Size range:
- Size: 1/2” to 60”, DN 12mm to DN 1500mm
- Pressure class: Class 150 to Class 2,500, PN 2.5 to PN 250
- Facing: RF / RTJ
A spectacle flange is a specialty flange made of two metal discs attached in the middle by a small section of steel. Spectable flanges get their name because they look like a pair of reading glasses, or spectacles. Spectacle flanges, also known as spectacle blind flanges, are most commonly used on piping systems that need to be separated regularly or where the flow through the systems is regularly stopped. One end of the spectacle flange is solid, while the other end has a hole in the center. The spectacle flange can be rotated to place either the solid or hollow end within the pipe system, thereby opening or closing the flow.
Advantages of Spectacle Flanges
- Spectacle flanges require no welding for installation
- Spectacle flanges from Sunny Steel Flange have a wide range of pressure tolerances
- Sunny Steel will manufacture spectacle flanges to your specifications
For pipe Flanges-regularly seperated for isolation, maintenance or reasons, a spectacle extrudes Solution. Typically, spec blinds was mounted in the open position so-your flow pipe operates and is normally. Blinds is mounted onto one of the $number so is need to isolate a, it ' s easy!
Dimensions of spectacle blinds according to ASME B16.48
Flange spades and ring spacers, as separate products, are used when the rotation of a spectacle blind would be difficult due to space constraints. ASME B16.48 covers the dimensions and specifications of these isolation devices.
- Spectacle blind
- Flanges
- Gaskets
- Stud bolts
Spectacle blind types
There are three types of spectacle blinds:
Flat face spectacle blind (FF):
similar to a flat face flange, the surface of the disc is flat (suited for flat face gaskets, for low-pressure applications).
Raised face spectacle blind (RF):
likewise raised face flanges, there is an additional thickness on the surface of the disc. This type fits semi-metallic gaskets, as the spiral wound type.
Ring joint face spectacle blind (RTJ):
a groove is inscribed on the surface of the disc. This type is used in conjunction with ring joint gaskets.
Flange spade vs Spectacle blinds
A spectacle blind combines a flange spade and a ring spacer in a single device (this is the reason why flange spades are called “single-blinds” or “blanks”). The difference is that spectacle blinds may need some space to be rotated, and this space is not always available due to the routing of the piping system. This is when two separate devices are used, as they do not require rotation to be installed.
Spades, ring spacers, and spectacle blinds are available in multiple sizes (from 1/2 inch to 24 inches, and pressure rating from 150 to 2500#) and material grades (the same available for standard flanges) depending on the fluid conveyed by the pipeline.
The difference between spades/ring spacers and spectacle blinds is shown in the image:
