Blind Flange (BL)
Yunming Metal offers stainless steel blind flanges (BL) in sizes DN15–DN3000. Designed for pipeline closure and pressure vessel ends, they are available in 304, 316L, 321, and 904L. Precision-machined with raised, flat, or RTJ faces. Supports Class 150–2500 and PN6–PN100.
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Product Overview
Blind flanges (BL flanges) are solid disks used to close off the ends of piping systems or pressure vessel openings. They allow easy access for inspection, cleaning, or modification of the pipeline. Stainless steel blind flanges provide exceptional durability and corrosion resistance, making them ideal for demanding industrial applications. With size availability from DN15 to DN3000, they support a wide range of international standards and pressure ratings.
Application Areas
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Petrochemical pipelines
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Oil and gas facilities
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Water treatment and wastewater systems
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Power plants and pressure vessels
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Food and pharmaceutical processing
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Marine and shipbuilding industries
Product Features
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Full face sealing with no internal bore
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Available in flat face (FF), raised face (RF), and ring type joint (RTJ)
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Supports pressure ratings from Class 150 to 2500 and PN6 to PN100
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Size range from DN15 to DN3000
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Machined surface ensures leak-proof sealing
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Made from corrosion-resistant stainless steel grades including 304, 316L, 321, 310S, 904L, and duplex steel
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Easy disassembly and reassembly for maintenance or expansion
Technical Specifications
| Parameter | Range |
|---|---|
| Nominal Size (DN) | DN15 – DN3000 |
| Outside Diameter (OD) | 34 mm – 3200 mm (approx. 1⁵⁄₁₆″ – 126″) |
| Thickness (T) | 10 mm – 120 mm (approx. ³⁄₈″ – 4¾″) |
| Pressure Ratings | Class 150 – Class 2500 / PN6 – PN100 |
| Material Grades | ASTM A182 F304 / F316 / F316L / F321 / 310S / 904L / 2205 etc. |
| Standards | ANSI B16.5, EN 1092-1, JIS B2220, DIN, BS, GB, ISO etc. |
| Type | Blind Flange (BL), available with RF / FF / RTJ face types |
| Connection Type | Full face sealing – no bore, drilled bolt holes for secure connection |
| Surface Finish | CNC machined, anti-rust oil coating |
| Application | Construction, petroleum, chemical, shipbuilding, water systems, power, metallurgy, HVAC, and general industry |
Manufacturing Process
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Raw Material Selection – Choose stainless steel billets or plates according to customer requirements
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Blank Cutting – Material is cut into round blanks per specified diameter and thickness
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Forging and Shaping – Flanges are shaped and flattened as per standard
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CNC Machining – Precision machining of faces and bolt holes
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Surface Treatment – Anti-rust oil application and optional polishing
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Inspection & Packaging – Dimensional and quality checks before packaging
FAQ
Q1: What’s the difference between a blind flange and a weld neck flange?
A: A blind flange is solid and used to block off a pipe end, whereas a weld neck flange connects two pipe ends and has a bore.
Q2: Do you offer large-size blind flanges?
A: Yes, we supply stainless steel blind flanges up to DN3000 (approx. 120″).
Q3: Can blind flanges handle high pressure?
A: Absolutely. We provide Class 150 to Class 2500 and PN6 to PN100 rated blind flanges.
Q4: Which face types do you support?
A: We offer raised face (RF), flat face (FF), and ring type joint (RTJ) options.
Q5: Do you supply MTCs and third-party inspection?
A: Yes. EN 10204 3.1/3.2 material test certificates and third-party inspection can be provided.
Still have questions?
Feel free to contact us for more details or to discuss your custom stainless steel blind flange requirements. Our technical support team is ready to assist with specifications, certifications, and delivery.
