Blind Flange

Product Description

1. Product Introduction

A Blind Flange is a flange with no bore — a solid circular plate that is bolted to another flange face to create a pressure seal. Its function is analogous to a bottle cap: it closes off the open end of a pipe system completely. The blind face carries the full gasket load from the bolt circle, and the gasket seats against the raised face (RF), flat face (FF), or ring joint groove (RTJ) on the blind's face, creating a leak-proof pressure boundary. Blind flanges are specified for four principal uses: first, as permanent pipe end terminations where the pipeline terminates without further extension; second, as test blanks during hydrostatic or pneumatic pressure testing of a pipe system before it is put into service; third, as maintenance blanks that can be removed during plant shutdowns for access to equipment or lines upstream of the blind; and fourth, as spectacle blind flanges that combine a blind and a spacer in one rotating flanged element for isolating and bypassing flow lines. The blind flange must be thick enough to resist the bending moment created by the pressure load acting on its unsupported center — the calculation of this minimum thickness is a fundamental part of the ASME B16.5 blind flange design basis, and it increases with both pressure class and diameter. Full-face gaskets or RTJ gaskets distribute the bolt load evenly across the sealing face.

2. Product Features

- Full-pressure-containing plate design with calculated minimum thickness

- RF, FF, and RTJ facing options for all standard and ring gasket types

- Solid bore — creates complete pressure isolation of the downstream system

- Can be used as temporary test blank or permanent end seal

- Materials: carbon steel, alloy steel, stainless steel for all conditions

3. Core Specifications

Parameter	Specification
Size Range	1/2" – 80" NPS
Pressure Rating	CL150 – CL2500; PN10/PN16/PN40
Facing	RF (Raised Face), FF (Flat Face), RTJ (Ring Type Joint)
Construction	Solid plate — full pressure-containing bore closure
Use	Permanent seal, test blank, maintenance blank, or spectacle spacer-blind
Materials	Carbon steel, alloy steel, stainless steel
Standards	ASME B16.5, B16.47, AWWA C207, MSS SP-44, EN 1092-1
Certifications	API, ISO 9001, ISO 14001, ISO 45001, CE

4. Materials

- Carbon steel: ASTM A105; ASTM A350 LF2 for cryogenic service to -46°C

- European: P235GH, P245GH, P265GH, P280GH for EN-standard equipment

5. Product Standards

- MSS SP-44 — Steel Pipeline Flanges

6. Applications

- Permanent end terminations of pipe headers and manifold branches in process plants

- Pressure test blanks during pre-commissioning hydrostatic testing of piping systems

- Maintenance blanks for isolating equipment during turnaround and shutdown periods

- Spectacle blind spacer-blind configurations for process line isolation and bypass

- Tanks, vessels, and pressure equipment nozzle closures in refineries and chemical plants

- Offshore platform and subsea pipeline end seals for abandoned or suspended lines

7. Packaging

8. Customization

Non-standard thicknesses for test pressures above rated working pressure, orifice blind configurations with metering plate, and spectacle blind combinations (blind + spacer) for standard and non-standard pipe schedules. Special alloys for H₂S and sour gas service.

For more information, please visit our website.

Other supplier products

	Weld Neck Flange	Product Description 1. Product Introduction The distinguishing feature of a Weld Neck Flange is its long, tapered hub — often called the ...
	Steel Pipe Bend Manufacturer | 3D, 5D & 10D Bends	Product Description 1. Product Introduction Unlike standard elbows which are manufactured from pipe or forgings in fixed angle increments, bend...
	Blind Flange	Product Description 1. Product Introduction A Blind Flange is a flange with no bore — a solid circular plate that is bolted to another fl...
	Spectacle Blind Flange	Product Description 1. Product Introduction The Spectacle Blind Flange is named for its shape: when the assembled flange element is viewed from...
	Forged Steel Elbow	Product Description 1. Product Introduction Forged Elbows are produced by heating a steel bar or billet and forcing it into a closed-die forgin...

供应产品

Same products

	Oil and Gas Pipe Fittings	卖方: Hebei Longrun Pipeline Group CO., Ltd	Industry Overview Refined petroleum products—including gasoline, diesel, jet fuel, and f...
	Spectacle Blind Flange	卖方: Hebei Longrun Pipeline Group CO., Ltd	Product Description 1. Product Introduction The Spectacle Blind Flange is named for its shape...
	Blind Flange	卖方: Hebei Longrun Pipeline Group CO., Ltd	Product Description 1. Product Introduction A Blind Flange is a flange with no bore — a...
	Threaded Flange	卖方: Hebei Longrun Pipeline Group CO., Ltd	Product Description 1. Product Introduction Threaded Flanges offer a unique advantage in indu...
	Socket Weld Flange	卖方: Hebei Longrun Pipeline Group CO., Ltd	Product Description 1. Product Introduction The Socket Weld Flange is specifically designed f...