This reference provides the dimensional and installation-related data for a Blind Flange 1 1/2 Inch Class 900. Use the listed values when checking piping layouts, preparing fabrication details, coordinating flange connections, or downloading the associated DWG file.
A blind flange has no center bore, so its primary function is closure rather than allowing fluid to pass through. The flange class, nominal size, bolt arrangement, and sealing details should be reviewed together with the project specification before procurement or installation.
Blind Flange 1 1/2″ Class 900
Blind Flange 1 1/2″ Class 900 is used to seal the end of a piping system or close off a flange connection in Class 900 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 1 1/2″ Class 900 Dimensions
- Reference Standard: ANSI / ASME B16.5
- Nominal Pipe Size (NPS): 1 1/2″
- DN Size: DN40
- Flange Thickness: 31.8mm
- Weight: 5.9kg
- Stud Bolt Size: 1″ UNC (or M27) x 140 Long
- Number of Bolts: 4
- Hole Diameter: 1 1/8″ (28.575mm)
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 1 1/2″ Class 900 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 1 1/2″ Class 900, which can be used for drafting, detailing, and piping layout coordination.
Available Blind Flange Class 900 Sizes
This size is part of the Blind Flange Class 900 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
The source data identifies the flange as NPS 1 1/2 and DN40. These size labels describe the same nominal piping connection using commonly used inch-based and metric terminology. They should not be treated as the measured outside diameter of the flange or pipe.
For drafting, the flange thickness, hole diameter, number of bolts, and stud bolt description are the key items for representing the connection. The bolt count and hole information help establish the bolt-circle layout in a drawing, while the stud bolt size and length support connection-detail review. Confirm the actual mating flange, gasket arrangement, washer requirements, and tightening procedure from the project documents.
Design and Drafting Checks
- Match the blind flange to the connected flange class and nominal size.
- Check that the flange facing and gasket selection are compatible with the mating connection.
- Review the listed bolt arrangement against the assembly drawing and project specification.
- Use the published weight for handling and material-planning discussions, not as a substitute for a verified lifting plan.
- Confirm material, service conditions, pressure-temperature requirements, and fabrication requirements before release.
For related research, compare this page with the site’s flange dimensions, pipe schedules, flange facing terminology, gasket selection, stud bolt references, and other Class 900 blind flange sizes. Those references can help keep piping models, isometric drawings, and procurement descriptions consistent.
Using the CAD File
The linked DWG resource can support preliminary layout, detailing, and coordination. Treat downloaded geometry as a drafting reference: verify units, layers, connection orientation, facing details, and project-specific changes before incorporating it into a controlled design deliverable.
Blind Flange 1 1/2 Inch Class 900 FAQ
What is a blind flange used for?
A blind flange closes the end of a pipeline, vessel nozzle, valve connection, or other flanged opening. It can support isolation, maintenance access, and planned future connection work.
What do NPS 1 1/2 and DN40 mean?
They are nominal size designations for the flange connection. NPS uses the inch-based piping designation, while DN is the corresponding metric nominal designation shown in the source data.
Does a blind flange have a center bore?
No. A blind flange is a solid flange without a center bore, which allows it to block the connected opening.
What bolt information is provided for this flange?
The reference lists the stud bolt size and length, the number of bolts, and the hole diameter. Confirm the final bolting arrangement, material, gasket, and tightening requirements against the project specification.
Can the DWG be used directly for fabrication?
The DWG is intended for drafting, detailing, and layout coordination. It should be checked against the applicable project requirements and verified by the responsible engineering or fabrication team before use for manufacture.
What should be confirmed before installation?
Confirm the flange material, gasket type, bolt requirements, mating flange, applicable pressure-temperature rating, and current project requirements before fabrication or installation.