipe flanges and can be repositioned to either block the line or allow flow through the spacer.

Unlike a standard blind flange, which closes a pipe end, a spectacle blind allows operators to change the line configuration without replacing the entire component.

Spectacle Blind Flange Facing Types

Raised Face (RF)

A raised sealing face used with a compatible gasket. The facing and dimensions must match the mating flanges.

Flat Face (FF)

A flat sealing face designed for compatible flat-face flange connections and gaskets.

Ring Type Joint (RTJ)

A machined ring groove designed for use with a compatible metallic ring gasket in applications requiring an RTJ connection.

Please specify the required facing type when requesting a quotation.

Face types of spectacle blind flange

Applications

Spectacle blind flanges are commonly used in:

Oil and gas pipelines
Petrochemical and chemical processing plants
Power generation facilities
Industrial process piping
Pipeline maintenance and equipment isolation

Correct selection depends on the operating conditions, piping design, pressure class and applicable safety procedures.

Spectacle blind flange on a pipeline

Manufacturing and Quality Requirements

As an industrial pipe fitting and flange manufacturer established in 1983, JS FITTINGS supplies products for distributors, stockists, trading companies and engineering projects.

For spectacle blind flange orders, we recommend confirming the following before production:

Applicable standard and nominal size
Pressure class and facing type
Material grade and required documentation
Dimensional and inspection requirements
Surface treatment, marking and export packing

Inspection documents and third-party inspection arrangements can be discussed according to the order requirements.

How to Request a Quotation

To help us review your requirements and prepare an accurate quotation, please provide:

Size and pressure class
Material grade and facing type
Applicable standard or technical drawing
Required quantity
Destination country and any special inspection requirements

Not sure which specification you need? Send us your drawing or project requirements, and our team can review the details with you.

Why Choose JS FITTINGs as your Flanges Supplier?

Cangzhou-Based Manufacturing Hub
30,000㎡ production facility
5,000+ ton annual capacity
Same-day shipping for standard sizes
ISO 9001, CE, API 6A certified
100% PMI tested material chemistry

Flange factory

Spectacle blind flanges

Frequently Asked Questions

What information do you need to quote a spectacle blind flange?

Please provide the size, pressure class, material grade, facing type, quantity and applicable standard. A drawing is helpful for non-standard requirements.

Can you supply spectacle blind flanges according to customer drawings?

Send us your drawing and technical requirements for review. Manufacturing feasibility and the applicable specifications will be confirmed before quotation.

Can you provide material certificates and inspection documents?

Please state your documentation requirements when requesting a quotation. Available documents and inspection arrangements will be confirmed for your order.

What is the difference between a spectacle blind and a blind flange?

A spectacle blind has both a solid section and an open spacer section connected as one component. A blind flange is a separate solid flange used to close a pipe end or equipment opening.