ASME B16.48 Duplex Spectacle Blind Flange Exporter Manufacturer, Supplier & Exporter | Ragnar Metals & Tubes

• Direct manufacturer — Competitive mill prices
• ISO & third-party inspected — EN 10204 MTCs
• Export-ready packaging and global logistics

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ASME B16.48 Spectacle Blinds — Duplex Pipe Isolation

ASME B16.48 covers line blanks, spacers and spectacle blinds for NPS ½–24 in Class 150–2500. A spectacle blind combines a solid disc (blind) and open ring (spacer) in a figure-8 shape — rotate the correct side between flanges for positive pipe isolation or reinstatement without removing any component. Critical during plant maintenance and shutdown turnarounds in oil & gas, petrochemical and power plant piping.

Duplex S31803 spectacle blinds are machined from A240/SA-240 forged or rolled plate. Charpy impact at −46°C minimum 27 J. NACE MR0175 compliant. Tabs laser-engraved with heat number, material grade, pressure class and B/S designation. EN 10204 3.1 MTC per heat supplied as standard.

ASME B16.48 Duplex Spectacle Blind & Paddle Blank Specifications

ASME B16.48 covers line blinds — spectacle blinds (figure-8), paddle blanks (pancake blinds), and paddle spacers — used for positive isolation in process piping systems. Duplex stainless steel ASME B16.48 spectacle blinds are specified for corrosive service where spade blinds could corrode and seize between flanges. The standard defines dimensional criteria including handle height, flange-to-flange thickness, ring groove face finish (for RTJ service), and bolt pattern matching ASME B16.5 for the same pressure class. Duplex B16.48 blanks in grades ASTM A240 S31803 and S32750 are used in chloride service where carbon steel blinds are not acceptable per NACE requirements.

Component	Description	Material Grade	NPS Range
Spectacle Blind	Figure-8: one open ring + one solid plate, hinged	ASTM A240 S31803/S32750	NPS 1/2–24
Paddle Blank (Spade)	Solid plate for positive isolation; handle inscribed BLIND	ASTM A240 S31803/S32750	NPS 1/2–60
Paddle Spacer (Paddle Ring)	Open ring to maintain flange gap when spade removed	ASTM A240 S31803/S32750	NPS 1/2–60

B16.48 Spectacle Blind Applications

• Process unit turnaround isolation during shutdown maintenance on offshore platforms
• Double-block isolation in corrosive acid and alkali service lines
• Test and commissioning isolation in new chemical plant piping
• Positive isolation of toxic gas and chlorine service piping
• Hydrostatic pressure test isolation in subsea pipeline commissioning

About Ragnar Metals & Tubes

Ragnar Metals & Tubes is a trusted manufacturer, supplier, and global exporter of high-performance metal products including fasteners, fittings, pipes, tubes, flanges, and custom-engineered components. With a strong export presence in USA, UK, Germany, UAE, Saudi Arabia, Canada, Australia, and 50+ countries, we are known for delivering precision-engineered solutions for critical and high-temperature industrial applications.

Our manufacturing facility follows strict quality control systems with ISO 9001, ISO 14001, and ISO 45001 certification. Every product is tested and supplied with EN 10204 3.1 / 3.2 Material Test Certificates, ensuring complete material traceability and compliance with international standards such as ASTM, ASME, DIN, EN, and BS.

We cater to bulk industrial buyers, EPC contractors, and engineering projects across oil & gas, petrochemical, marine, power generation, aerospace, offshore drilling, and heavy engineering sectors. With flexible manufacturing, custom dimensions, and fast global delivery, we ensure reliable, consistent, and timely supply for all project requirements.

Why Choose Ragnar Metals & Tubes

• 50+ Countries served
• 24/7 RFQ Support
• Fastest delivery
• Direct manufacturer with bulk stock and fast lead times
• ISO 9001 certified production and documented QA
• Global shipping with export-grade packaging
• EN 10204 3.1 / 3.2 MTCs, third-party inspection on request
• Global export experience to USA, UK, EU, MENA & APAC
• Custom sizes and drawing-based manufacturing
• Faster quotations — send quantity, grade and dimensions
• Bulk quantity available at factory price
• 100% traceability with heat number stamping

Testing & Quality Inspection Process

At Ragnar Metals & Tubes, our testing process is designed to ensure the reliability, durability, and performance of every product we manufacture—including Pipes & Tubes, Fittings, Flanges, Sheets & Plates, Fasteners, and Rods & Bars. All testing follows internationally recognized standards such as ASTM, ASME, ISO, EN, and DIN.

Each batch undergoes multiple inspection stages starting from raw material verification to final dispatch. Our advanced laboratories perform chemical, mechanical, and non-destructive tests to ensure full compliance and traceability.

Types of Tests Performed

Ultrasonic Testing (UT)

Detects internal defects using high-frequency sound waves without damaging the material.

Hardness Testing

Checks resistance to deformation to ensure materials meet mechanical strength requirements.

Surface Finish Inspection

Examines surface quality, cracks, and finishing accuracy for high-precision applications.

Impact Test (Charpy V-Notch)

Measures impact resistance and toughness under varying temperature conditions.

Heat Treatment Report

Ensures optimal mechanical properties through controlled heating and cooling processes.

Tensile Test

Evaluates tensile strength, yield strength, and elongation to verify compliance with standards.

Quality Documentation & Traceability

Every batch is certified and supported with complete documentation including EN 10204 3.1 / 3.2 Material Test Certificates (MTC), heat number traceability, and third-party inspection reports (SGS, TUV, BV, Lloyds) upon request.

Our testing technicians are trained to follow strict procedures, ensuring that Ragnar Metals & Tubes maintains its reputation as a reliable global supplier trusted across the Oil & Gas, Petrochemical, Marine, Power, and Heavy Engineering industries.

Available Grades Table

ASME B16.48 Duplex Spectacle Blind Flange Exporter	Composition	Applications
2205 (Duplex)	22% Cr, 5% Ni, 3% Mo	Oil & gas, marine applications
2507 (Super Duplex)	25% Cr, 7% Ni, 4% Mo	Aggressive chloride environments
304L	18% Cr, 8% Ni (low carbon)	Welded components, chemical industry
316L	16% Cr, 10% Ni, 2% Mo (low carbon)	Medical implants, welded structures
904L	20% Cr, 25% Ni, 4.5% Mo, Cu	Severe corrosion environments

Specifications Table

Material	ASME B16.48 Duplex Spectacle Blind Flange Exporter
Grades	2205, 2507, 304L, 316L, 904L
Standard	ASTM A240 / A312 / A213
Size Range	1" NB to 30" NB (Seamless), 1" NB to 48" NB (Welded)
Length	Single Random, Double Random & Custom Cut
Form	Round, Square, Rectangular

Chemical Properties Table

Element	2205 (%)	2507 (%)
Carbon (C)	0.03 max	0.03 max
Chromium (Cr)	22.0–23.0	25.0–26.0
Nickel (Ni)	4.5–6.5	6.0–8.0
Manganese (Mn)	2.0 max	1.0 max
Silicon (Si)	1.0 max	1.0 max
Phosphorus (P)	0.03 max	0.03 max
Sulfur (S)	0.02 max	0.02 max
Molybdenum (Mo)	3.0–5.0	4.0–5.0

Mechanical Properties Table

Property	2205	2507
Tensile Strength (MPa)	620 min	1000 min
Yield Strength (MPa)	450 min	750 min
Elongation (%)	25 min	20 min
Hardness (HRB)	95 max	98 max

ASME B16.48 Duplex Spectacle Blind Flange Exporter Price List (2025)

Material Grade	Thickness	Price (USD / Kg)	Price (INR / Kg)
2205 (Duplex)	3 mm	$3.50 – $4.10	₹280 – ₹320
2507 (Super Duplex)	6 mm	$4.00 – $4.80	₹310 – ₹370
2205 (Duplex)	10 mm	$4.50 – $5.20	₹340 – ₹400

Note: The above prices are for reference only. Actual pricing may vary based on size, thickness, quantity, raw material cost, and delivery location. Contact us to get the best and most updated pricing for ASME B16.48 Duplex Spectacle Blind Flange Exporter.

Lead Time

2–7 weeks depending on size

Delivery Terms

FOB, CIF, DDP

Shipping Modes

Sea / Air / Express

Export Packaging & Shipping

• Sea-worthy fumigated wooden crates with waterproof lining
• Palletised boxing with clear shipping marks & heat number labels
• Container stuffing supervision and loading photos on request

MOQ & Payment Terms

Minimum Order Quantity: 25–100 Kg depending on part size and grade.

Payment Terms: Depending On Grade and Quantity Size

Applications & Uses

• Oil & Gas Industry
• Petrochemical Plants
• Water Treatment Plants
• Pharmaceutical Industry
• Food & Beverage Industry
• Automobile Industry

Cities We Suppllied In India

We exported to 50+ countries worldwide.

Frequently Asked Questions

Do you provide Material Test Certificates?

Yes, we provide EN 10204 3.1 / 3.2 Material Test Certificates with complete chemical and mechanical analysis for every shipment.

What is the Minimum Order Quantity (MOQ)?

MOQ generally ranges between 25–100 Kg depending on product size, grade and specifications.

Do you export to USA, Europe and UAE?

Yes, we ship worldwide including USA, UK, Germany, UAE, Saudi Arabia, Canada and Australia.

What are your payment terms?

Typical payment terms are 30% advance and 70% against copy of shipping documents. Payments via T/T, LC and SWIFT are accepted.

What packaging do you use for export?

All products are packed in sea-worthy fumigated wooden boxes with waterproof lamination, pallet loading and shipment marking for traceability.

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