This reference provides the dimensional and installation-related information for a Blind Flange 20 Inch Class 600. Use the source data below when checking flange thickness, weight, stud bolt requirements, bolt quantity, and hole diameter for drafting or piping coordination.
Because flange selection depends on the complete piping specification, treat this page as a dimensional reference rather than a substitute for project engineering review. Confirm the applicable material, gasket, bolting, and pressure-temperature requirements before fabrication or installation.
Blind Flange 20″ Class 600
Blind Flange 20″ Class 600 is used to seal the end of a piping system or close off a flange connection in Class 600 service. It is a solid flange without a center bore and is commonly used in industrial piping systems, maintenance isolation points, and future pipeline expansion connections where a higher pressure rating is required.
This dimension data is based on ANSI / ASME B16.5-2020.
Blind Flange 20″ Class 600 Dimensions
- Reference Standard: ANSI / ASME B16.5
- Nominal Pipe Size (NPS): 20″
- DN Size: DN500
- Flange Thickness: 88.9mm
- Weight: 368kg
- Stud Bolt Size: 1 5/8″ UNC (or M42) x 285 Long
- Number of Bolts: 24
- Hole Diameter: 1 3/4″ (44.45mm)
What Is a Blind Flange?
A blind flange is a blank flange used to close the end of a pipeline, vessel nozzle, or equipment connection. It provides a secure shutoff point and is often selected when future maintenance, inspection, or line extension may be required.
Common Applications
Blind Flange 20″ Class 600 is commonly used for:
- Pipe end closure
- Equipment isolation
- Valve and nozzle blanking
- Maintenance shutdown work
- Process and utility piping systems
- Higher pressure piping applications
CAD Drawing Download
This page includes the CAD drawing file for Blind Flange 20″ Class 600, which can be used for drafting, detailing, and piping layout coordination.
Available Blind Flange Class 600 Sizes
This size is part of the Blind Flange Class 600 series. Check other sizes in the same category to find matching dimension data and CAD files for your project.
Notes
Before fabrication or installation, always confirm the latest project requirements, flange material specification, gasket type, bolt length, and applicable pressure-temperature rating.
How to Use This Blind Flange Reference
A blind flange has no center opening, so it closes a flanged pipe, vessel nozzle, valve connection, or equipment outlet. Unlike a flange intended to pass fluid, its primary function is isolation and closure. It can also provide a removable access point when a line may require inspection, maintenance, or future extension.
Important Details in the Source Data
- Nominal size: Use the NPS and DN designations together when comparing drawings, purchase documents, and piping specifications.
- Thickness and weight: These values help with layout coordination, handling planning, support checks, and equipment interface reviews. They do not replace a project-specific structural or lifting assessment.
- Stud bolts and bolt count: Confirm that the listed bolting arrangement matches the mating flange, gasket selection, material requirements, and approved project specification.
- Hole diameter: Check bolt-hole clearance against the mating flange and the actual bolting hardware before detailing or procurement.
Connections to Related Pipe References
For a broader design workflow, compare this page with the site’s flange dimensions, pipe schedules, flange bolt sizing, gasket references, and piping terminology resources. These related references can help coordinate the blind flange with the adjoining pipe and equipment connection without treating any single dimension as a complete design approval.
CAD and Drawing Coordination
The downloadable DWG is intended for drafting, detailing, and piping layout coordination. Before issuing a drawing, verify the mating flange, gasket seating arrangement, bolt access, insulation or clearance requirements, and the project’s latest approved specifications. The CAD file should be checked against the authoritative dimensional list on this page and any applicable engineering documents.
Frequently Asked Questions
What is a blind flange used for?
A blind flange closes the end of a pipe or a flanged equipment connection. It is commonly used for isolation, maintenance access, valve or nozzle blanking, and future line-extension points.
Does a blind flange have a center bore?
No. A blind flange is a solid flange without a center bore. The mating connection, gasket, and bolting arrangement must still be checked before installation.
Does Class 600 identify one universal working pressure?
No. A flange class designation must be evaluated with the applicable material and temperature conditions. Do not convert the class designation into a working pressure without consulting the governing specification and project requirements.
Why must the mating flange and gasket be verified?
Proper assembly depends on compatibility between the two flange faces, gasket, bolts, and service requirements. A dimensional match alone does not confirm sealing performance or suitability for service.
Can the DWG file be used directly for fabrication?
The DWG is provided for drafting and coordination. Review it against the source dimensions, mating components, material specification, gasket details, and approved fabrication documents before using it for production.
What should be confirmed before installation?
Confirm the flange material, gasket type, bolt specification and length, mating flange details, alignment, access for tightening, and the applicable pressure-temperature requirements.