Blind Flanges | ASME B16.5 | ASME B16.47

PM Industries manufactures, supplies, and stocks Blind Flanges in a range of materials, pressure classes, and pipe sizes. A blind flange is a solid flange with no center bore. It bolts to the end of a pipe, nozzle, or vessel opening using a standard bolted flange joint with a gasket, sealing the opening completely. The result is a pressure-tight end closure that holds full system pressure and can be removed when the line needs to be opened for inspection, modification, or future tie-in.

That removability is the practical distinction between a blind flange and a weld cap, which is the other standard method for closing a pipe end. A weld cap closes the pipe permanently without a bolted joint. Reopening it requires cutting the cap off and re-welding. A blind flange closes the pipe with a bolted connection that can be broken and remade any number of times without altering the pipe. For any location where future access is possible or planned, blind flanges are the correct end closure specification.

Pressure load across the face is the mechanical design consideration that makes blind flange thickness important. A blind flange under internal system pressure behaves structurally like a circular plate with uniform load. The larger the bore size and the higher the pressure, the greater the bending stress across the face. ASME B16.5 blind flange dimensions are calculated to handle those stresses within acceptable limits for each pressure class and size combination, which is why a class 1500 blind flange of a given size is considerably thicker and heavier than a class 150 blind of the same nominal size.

Hydrostatic testing is one of the most consistent applications for blind flanges in new construction. Before a piping system is commissioned, it's pressure-tested with water at a test pressure above the design pressure to verify the integrity of all welds and connections. Blind flanges close the open ends of the test section, containing the test pressure. After testing, the blinds are removed and replaced with the permanent connections as commissioning progresses.

Future tie-in provisions are common in plant design. A process expansion that will be added in a future phase may have its pipe stub prepared and installed in the current construction phase, closed with a blind flange until the expansion is ready. That provision avoids breaking into the operating system for the future connection, which would require a shutdown and a hot tap or line stop. The blind flange holds the system closed during the interim period and is removed when the expansion is connected.

Blind flanges are available with full material certification to ASTM, ASME, API, and applicable specifications including NACE MR0175/ISO 15156 for sour service and low-temperature impact testing where required. Contact PM Industries for material selection, pressure class, face type, pipe size, and pricing.

Specification Blind Flange

Standards	ANSI/ASME B16.5, B16.48, GOST, DIN, EN-1092, B16.47 Series A & B, AWWA, BS Flanges
JIS Standard	5K, 10K, 16K, 20K, 30K, 40K, 63K
DIN Flanges	DIN 2527, 2627, 2631, 2656, 2576, 2673, 2629, 2628, 2566

Flanges are Available in Following Materials

Stainless Steel	SS 201, SS 202, SS 301, SS 304, SS 304L, SS 310, SS 310S, SS 316L, SS 316TI, SS 317, SS 317L, SS 321, SS 347, SS 409, SS 409M, SS 409L, SS 410, SS 410S, SS 420, SS 430, SS 431, SS 441, SS 444, SS 446, SS 17-4PH, SS 904L.
Duplex Steel	UNS S32205, UNS S31803 Flange
Super Duplex Steel	UNS S32750, UNS S32760 Flanges
Carbon Steel	Carbon steel A105 Flanges, A36 Flanges, IS 2062 Flanges, A350 LF2 Flanges, F42 Flanges, F52 Flanges, F56 Flanges, F60 Flanges, F65 Flanges, F70 Flanges, F80 Flanges, IBR flanges, A694 Flanges, SS400, SF440, ST37-2 Flanges, S235JrG2 Flanges, P250GH Flanges, C22.8 Flanges, etc.
Alloys Steel	Alloy 20, F1, F5, F9, F11, F22, F91 Flanges
Copper Alloys	Cu-Ni 70/30, Cu-Ni 90/10, C 24000, C 75700, C 51100, C 22000, C 27200, C 21000, C 26800, C 52100, C 77000, C 52000, C 11000, C 74500, C 23000, C 28000, C 12200, C 76400, C 51900, C 75400, C 26000, C 51000, C 10200, C 27000
Nickel Alloys	Nickel 200, 201
Inconel	Inconel 600, 601, 625, 718, 800, 825, X-750
Monel	Monel 400, k500
Hastelloy	Hastelloy C-22, C-276, C-4, X
Titanium	Grade 1, 4, 5(Ti 6Al-4V), 6(Ti 5Al-2.5Sn), 7, 11, 6Al-2Sn-4Zr-2Mo, Grade 12, 6Al-6V-25n, Grade 23(Ti 6AL-4V ELI), 8Ai-1Mo-1V, Grade 5 ELI, Grade 9(3Al-2.5V), 6Al-7Nb.
Aluminium	6063, 1100, 6082 A96082, 1050, 2017, 2024 A92024, 7050 A97050, 5083 A95083, 2014A A92014, 2011 A92011, 6061 A96061 A86061, 5754, 7085, 2050, 7071 7020, 7178, 5052 A95052, 7150, 7075 A97075 A87075, 7575, 2219, 7175
Pressure Rating	Class 150 LBS, 300 LBS, 600 LBS, 900 LBS, 1500 LBS, 2500 LBS
Types	Threaded, Plate, Screwed, Forged.
Supporting material	Gasket, Ring Joint, Flange Bolts
Size range	1/2" (15 NB) to 48" (1200NB) DN10~DN5000
High Temperature	Above 200°C (400°F) For Class 150 Or Above 400°C (750°F)
Low Temperature	Above -29 Degree C (−20°F)
Production technique	Forged, machined and Heat treated
Custom design	As per your drawing
Origin	Indian / USA / Korean / West Europe / Japan
Pressure Class	PN 6 TO PN 100
Coating/Surface Treatment:	Zinc Plated, Anti-rust Paint, Oil Black Paint, Yellow Transparent, Cold and Hot Dip Galvanized.
European/African/Russian Standard Flanges	Available
Test	Direct-reading Spectrograph, X-ray detector, UItrasonic flaw detector, Magnetic particle detector, Hydrostatic testing machine.
Marking Standard	Name of Manufacturer
	Schedule
	Type of Flange Facing
	Pressure Class
	Nominal Pipe Size, etc
Test Certificates	EN 10204/3.1B, NACE MR0103, NACE MR0175
	Raw Materials Certificate
	100% Radiography Test Report
	Third Party Inspection Report, etc

SS Blind Flange Weight

Pipe sizes in Inches	150 LBS			300 LBS			600 LBS			900 LBS			1500 LBS			2500 LBS
	Weld neck	Slip on	Blind	Weld neck	Slip on	Blind	Weld neck	Slip on	Blind	Weld neck	Slip on	Blind	Weld neck	Slip on	Blind	Weld neck	Slip on	Blind
1/2	2	1	1	2	1	1	2	2	2	See 1500 LBS Weight			5	4	4	7	7	7
3/4	2	2	2	3	3	3	4	3	3	See 1500 LBS Weight			6	5	6	8	8	8
1	3	2	2	4	3	3	4	4	4	See 1500 LBS Weight			9	8	8	12	11	11
1 1/2	4	3	3	7	6	6	8	7	8	See 1500 LBS Weight			13	12	13	25	22	23
2	6	5	5	9	7	8	12	9	10	See 1500 LBS Weight			25	25	25	42	37	39
2 1/2	8	7	7	12	10	12	18	13	15	See 1500 LBS Weight			36	36	35	52	55	56
4	15	13	17	25	22	27	42	37	41	53	53	54	73	73	73	145	125	130
5	19	15	20	32	28	35	68	63	68	86	83	87	130	130	140	245	210	225
6	24	19	26	42	39	50	81	80	86	110	110	115	165	165	160	380	325	345
3	10	8	9	15	13	16	23	16	20	31	26	29	48	48	48	94	83	86
8	39	30	45	67	58	81	120	115	140	175	170	200	275	260	300	580	485	530
10	52	43	70	91	81	124	190	170	230	260	245	290	455	435	510	1075	930	1025
22	225	185	355	465	370	640	720	590	1000	NA	NA	NA	NA	NA	NA	NA	NA	NA
14	110	90	140	180	165	250	280	230	355	400	400	520	940	NA	975	NA	NA	NA
16	140	98	180	250	190	295	390	330	495	495	425	600	1250	NA	1300	NA	NA	NA
18	150	130	220	320	250	395	475	400	630	680	600	850	1625	NA	1750	NA	NA	NA
12	80	64	110	140	115	185	225	200	295	325	325	415	690	580	690	1525	1100	1300
20	180	165	285	400	315	505	590	510	810	830	730	1075	2050	NA	2225	NA	NA	NA
24	260	220	430	580	475	790	830	730	1250	1500	1400	2025	3325	NA	3625	NA	NA	NA

Pressure Rating Of Stainless Steel BLRF Flange

Temprature -29 °C	Class 150	Class 300	Class 400	Class 600	Class 900	Class 1500	Class 2500
300	10.2	39.8	53.1	79.6	119.5	199.1	331.8
50	19.2	50.1	66.8	100.2	150.4	250.6	417.7
100	17.7	46.6	62.1	93.2	139.8	233	388.3
150	15.8	45.1	60.1	90.2	135.2	225.4	375.6
38	19.6	51.1	68.1	102.1	153.2	255.3	425.5
200	13.8	43.8	58.4	87.6	131.4	219	365
250	12.1	41.9	55.9	83.9	125.8	209.7	349.5
325	9.3	38.7	51.6	77.4	116.1	193.6	322.6
450	4.6	23	30.7	46	69	115	191.7
350	8.4	37.6	50.1	75.1	112.7	187.8	313
538	1.4	5.9	7.9	11.8	17.7	29.5	49.2
375	7.4	36.4	48.5	72.7	109.1	181.8	303.1
400	6.5	34.7	46.3	69.4	104.2	173.6	289.3
425	5.5	28.8	38.4	57.5	86.3	143.8	239.7
475	3.7	17.4	23.2	34.9	52.3	87.2	145.3
500	2.8	11.8	15.7	23.5	35.3	58.8	97.9

150# Blind Flange Dimensions

Size in Inch	Size in mm	Outer Diameter	Flange Thickness	Raised Face Diameter	Raised Face Height	PCD	No of Bolts	Bolt Size UNC	Machine Bolt Length	RF Stud Length	Hole Size	ISO Stud Size	Weight in kg
		A	B	C	D	E
3/4	20	100	11.2	42.9	2	69.9	4	1/2	50	65	5/8	M14	0.9
1	25	110	12.7	50.8	2	79.4	4	1/2	55	65	5/8	M14	0.9
1 1/4	32	115	14.3	63.5	2	88.9	4	1/2	55	70	5/8	M14	1.4
1 1/2	40	125	15.9	73	2	98.4	4	1/2	65	70	5/8	M14	1.8
1/2	15	90	9.6	34.9	2	60.3	4	1/2	50	55	5/8	M14	0.9
2	50	150	17.5	92.1	2	120.7	4	5/8	70	85	3/4	M16	2.3
3 1/2	90	215	22.3	139.7	2	177.8	8	5/8	75	90	3/4	M16	5.9
2 1/2	65	180	20.7	104.8	2	139.7	4	5/8	75	90	3/4	M16	3.2
3	80	190	22.3	127	2	152.4	4	5/8	75	90	3/4	M16	4.1
4	100	230	22.3	157.2	2	190.5	8	5/8	75	90	3/4	M16	7.7
5	125	255	22.3	185.7	2	215.9	8	3/4	85	95	7/8	M20	9.1
24	600	815	46.1	692.2	2	749.3	20	1 1/4	150	170	1 3/8	M33	196
6	150	280	23.9	215.9	2	241.3	8	3/4	85	100	7/8	M20	11.8
8	200	345	27	269.9	2	298.5	8	3/4	90	110	7/8	M20	20.5
10	250	405	28.6	323.8	2	362	12	7/8	100	115	1	M24	32
12	300	485	30.2	381	2	431.8	12	7/8	100	120	1	M24	50
14	350	535	33.4	412.8	2	476.3	12	1	115	135	1 1/8	M27	64
18	450	635	38.1	533.4	2	577.9	16	1 1/8	125	145	1 1/4	M30	100
20	500	700	41.3	584.2	2	635	20	1 1/8	140	160	1 1/4	M30	130
16	400	595	35	469.9	2	539.8	16	1	115	135	1 1/8	M27	82

BLRF Flange Dimensions Class 300

Size in Inch	Size in MM	Outer Diameter	Flange Thickness	RF Diameter	RF Height	PCD	No of Bolts	Bolt Size UNC	Machine Bolt Length	RF Stud Length	Hole Size	ISO Stud Size	Weight in kg
		A	B	C	D	E
1/2	15	95	12.7	34.9	2	66.7	4	1/2	55	65	5/8	M14	1.4
3/4	20	115	14.3	42.9	2	82.6	4	5/8	65	75	3/4	M16	1.4
1	25	125	15.9	50.8	2	88.9	4	5/8	65	75	3/4	M16	1.4
1 1/4	32	135	17.5	63.5	2	98.4	4	5/8	70	85	3/4	M16	1.8
1 1/2	40	155	19.1	73	2	114.3	4	3/4	75	90	7/8	M20	2.7
2	50	165	20.7	92.1	2	127	8	5/8	75	90	3/4	M16	3.7
2 1/2	65	190	23.9	104.8	2	149.2	8	3/4	85	100	7/8	M20	5.5
10	250	445	46.1	323.8	2	387.4	16	1	140	160	1 1/8	M27	57
3 1/2	90	230	28.6	139.7	2	184.2	8	3/4	95	110	7/8	M20	9.6
4	100	255	30.2	157.2	2	200	8	3/4	95	115	7/8	M20	12.3
5	125	280	33.4	185.7	2	235	8	3/4	110	120	7/8	M20	15.9
6	150	320	35	215.9	2	269.9	12	3/4	110	120	7/8	M20	22.7
8	200	380	39.7	269.9	2	330.2	12	7/8	120	140	1	M24	36
24	600	915	68.3	692.2	2	812.8	24	1 1/2	205	230	1 5/8	M39	359
12	300	520	49.3	381	2	450.8	16	1 1/8	145	170	1 1/4	M30	84
3	80	210	27	127	2	168.3	8	3/4	90	110	7/8	M20	7.3
14	350	585	52.4	412.8	2	514.4	20	1 1/8	160	180	1 1/4	M30	113
16	400	650	55.6	469.9	2	571.5	20	1 1/4	165	190	1 3/8	M33	134
18	450	710	58.8	533.4	2	628.6	24	1 1/4	170	195	1 3/8	M33	181
20	500	775	62	584.2	2	685.8	24	1 1/4	185	205	1 3/8	M33	230

Asme B16 5 BLRF Flange Dimensions class 400

Size in Inch	Size in MM	Outer Diameter	Flange Thickness	RF Diameter	RF Height	PCD	No of Bolts	Bolt Size UNC	RF Stud Length	Hole Size	ISO Stud Size	Weight in kg
		A	B	C	D	E
10	250	445	54	323.8	7	387.4	16	1 1/8	190	1 1/4	M30	71
3/4	20	115	15.9	42.9	7	82.6	4	5/8	90	3/4	M16	1.5
1	25	125	17.5	50.8	7	88.9	4	5/8	90	3/4	M16	1.8
1 1/4	32	135	20.7	63.5	7	98.4	4	5/8	95	3/4	M16	2.3
1 1/2	40	155	22.3	73	7	114.3	4	3/4	110	7/8	M20	3.7
1/2	15	95	14.3	34.9	7	66.7	4	1/2	75	5/8	M14	1.5
2	50	165	25.4	92.1	7	127	8	5/8	110	3/4	M16	4.6
2 1/2	65	190	28.6	104.8	7	149.2	8	3/4	120	7/8	M20	6.8
3 1/2	90	230	35	N/A	7	184.2	8	7/8	140	1	M24	13.2
4	100	255	35	157.2	7	200	8	7/8	140	1	M24	15
5	125	280	38.1	185.7	7	235	8	7/8	145	1	M24	20
3	80	210	31.8	127	7	168.3	8	3/4	125	7/8	M20	9.1
14	350	585	60.4	412.8	7	514.4	20	1 1/4	210	1 3/8	M33	132
6	150	320	41.3	215.9	7	269.9	12	7/8	150	1	M24	28
8	200	380	47.7	269.9	7	330	12	1	170	1 1/8	M27	46
12	300	520	57.2	381	7	450.8	16	1 1/4	205	1 3/8	M33	102
24	600	915	76.2	692.2	7	812.8	24	1 3/4	265	1 7/8	M45	405
16	400	650	63.5	469.9	7	571.5	20	1 3/8	220	1 1/2	M36	168
20	500	775	69.9	584.2	7	685.8	24	1 1/2	240	1 3/4	M39	266
18	450	710	66.7	533.4	7	628.6	24	1 3/8	230	1 1/2	M36	207

Class 600 Blank Flange Dimensions

Size in Inch	Size in MM	Outer Diameter	Flange Thickness	RF Diameter	RF Height	PCD	No of Bolts	Bolt Size UNC	RF Stud Length	Hole Size	ISO Stud Size	Weight in kg
		A	B	C	D	E
10	250	510	63.5	323.8	7	431.8	16	1 1/4	215	1 3/8	M33	105
3/4	20	115	15.9	42.9	7	82.6	4	5/8	90	3/4	M16	1.4
1	25	125	17.5	50.8	7	88.9	4	5/8	90	3/4	M16	1.8
1 1/4	32	135	20.7	63.5	7	98.4	4	5/8	95	3/4	M16	2.3
1/2	15	95	14.3	34.9	7	66.7	4	1/2	75	5/8	M14	1.4
1 1/2	40	155	22.3	73	7	114.3	4	3/4	110	7/8	M20	3.7
2	50	165	25.4	92.1	7	127	8	5/8	110	3/4	M16	4.6
3	80	210	31.8	127	7	168.3	8	3/4	125	7/8	M20	9.1
3 1/2	90	230	35	N/A	7	184.2	8	7/8	140	1	M24	13.2
4	100	275	38.1	157.2	7	215.9	8	7/8	145	1	M24	18.7
2 1/2	65	190	28.6	104.8	7	149.2	8	3/4	120	7/8	M20	6.8
5	125	330	44.5	185.7	7	266.7	8	1	165	1 1/8	M27	31
6	150	355	47.7	215.9	7	292.1	12	1	170	1 1/8	M27	39
8	200	420	55.6	269.9	7	349.2	12	1 1/8	190	1 1/4	M30	64
12	300	560	66.7	381	7	489	20	1 1/4	220	1 3/8	M33	134
14	350	605	69.9	412.8	7	527	20	1 3/8	235	1 1/2	M36	161
24	600	940	101.6	692.2	7	838.2	24	1 7/8	330	2	M48	568
16	400	685	76.2	469.9	7	603.2	20	1 1/2	255	1 5/8	M39	225
18	450	745	82.6	533.4	7	654	20	1 5/8	275	1 3/4	M42	286
20	500	815	88.9	584.2	7	723.9	24	1 5/8	285	1 3/4	M42	368

Blind Flange Dimensions Class 900

Size in Inch	Size in mm	Outer Dia.	Flange Thick.	RF Dia.	RF Height	PCD	No of Bolts	Bolt Size UNC	RF Stud Length	Hole Size	ISO Stud Size	Weight in kg
		A	B	C	D	E
1/2	15	120	22.3	34.9	7	82.6	4	3/4	110	7/8	M20	1.8
3/4	20	130	25.4	42.9	7	88.9	4	3/4	115	7/8	M20	2.7
1	25	150	28.6	50.8	7	101.6	4	7/8	125	1	M24	3.6
1 1/4	32	160	28.6	63.5	7	111.1	4	7/8	125	1	M24	4.1
1 1/2	40	180	31.8	73	7	123.8	4	1	140	1 1/8	M27	5.9
2	50	215	38.1	92.1	7	165.1	8	7/8	145	1	M24	10.1
2 1/2	65	245	41.3	104.8	7	190.5	8	1	160	1 1/8	M27	16
3	80	240	38.1	127	7	190.5	8	7/8	145	1	M24	13
4	100	290	44.5	157.2	7	235	8	1 1/8	170	1 1/4	M30	24.5
5	125	350	50.8	185.7	7	279.4	8	1 1/4	190	1 3/8	M33	39.5
6	150	380	55.6	215.9	7	317.5	12	1 1/8	190	1 1/4	M30	53
8	200	470	63.5	269.9	7	393.7	12	1 3/8	220	1 1/2	M36	91
10	250	545	69.9	323.8	7	469.9	16	1 3/8	235	1 1/2	M36	132
12	300	610	79.4	381	7	533.4	20	1 3/8	255	1 1/2	M36	189
14	350	640	85.8	412.8	7	558.8	20	1 1/2	275	1 5/8	M39	237
16	400	705	88.9	469.9	7	616	20	1 5/8	285	1 3/4	M42	273
18	450	785	101.6	533.4	7	685.8	20	1 7/8	325	2	M48	367
20	500	855	108	584.2	7	749.3	20	2	350	2 1/8	M52	463
24	600	1040	139.7	692.2	7	901.7	20	2 1/2	440	2 5/8	M64	875

SS BLRF Flange #1500 Dimensions

Size in Inch	Size in mm	Outer Dia.	Flange Thick.	RF Dia.	RF Height	PCD	No of Bolts	Bolt Size UNC	RF Stud Length	Hole Size	ISO Stud Size	Weight in kg
		A	B	C	D	E
1/2	15	120	22.3	34.9	7	82.6	4	3/4	110	7/8	M20	1.8
3/4	20	130	25.4	42.9	7	88.9	4	3/4	115	7/8	M20	2.7
1	25	150	28.6	50.8	7	101.6	4	7/8	125	1	M24	3.7
1 1/4	32	160	28.6	63.5	7	111.1	4	7/8	125	1	M24	4.1
1 1/2	40	180	31.8	73	7	123.8	4	1	140	1 1/8	M27	5.9
2	50	215	38.1	92.1	7	165.1	8	7/8	145	1	M24	10.1
2 1/2	65	245	41.3	104.8	7	190.5	8	1	160	1 1/8	M27	15.9
3	80	265	47.7	127	7	203.2	8	1 1/8	180	1 1/4	M30	21.8
4	100	310	54	157.2	7	241.3	8	1 1/4	195	1 3/8	M33	33
5	125	375	73.1	185.7	7	292.1	8	1 1/2	250	1 5/8	M39	64
6	150	395	82.6	215.9	7	317.5	12	1 3/8	260	1 1/2	M36	75
8	200	485	92.1	269.9	7	393.7	12	1 5/8	290	1 3/4	M42	136
10	250	585	108	323.8	7	482.6	12	1 7/8	335	2	M48	232
12	300	675	123.9	381	7	571.5	16	2	375	2 1/8	M52	314
14	350	750	133.4	412.8	7	635	16	2 1/4	405	2 3/8	M56	443
16	400	825	146.1	469.9	7	704.8	16	2 1/2	445	2 5/8	M64	591
18	450	915	162	533.4	7	774.7	16	2 3/4	495	2 7/8	M72	795
20	500	985	177.8	584.2	7	831.8	16	3	540	3 1/8	M76	1022
24	600	1170	203.2	692.2	7	990.6	16	3 1/2	615	3 5/8	M90	1648

B16.47 Series B Blind Flange Dimensions Class 2500

Size in Inch	Size in mm	Outer Dia.	Flange Thick.	RF Dia.	RF Height	PCD	No of Bolts	Bolt Size UNC	RF Stud Length	Hole Size	ISO Stud Size	Weight in kg
		A	B	C	D	E
1/2	15	135	30.2	34.9	7	88.9	4	3/4	120	7/8	M20	3.2
3/4	20	140	31.8	42.9	7	95.2	4	3/4	125	7/8	M20	3.7
1	25	160	35	50.8	7	108	4	7/8	140	1	M24	5
1 1/4	32	185	38.1	63.5	7	130.2	4	1	150	1 1/8	M27	7.8
1 1/2	40	205	44.5	73	7	146	4	1 1/8	170	1 1/4	M30	10.5
2	50	235	50.9	92.1	7	171.4	8	1	180	1 1/8	M27	18
2 1/2	65	265	57.2	104.8	7	196.8	8	1 1/8	195	1 1/4	M30	25.5
3	80	305	66.7	127	7	228.6	8	1 1/4	220	1 3/8	M33	39
4	100	355	76.2	157.2	7	273	8	1 1/2	255	1 5/8	M39	61.5
5	125	420	92.1	185.7	7	323.8	8	1 3/4	300	1 7/8	M45	102
6	150	485	108	215.9	7	368.3	8	2	345	2 1/8	M52	157
8	200	550	127	269.9	7	438.2	12	2	380	2 1/8	M52	241
10	250	675	165.1	323.8	7	539.8	12	2 1/2	490	2 5/8	M64	470
12	300	760	184.2	381	7	619.1	12	2 3/4	540	2 7/8	M72	575