Titanium Grade 5 Flanges

Titanium Grade 5 (F-5, Ti-6Al-4V, UNS R56400) Flanges to ASTM B381 and ASME B16.5

Dinesh Tube India supplies and exports titanium Grade 5 flanges from Mumbai for high-pressure, offshore and weight-critical piping. Grade 5 flanges are machined from forgings to ASTM B381 / ASME SB381 Grade F-5 (Ti-6Al-4V, UNS R56400, Werkstoff 3.7165), with dimensions to ASME B16.5, and are supplied with EN 10204 3.1 mill test certificates.

Grade 5 is the high-strength titanium alloy: about 2.6 times as strong as Grade 2, at about 56% of the weight of a steel flange. It is chosen for strength and weight, not for chemical corrosion. For corrosive process piping, Grade 12 or Grade 2 flanges are usually the better choice. For all grades, see our titanium flanges page.

Table of Contents

Grade 5 Flange Types
Specification & Sizes
When to Use Grade 5
F-5 vs F-2 vs F-12
Chemical Composition
Mechanical Properties
Applications
FAQs

Titanium Grade 5 F-5 Ti-6Al-4V flanges to ASTM B381

Titanium Grade 5 Flange Types

Weld Neck Flange

Butt-welded to the pipe; the best choice for higher pressure and cyclic service.

Slip-On Flange

Slides over the pipe and is fillet-welded; for lower-pressure lines.

Blind Flange

Closes pipe ends, nozzles and vessel openings.

Socket Weld Flange

For small-bore lines, usually 2" NPS and below.

Threaded Flange

For small-bore lines; check thread galling (use anti-seize).

Lap Joint & RTJ

Lap-joint flanges with stub ends, and ring-type-joint faces on request.

When to Use a Grade 5 Flange

Good fit: high-pressure joints, offshore and subsea hardware, weight-critical piping and equipment, and lines where Grade 5 pipe or parts are already specified.
Usually not needed: seawater, chlorine and chemical piping at normal pressures. There, Grade 2 or Grade 12 flanges cost less and resist corrosion better.
Lap-joint alternative: where only strength is needed at the bolting, a titanium stub end with a steel backing flange can be cheaper than a solid F-5 flange.

F-5 vs F-2 vs F-12 Flanges

Point	F-2 (Grade 2)	F-12 (Grade 12)	F-5 (Grade 5)
Min. tensile / yield	345 / 275 MPa	483 / 345 MPa	895 / 828 MPa
Min. elongation	20%	18%	10%
Seawater, chlorine	Excellent	Excellent	Good
Hot-brine crevices, reducing acids	Fair / poor	Excellent / good	Fair / poor
Main reason to choose	Corrosion at lowest cost	Hot-brine corrosion plus strength	Highest strength-to-weight

Titanium Grade 5 Flange Chemical Composition (ASTM B381 F-5, %)

Element	F-5
Aluminium (Al)	5.5–6.75
Vanadium (V)	3.5–4.5
Iron (Fe), max	0.40
Oxygen (O), max	0.20
Carbon (C), max	0.08
Nitrogen (N), max	0.05
Hydrogen (H), max	0.015
Titanium (Ti)	Balance

Titanium Grade 5 Flange Mechanical Properties (Minimum)

Tensile Strength	Yield Strength (0.2%)	Elongation (4D)	Reduction of Area	Density
895 MPa (130 ksi)	828 MPa (120 ksi)	10%	25%	4.43 g/cm³ (0.160 lb/in³)

Annealed condition. Check the current ASTM B381 edition (B381-26) and the mill certificate for governing values.

Need Grade 5 titanium flanges? Send the flange type, NPS, class, facing, bore and quantity to kamlesh@dineshtube-india.com or call +91 83559 10913. You can also send an enquiry.

Marking, Bolting and Welding

Marking: a typical flange marking reads maker's mark, ASTM B381 F-5, size, class, facing, bore and heat number.
Galling: titanium threads and faces can gall; use anti-seize on titanium bolting and avoid over-torquing.
Welding: GTAW with full argon shielding and back purge, using ERTi-5 filler; weld procedures for Grade 5 need more care than for Grade 2.
Dissimilar metals: isolate titanium from carbon steel or aluminium where seawater can bridge the joint.

Titanium Grade 5 Flange Applications

Offshore and subsea hardware and risers
High-pressure process and test lines
Marine and naval weight-critical piping
Specialised equipment built from Grade 5 parts
Motorsport and high-performance systems

Offshore, marine and high-pressure uses of titanium Grade 5 flanges

Titanium Grade 5 Flanges: FAQs

Which standard covers titanium Grade 5 flanges?

The flange material is covered by ASTM B381 (ASME SB381) Grade F-5, the specification for titanium alloy forgings. Flange dimensions follow ASME B16.5, with B16.47 for sizes above 24".

What is F-5 titanium?

F-5 is the ASTM B381 forging grade of titanium Grade 5, also called Ti-6Al-4V (UNS R56400, Werkstoff 3.7165), an alloy with about 6% aluminium and 4% vanadium.

Why choose a Grade 5 titanium flange?

Grade 5 has a minimum yield strength of 828 MPa, about three times that of Grade 2, at about 56% of the weight of steel. It suits high-pressure and weight-critical joints.

Are Grade 5 flanges good for corrosive chemical service?

Grade 5 resists seawater well, but Grade 2, 12 or 7 flanges are better for hot brines, crevices and reducing acids, and cost less. Grade 5 is chosen mainly for strength.

Which types of Grade 5 flanges are available?

Weld neck, slip-on, blind, socket weld, threaded and lap-joint flanges, with raised face, flat face or ring-type-joint facing, mostly made to order.

What is the price of titanium Grade 5 flanges?

The price depends on flange type, NPS, class, facing, quantity and certification. Send your requirement to kamlesh@dineshtube-india.com or call +91 83559 10913 for a current quote.

Which certificates come with Grade 5 flanges?

Every supply comes with an EN 10204 3.1 mill test certificate showing heat number, chemical analysis and mechanical properties to ASTM B381. EN 10204 3.2 certificates and third-party inspection can be arranged on request.

Export Destinations for Titanium Grade 5 Flanges

We supply titanium Grade 5 flanges across India to fabricators and engineering buyers in Maharashtra, Gujarat, Karnataka, Tamil Nadu and Telangana, and export to the Middle East (UAE, Saudi Arabia, Qatar, Oman, Kuwait, Bahrain), Asia (Singapore, Malaysia, Vietnam, Bangladesh), Africa (Egypt, Nigeria, South Africa) and Europe on request.