Spectacle Blinds / Figure-8 Blinds
Get Figure-8 blind flanges from the specialists in spectacle blinds.
SPECTACLE BLIND FEATURES & SPECIFICATIONS:
- Available in Line Sizes: 1/2" to 96"
- Pressure Rating Classes: 150#, 300#, 600#, 900#, 1500#, 2500#
- Stocked in 516 - Gr70 carbon steel and 304/316 stainless steels; can supply any alloy
- Finish options: Serrated (125 / 250 RMS) or Mill
- Face options: Flat Face, Raised Face, Octagonal, or Ring Type Joint (RTJ)
- Each spec blind is stamped with the line size and flange rating, and features smooth grounded edges
- Meets ASME standards: B16.48 • B16.5 • B16.20 • B16.47 (For larger diameters)
- In-stock orders ship within 24 hours, and same day local delivery available in Texas and Louisiana.
For custom requirements, USA Industries offers tailored solutions under our ISO 9001:2015 quality-assurance program.
Spectacle Blind 3D Product Rotation
Spectacle blinds, alternatively known as spectacle flanges and figure-8 blinds, comprise two metal discs connected by a handle, resembling a pair of spectacles. While one disc is solid, the other features a hole or opening, enabling flow through the system when aligned with the pipe or vessel. We manufacture our figure-8 blinds from single machined metal pieces, eliminating the need for separate paddle blinds and spacers during pipe maintenance isolation.
PRIMARY USE FOR A SPECTACLE BLIND:
By rotating the handle to align the solid disc with the pipeline, operators can effectively shut off the flow of fluids or gases through the isolated section. This enables maintenance activities to be performed on downstream equipment without the need to shut down the entire system, minimizing downtime and operational disruptions.
OTHER USES FOR A SPECTACLE BLIND:
Spectacle blinds serve the purpose of pressure testing pipelines, valves, and other pressure-containing components to verify their structural integrity and leak-tightness. Operators align the solid disc with the pipeline during hydrostatic or pneumatic testing procedures to create a temporary seal, allowing pressure to build up within the system. This procedure enables the detection of any leaks, weaknesses, or defects in the pipeline or its components.
Operators employ spectacle blinds to regulate flow within piping systems by partially or fully obstructing the flow path. They control the flow rate or divert flow to alternative routes by adjusting the position of the handle, providing flexibility in managing fluid handling processes.
Pipe Schedule Chart Link
Blind Thickness Chart Link
Carbon vs. Stainless Link
Frequently Asked Spectacle Blind Questions
Yes. We refer to this as a blind spacer set. We typically manufacture this configuration on larger sizes.
Yes. We will make these in any alloy that you require, and is available.
Let us know what ID you need and we will manufacture them to the specification you provide to us.
Tell us the thickness you need and we will manufacutre it to that specification.
On small spec blinds the web typically fits between the bolt holes. On larger spec blinds it's common to drill a hole in the center of the web for a bolt to fit through which holds the blind in place. If you want the tie-bar to be made differently, let us know.
Mill finishes or machined 125-250 RMS finishes are the most common finishes we produce, but we can finish them however you like. Additionally, RTJ (RJ) gasket surfaces can be provided in oval or octagonal form.
Yes. Let us know how you want the additional thickness machined down from the outside diameter to the raised face gasket area. This is not common and will require an additional fee.
Yes. First, we need to know if you prefer an RTJ (RJ) male or RTJ (RJ) female spectacle blind.
For a male RTJ blind, the gasket profile is machined onto the blind, but this isn't usually preferred because any damage to the gasket profile will render it unusable. For a female RTJ blind, the area for the gasket seating profile is machined into the blind. This is preferred because commonly available gaskets can be used between the blind and flange.
We also need to know the profile you'd like on your gasket surface.
For male RTJ blinds, the options are oval or octagonal. Female RTJ blinds are typically requested as octagonal, which has 3 sides on each mating area (like a flat bottom V).
We can accommodate whatever combination you require for your blinds!
Yes. We will manufacture your blind(s) with any additional feature you need.
Yes, carbon or carbon alloy steel spectacle blinds will be color coded in the webbing of the blind.
150#: Red
300#: Blue
600#: Yellow
900#: Green
1500#: White
2500#: Orange