Blind Flange - Industrial Sealing Solutions
Engineering-grade blind flange products produced in accordance with ANSI/ASME B16.5 and ASME B16.47 specifications are the specialty of XI AN LINHUI. A solid steel disk called a "flange" is used to completely isolate pipelines, valves, and pressure vessel openings. Our products are made of forged carbon steel (ASTM A105) and stainless steel (ASTM A182 F304/F316), with pressure ratings ranging from Class 150 to 2500 and sizes ranging from 1/2" to 60" (DN15 to DN1500). To guarantee dimensional accuracy within ±0.05mm, each product is subjected to heat treatment and CNC machining. Our flanges provide leak-proof performance in high-temperature and high-pressure settings with facing styles like Raised Face (RF), Flat Face (FF), and Ring Type Joint (RTJ).
Key Features & Benefits
Our Blind Flange provides absolute isolation for maintenance without cutting pipes. It bears total internal system pressure, making it essential for hydraulic testing and safe access during cleaning or inspection.
The design handles maximum bending stress at the plate center, ensuring structural integrity. You benefit from modular sealing via multiple face types, supporting diverse pressure and temperature conditions.
Manufacturing Process
For exceptional grain structure, each product starts with forged billets. Heat treatment improves mechanical qualities and normalizes stress.
Tight tolerances for bolt hole alignment and flange face flatness are guaranteed by CNC machining. Your requirements are met by the final surface finishes (polished or pickled).
Before shipping, 100% dimensional check confirms compliance.
Quality Inspection
ASME-compliant visual and dimensional inspections
Hardness testing (Rockwell/Brinell)
NDT for interior faults using eddy current and ultrasonic
Testing for hydrostatic pressure is available.
Upon request, third-party inspection (SGS, BV, TÜV, DNV)
Applications Of Blind Flange
Oil & Gas: Sealing pipeline terminations and pressure vessels for maintenance access.
Chemical Processing: Isolation of reactors and storage tanks handling corrosive fluids.
Marine & Offshore: Dead-leg capping in seawater cooling systems and fire water lines.
Power Generation: Steam and cooling system isolation during outages.
Export Markets
LINHUI has supplied more than 60 nations with hundreds of thousands of tons. North America, the Middle East, Southeast Asia, Europe, and South America are important markets.
CEFC, PTT, PDVSA, PETRONAS, and LUKOIL are among the EPC contractors we work with.
Why Choose Us
Direct mill supply eliminates middlemen, offering factory pricing. Our 200+ tons of stock inventory ensures delivery within 3–7 days for standard items.
Engineering support team provides technical consultation and material selection guidance. ISO 9001:2015 certification and full traceability via heat numbers guarantee quality.
Flexible MOQ supports trial orders from 100 kg. Multilingual service teams assist global clients in English, Chinese, Spanish, and Arabic.
Packaging & Shipping
Flanges are wrapped in waterproof film and packed in plywood cases or steel crates. Marking includes heat numbers and specification labels.
We arrange sea freight, air cargo, or express delivery based on your urgency. Export documentation (MTC, packing list, certificate of origin) is provided promptly.
FAQ
Q: Why is a Blind Flange thicker than other flange types?
A: It bears significant bending stress at the center due to internal pressure, requiring greater thickness for structural integrity.
Q: Can a Blind Flange be modified for instrumentation?
A: Yes. They can be drilled and tapped (typically 1/2" or 3/4" NPT) to accommodate pressure gauges or drain valves—often called a 'tapped blind'.
Q: When should I use an RTJ face?
A: RTJ is recommended for Class 600+ or high-temperature lines, ensuring metal-to-metal seal under cyclic stress.
Q: How do I verify load capacity?
A: Check the Heat Number against the Mill Test Certificate for tensile/yield strength, ensuring pressure class matches system design per ASME B16.5 tables.
Request a Quote
Do you need precise specifications or volume pricing for Blind flange? Contact our engineering team at linhui@lhtitanium.com to receive a detailed quotation within 4 hours. Let us support your project success.
