The Ultimate Guide To Titanium Flanges: Everything You Need to Know

This article is a complete guide to titanium flanges.

There are holes on the titanium flange, and the bolts connect the two flanges tightly. The flanges are sealed with gaskets. Flanged fittings refer to fittings with flanges (flanges or pans).

The flange connection consists of a pair of flanges, a gasket and several bolts and nuts. It can be constructed by threaded connections or by welding. The gasket is placed between the sealing surfaces of the two flanges. After the nut is tightened, the specific pressure on the surface of the gasket will deform when it reaches a certain value, and fill the unevenness on the sealing surface to make the connection tight and leak-proof.

Why choose titanium flange for your piping system? Titanium is an excellent material with a perfect strength-to-weight ratio, good overall formability and workability, it offers the ability to be hot or cold formed while retaining its excellent mechanical properties.

Общая информация

Materials: Titanium Grade F-2 (UNS R50400), Grade F-7 (UNS R52400)

Types: blind, threaded, slip-on, reducing, weld neck, socket weld and lap joint.

Dimensions: ANSI /ASME B16.5, B16.47 Series A & B, B16.48, EN-1092, DIN, etc.

Размер: 1 / 2″ to 24″

Class/ Pressure: 150#, 300#, 600#, 900#, 1500#, 2500#, PN6, PN10, PN16, PN25, PN40, PN64, etc.

Flange Face Type: Flate Face (FF), Raised Face (RF), Ring Type Joint (RTJ)

Поверхность: Forged Surface, Rolled Surface, Turned Surface, Polished Surface

Conditions: annealed titanium and titanium alloy forgings

Production Method: free forging, die forging, precision forging, welding

Detection Method: ray detection, coloring, flaw detection, water pressure test and other tests can be done according to customer needs.

Different Forms of Titanium Industrial Flanges - Guide to Titanium Flanges

Технические характеристики

ASTM B381/ASME SB381: Standard Specification for Titanium and Titanium Alloy Forgings

Guide To Titanium Flanges-ASME/ANSI B16.5 Flanges and Bolt Dimensions – Class 150 to 2500

1 inch = 25.4 mm

Nominal Pipe Size NPS (inches)	Class 150
Nominal Pipe Size NPS (inches)	Diameter of Flange (inches)	No. of Bolts	Diameter of Bolts (inches)	Diameter of Bolt Holes (inches)	Bolt Circle (inches)
1/4	3-3/8	4	1/2	0.62	2-1/4
1/2	3-1/2	4	1/2	0.62	2-3/8
3/4	3-7/8	4	1/2	0.62	2-3/4
1	4-1/4	4	1/2	0.62	3-1/8
1-1/4	4-5/8	4	1/2	0.62	3-1/2
1-1/2	5	4	1/2	0.62	3-7/8
2	6	4	5/8	0.75	4-3/4
2-1/2	7	4	5/8	0.75	5-1/2
3	7-1/2	4	5/8	0.75	6
3-1/2	8-1/2	8	5/8	0.75	7
4	9	8	5/8	0.75	7-1/2
5	10	8	3/4	0.88	8-1/2
6	11	8	3/4	0.88	9-1/2
8	13-1/2	8	3/4	0.88	11-3/4
10	16	12	7/8	1	14-1/4
12	19	12	7/8	1	17
14	21	12	1	1.12	18-3/4
16	23-1/2	16	1	1.12	21-1/4
18	25	16	1-1/8	1.25	22-3/4
20	27-1/2	20	1-1/8	1.25	25
24	32	20	1-1/4	1.38	29-1/2

Guide to Titanium Flanges

Nominal Pipe Size NPS (inches)	Class 300
Nominal Pipe Size NPS (inches)	Diameter of Flange (inches)	No. of Bolts	Diameter of Bolts (inches)	Diameter of Bolt Holes (inches)	Bolt Circle (inches)
1/4	3-3/8	4	1/2	0.62	2-1/4
1/2	3-3/4	4	1/2	0.62	2-5/8
3/4	4-5/8	4	5/8	0.75	3-1/4
1	4-7/8	4	5/8	0.75	3-1/2
1-1/4	5-1/4	4	5/8	0.75	3-7/8
1-1/2	6-1/8	4	3/4	0.88	4-1/2
2	6-1/2	8	5/8	0.75	5
2-1/2	7-1/2	8	3/4	0.88	5-7/8
3	8-1/4	8	3/4	0.88	6-5/8
3-1/2	9	8	3/4	0.88	7-1/4
4	10	8	3/4	0.88	7-7/8
5	11	8	3/4	0.88	9-1/4
6	12-1/2	12	3/4	0.88	10-5/8
8	15	12	7/8	1	13
10	17-1/2	16	1	1.12	15-1/4
12	20-1/2	16	1-1/8	1.25	17-3/4
14	23	20	1-1/8	1.25	20-1/4
16	25-1/2	20	1-1/4	1.38	22-1/2
18	28	24	1-1/4	1.38	24-3/4
20	30-1/2	24	1-1/4	1.38	27
24	36	24	1-1/2	1.62	32

Guide to Titanium Flanges

Nominal Pipe Size NPS (inches)	Class 400
Nominal Pipe Size NPS (inches)	Diameter of Flange (inches)	No. of Bolts	Diameter of Bolts (inches)	Diameter of Bolt Holes (inches)	Bolt Circle (inches)
1/4	3-3/8	4	1/2	0.62	2-1/4
1/2	3-3/4	4	1/2	0.62	2-5/8
3/4	4-5/8	4	5/8	0.75	3-1/4
1	4-7/8	4	5/8	0.75	3-1/2
1-1/4	5-1/4	4	5/8	0.75	3-7/8
1-1/2	6-1/8	4	3/4	0.88	4-1/2
2	6-1/2	8	5/8	0.75	5
2-1/2	7-1/2	8	3/4	0.88	5-7/8
3	8-1/4	8	3/4	0.88	6-5/8
3-1/2	9	8	7/8	1	7-1/4
4	10	8	7/8	1	7-7/8
5	11	8	7/8	1	9-1/4
6	12-1/2	12	7/8	1	10-5/8
8	15	12	1	1.12	13
10	17-1/2	16	1-1/8	1.25	15-1/4
12	20-1/2	16	1-1/4	1.38	17-3/4
14	23	20	1-1/4	1.38	20-1/4
16	25-1/2	20	1-3/8	1.5	22-1/2
18	28	24	1-3/8	1.5	24-3/4
20	30-1/2	24	1-1/2	1.62	27
24	36	24	1-3/4	1.88	32

Guide to Titanium Flanges, Source: tisupplier.com

Nominal Pipe Size NPS (inches)	Class 600
Nominal Pipe Size NPS (inches)	Diameter of Flange (inches)	No. of Bolts	Diameter of Bolts (inches)	Diameter of Bolt Holes (inches)	Bolt Circle (inches)
1/4	3-3/8	4	1/2	0.62	2-1/4
1/2	3-3/4	4	1/2	0.62	2-5/8
3/4	4-5/8	4	5/8	0.75	3-1/4
1	4-7/8	4	5/8	0.75	3-1/2
1-1/4	5-1/4	4	5/8	0.75	3-7/8
1-1/2	6-1/8	4	3/4	0.88	4-1/2
2	6-1/2	8	5/8	0.75	5
2-1/2	7-1/2	8	3/4	0.88	5-7/8
3	8-1/4	8	3/4	0.88	6-5/8
3-1/2	9	8	7/8	1	7-1/4
4	10-3/4	8	7/8	1	8-1/2
5	13	8	1	1.12	10-1/2
6	14	12	1	1.12	11-1/2
8	16-1/2	12	1-1/8	1.25	13-3/4
10	20	16	1-1/4	1.38	17
12	22	20	1-1/4	1.38	19-1/4
14	23-3/4	20	1-3/8	1.5	20-3/4
16	27	20	1-1/2	1.62	23-3/4
18	29-1/4	20	1-5/8	1.75	25-3/4
20	32	24	1-5/8	1.75	28-1/2
24	37	24	1-7/8	2	33

Guide to Titanium Flanges

Nominal Pipe Size NPS (inches)	Class 900
Nominal Pipe Size NPS (inches)	Diameter of Flange (inches)	No. of Bolts	Diameter of Bolts (inches)	Diameter of Bolt Holes (inches)	Bolt Circle (inches)
1/2	4-3/4	4	3/4	0.88	3-1/4
3/4	5-1/8	4	3/4	0.88	3-1/2
1	5-7/8	4	7/8	1	4
1-1/4	6-1/4	4	7/8	1	4-3/8
1-1/2	7	4	1	1.12	4-7/8
2	8-1/2	8	7/8	1	6-1/2
2-1/2	9-5/8	8	1	1.12	7-1/2
3	9-1/2	8	7/8	1	7-1/2
4	11-1/2	8	1-1/8	1.25	9-1/4
5	13-3/4	8	1-1/4	1.38	11
6	15	12	1-1/8	1.25	12-1/2
8	18-1/2	12	1-3/8	1.5	15-1/2
10	21-1/2	16	1-3/8	1.5	18-1/2
12	24	20	1-3/8	1.5	21
14	25-1/4	20	1-1/2	1.62	22
16	27-3/4	20	1-5/8	1.75	24-1/2
18	31	20	1-7/8	2	27
20	33-3/4	20	2	2.12	29-1/2
24	41	20	2-1/2	2.62	35-1/2

Guide to Titanium Flanges

Nominal Pipe Size NPS (inches)	Class 1500
Nominal Pipe Size NPS (inches)	Diameter of Flange (inches)	No. of Bolts	Diameter of Bolts (inches)	Diameter of Bolt Holes (inches)	Bolt Circle (inches)
1/2	4-3/4	4	3/4	0.88	3-1/4
3/4	5-1/8	4	3/4	0.88	3-1/2
1	5-7/8	4	7/8	1	4
1-1/4	6-1/4	4	7/8	1	4-3/8
1-1/2	7	4	1	1.12	4-7/8
2	8-1/2	8	7/8	1	6-1/2
2-1/2	9-5/8	8	1	1.12	7-1/2
3	10-1/2	8	1-1/8	1.25	8
4	12-1/4	8	1-1/4	1.38	9-1/2
5	14-3/4	8	1-1/2	1.62	11-1/2
6	15-1/2	12	1-3/8	1.5	12-1/2
8	19	12	1-5/8	1.75	15-1/2
10	23	12	1-7/8	2	19
12	26-1/2	16	2	2.12	22-1/2
14	29-1/2	16	2-1/4	2.38	25
16	32-1/2	16	2-1/2	2.62	27-3/4
18	36	16	2-3/4	2.88	30-1/2
20	38-3/4	16	3	3.12	32-3/4
24	46	16	3-1/2	3.62	39

Guide to Titanium Flanges

Nominal Pipe Size NPS (inches)	Class 2500
Nominal Pipe Size NPS (inches)	Diameter of Flange (inches)	No. of Bolts	Diameter of Bolts (inches)	Diameter of Bolt Holes (inches)	Bolt Circle (inches)
1/2	5-1/4	4	3/4	0.88	3-1/2
3/4	5-1/2	4	3/4	0.88	3-3/4
1	6-1/4	4	7/8	1	4-1/4
1-1/4	7-1/4	4	1	1.12	5-1/8
1-1/2	8	4	1-1/8	1.25	5-3/4
2	9-1/4	8	1	1.12	6-3/4
2-1/2	10-1/2	8	1-1/8	1.25	7-3/4
3	12	8	1-1/4	1.38	9
4	14	8	1-1/2	1.62	10-3/4
5	16-1/2	8	1-3/4	1.88	12-3/4
6	19	8	2	2.12	14-1/2
8	21-3/4	12	2	2.12	17-1/4
10	26-1/2	12	2-1/2	2.62	21-1/4
12	30	12	2-3/4	2.88	24-3/8

Guide to Titanium Flanges

Pressure(psig)And Temperature Ratings

Corresponding relationship between pressure level and PN

In your list, some pressure levels are measured in “Class” units (such as 75, 150, 300, 600, 900, 1500, 2500), while others are measured in “PN” units (such as PN 2.5 to PN 400). The correspondence between these two units is not direct, as “Class” is the nominal pressure rating in American standards (such as ANSI/ASME), while “PN” is the pressure rating representation method in European standards (such as DIN/EN). However, in order to roughly understand the correspondence between them, the following conversion relationships can be referred to (note that this is only a rough correspondence, specific reference should be made to relevant standards):

Class 150 ≈ PN 2.0 MPa
Class 300 ≈ PN 5.0 MPa
Class 600 ≈ PN 11.0 MPa
Class 900 ≈ PN 15.0 MPa
Class 1500 ≈ PN 26.0 MPa
Class 2500 ≈ PN 42.0 MPa

For non-standard “Class 75” и “PN 400”, it should be noted that “Class 75” may be a non-standard or application specific pressure rating, while “PN 400” far exceeds the common PN rating range and may require special design and manufacturing.

Titanium Flanges	Pressure Rating Chart
Temperature °F	150#	300#	400#	600#	900#	1500#	2500#
-20-100	275	720	960	1440	2160	3600	6000
200	230	600	800	1200	1800	3000	5000
300	205	540	720	1080	1620	2700	4500
400	190	495	660	995	1490	2485	4140
500	170	465	620	930	1395	2330	3880
600	140	435	580	875	1310	2185	3640
650	125	430	575	860	1290	2150	3580
700	110	425	565	850	1275	2125	3540
750	95	415	555	830	1245	2075	3460
800	80	405	540	805	1210	2015	3360
850	65	395	530	790	1190	1980	3300
900	50	390	520	780	1165	1945	3240
950	35	380	510	765	1145	1910	3180
1000	20	320	430	640	965	1605	2675
1050	20	310	410	615	925	1545	2570
1100	20	255	345	515	770	1285	2145
1150	20	200	265	400	595	995	1655
1200	20	155	205	310	465	770	1285
1250	20	115	150	225	340	565	945
1300	20	85	115	170	255	430	715
1350	20	60	80	125	185	310	515
1400	20	50	65	95	145	240	400
1450	15	35	45	70	105	170	285
1500	10	25	35	55	80	135	230

Guide to Titanium Flanges

ASTM B381 Titanium Flanges Available Types & Формы

ASTM B381 Titanium Blind Flanges
ASTM B381 Titanium Threaded / Screwed Flanges
ASTM B381 Titanium Slip On Flanges
ASTM B381 Titanium Weld Neck Flanges
ASTM B381 Titanium Socket Weld Flanges
ASTM B381 Titanium Plate Flanges
ASTM B381 Titanium Lap Joint Flanges
ASTM B381 Titanium Long Weld Neck Flanges
ASTM B381 Titanium Reducing Flanges
ASTM B381 Titanium Ring Type Joint Flanges
ASTM B381 Titanium Tongue & Groove Flanges

Guide To Titanium Flanges – FAQ

What are the main advantages of titanium alloy flanges compared to other materials such as stainless steel?

The main advantages of titanium alloy flanges are their high strength to weight ratio, excellent corrosion resistance, and fatigue resistance. Compared with stainless steel, titanium alloy can maintain stable performance in more extreme temperatures and corrosive environments, while being lighter in weight, which helps to reduce overall equipment weight and improve energy efficiency.

How to choose the appropriate titanium alloy flange grade based on work pressure and temperature?

When choosing the grade of titanium alloy flange, it is necessary to consider the working pressure, temperature, and corrosiveness of the medium. Usually, flange grades (such as ASTM B338 grades 1 to 9) specify different chemical compositions and mechanical properties to accommodate different application conditions. It is recommended to refer to relevant industry standards or consult suppliers to select the most suitable grade based on specific working conditions.

How to check the quality of titanium alloy flanges?

Testing the quality of titanium alloy flanges usually includes chemical composition analysis, mechanical property testing (such as tensile strength, yield strength), non-destructive testing (such as ultrasonic testing, X-ray testing), and inspection of appearance dimensions and form tolerances. These testing items can comprehensively evaluate whether the quality of the flange meets the standard requirements.