ASME/ANSI B16.48 Spectacle Blind Flange

ASME/ANSI B16.48 Spectacle Blind Flange Supplier

A spectacle blind flange, often referred to simply as a "spectacle blind," is a specialized piping component used to seal off a pipeline for maintenance or system isolation. It consists of two metal discs: one solid and one with a hole. The solid disc is used to block the flow of fluid, while the perforated disc can be used when flow is required. The name "spectacle" comes from the shape of the two discs, resembling a pair of spectacles or glasses when viewed from the side. Typically made from materials like carbon steel, stainless steel, or alloy steels, spectacle blind flanges are used in industries such as oil and gas, chemical processing, and water treatment, providing a reliable method of controlling flow and ensuring safety during system shutdowns or maintenance. They are designed to be bolted between two flanges and are available in various pressure ratings and sizes to suit different operational requirements.

Ample Alloys is a trusted supplier known for its commitment to quality, reliability, and exceptional customer service. With a focus on meeting industry standards, We ensures timely deliveries and precise solutions tailored to customer needs. Our attention to detail and technical expertise have earned them a strong reputation as a dependable partner in the metal industry.

High-Pressure Spectacle Blind Flange, ANSI Spectacle Blind Flange, Forged Spectacle Blind Flange, Piping Isolation Flange, Blind Flange with Hole, Carbon Steel, Stainless Steel Spectacle Blind Flange, Perforated Spectacle Blind Flange

Spectacle Blind Flange

Size Range

15mm ( 1/2" NPS ) up to 600mm ( 24" NPS ), For 2500# in sizes from NPS 1/2 to NPS 12

Flange Face Type

FF—Flat Face, RF—Raised Face, FM—Female Face, M—Male Face, T—Tongue Face, G—Groove Face, RJ—Ring Joint.

Stainless Steel

ASTM A182 F 304, 304L, 304H, 316, 316L, 316H, 317, 317L, 321, 321H, 310, 310S, 347, 904L, etc.

Standards / Dimension

ANSI/ASME B16.48, BS4504, BS 10, EN-1092, DIN

Carbon Steel

ASTM A105/A105N (SA105N), LTCS A350 LF2, A694

Alloy Steel

ASTM A182 / SA182 - F1 / F5 / F9 / F11 / F12 / F22 / F91

Pressure Class

150#, 300#, 600#, 900#, 1500#, 2500#, PN6, PN10, PN16, PN25, PN40, PN64.

Duplex & Super Duplex

ASTM A182 / ASME SA182 - S31803, S32205, 2205, S32750, S32760, S32950, 2507.

MTC

EN 10204 3.2 and EN 10204 3.1, Test Certificates certifying NACE MR0175, NACE MR0103

ASME B16.48 Spectacle Blind Flange Dimensions

ASME B16.48 Spectacle Blind Flange (Class 150) - Dimensions & Weight

NPS	Outside Ø A	Inside Ø B	Center Line C	THK t	Web Width W
1/2	45	16	60	3	38
3/4	54	21	70	3	38
1	64	27	80	3	38
1.1/4	73	42	90	6.4	38
1.1/2	83	48	100	6.4	38
2	102	61	120	6.4	51
2.1/2	107	73	140	6.4	51
3	133	89	150	6.4	64
3.1/2	159	102	175	9.7	64
4	172	114	190	9.7	64
5	194	141	215	9.7	76
6	219	168	240	12.7	76
8	276	219	300	12.7	76
10	337	273	360	15.7	102
12	406	324	430	19.1	102
14	448	356	475	19.1	108
16	511	406	460	22.4	108
18	546	457	580	25.4	114
20	603	508	635	28.4	121
24	714	610	750	31.8	140

ASME B16.48 Spectacle Blind Flange (Class 300) - Dimensions & Weight

NPS	Outside Ø A	Inside Ø B	Center Line C	THK t	Web Width W
1/2	51	16	65	6.4	38
3/4	64	21	80	6.4	38
1	70	27	90	6.4	38
1.1/4	79	42	100	6.4	38
1.1/2	92	48	115	6.4	38
2	108	61	125	9.7	51
2.1/2	127	73	150	9.7	51
3	146	89	170	9.7	64
3.1/2	162	102	185	12.7	64
4	178	114	200	12.7	64
5	213	141	235	15.7	76
6	248	168	270	15.7	76
8	305	219	330	22.4	76
10	359	273	385	25.4	102
12	419	324	450	28.4	102
14	483	356	515	31.8	108
16	536	406	570	38.1	108
18	594	457	630	41.1	114
20	651	508	685	44.5	121
24	772	610	810	50.8	140

ASME B16.48 Spectacle Blind Flange (Class 600) - Dimensions & Weight

NPS	Outside Ø A	Inside Ø B	Center Line C	THK t	Web Width W
1/2	51	16	65	6.4	38
3/4	64	21	80	6.4	38
1	70	27	90	6.4	57
1.1/4	79	37	100	9.7	57
1.1/2	92	43	115	9.7	67
2	108	55	125	9.7	57
2.1/2	127	67	150	12.7	67
3	146	83	170	12.7	67
3.1/2	159	96	185	15.7	76
4	191	108	215	15.7	76
5	238	135	265	19.1	86
6	264	162	290	22.4	86
8	318	212	350	28.4	95
10	397	265	430	35.1	105
12	454	315	490	41.1	105
14	489	346	525	44.5	114
16	562	397	605	50.8	124
18	610	448	655	53.8	133
20	679	497	725	63.5	133
24	787	597	840	73.2	152

ASME B16.48 Spectacle Blind Flange (Class 900) - Dimensions & Weight

NPS	Outside Ø A	Inside Ø B	Center Line C	THK t	Web Width W
1/2	60	16	80	6.4	38
3/4	67	21	90	6.4	41
1	76	27	100	6.4	57
1.1/4	86	37	110	9.7	57
1.1/2	95	43	125	9.7	67
2	140	55	165	12.7	57
2.1/2	162	67	190	12.7	67
3	165	83	190	15.7	67
4	203	108	235	19.1	76
5	244	135	280	22.4	86
6	286	162	320	25.4	86
8	356	212	395	35.1	95
10	432	265	470	41.1	105
12	495	315	535	47.8	105
14	518	346	560	53.8	114
16	572	397	615	60.5	124
18	635	448	685	66.5	133
20	696	497	750	73.2	133
24	835	597	900	88.9	152

ASME B16.48 Spectacle Blind Flange (Class 1500) - Dimensions & Weight

NPS	Outside Ø A	Inside Ø B	Center Line C	THK t	Web Width W
1/2	61	16	80	6.4	38
3/4	67	21	90	9.7	41
1	76	27	100	9.7	64
1.1/4	86	35	110	9.7	64
1.1/2	95	41	125	12.7	70
2	140	53	165	12.7	70
2.1/2	162	63	190	15.7	76
3	172	78	205	19.1	76
4	206	102	240	22.4	89
5	251	128	290	28.4	89
6	279	154	320	35.1	89
8	349	203	395	41.1	102
10	432	255	480	50.8	114
12	518	303	570	60.5	114
14	575	333	635	66.5	127
16	638	381	705	76.2	133
18	702	429	775	85.9	146
20	752	478	830	95.3	152
24	899	575	990	111.3	178

ASME B16.48 Spectacle Blind Flange (Class 2500) - Dimensions & Weight

NPS	Outside Ø A	Inside Ø B	Center Line C	THK t	Web Width W
1/2	67	16	90	9.7	38
3/4	73	21	95	9.7	41
1	83	27	110	9.7	64
1.1/4	102	35	130	12.7	64
1.1/2	114	41	145	15.7	70
2	143	53	170	15.7	70
2.1/2	165	63	195	19.1	76
3	194	78	230	22.4	76
4	232	102	275	28.4	89
5	276	128	325	35.1	89
6	314	154	370	41.1	89
8	384	198	440	53.8	102
10	473	248	540	66.5	114
12	546	289	620	79.2	114

Blind Spectacle Flange Standards

The standards for blind spectacle flanges ensure that these components meet the necessary requirements for performance, safety, and compatibility in piping systems. Some key standards for blind spectacle flanges include:

ASME/ANSI Standards (American):
- ASME B16.5 – Pipe Flanges and Flanged Fittings (NPS 1/2" to 24").
- ASME B16.47 – Large Diameter Steel Flanges (Series A & B, NPS 26" to 60").
- ASME B16.36 – Orifice Flanges.
- ASME B16.48 – Line Blanks (Spectacle, Spade, and Spacer Flanges).
- ANSI B16.1 – Cast Iron Flanges and Flanged Fittings.
- ANSI B16.42 – Ductile Iron Pipe Flanges and Flanged Fittings.
ISO Standards (International)
- ISO 7005-1 – Steel Flanges for General Applications.
- ISO 7005-2 – Cast Iron Flanges.
- ISO 7005-3 – Copper Alloy Flanges.
EN Standards (European)
- EN 1092-1 – Steel Flanges.
- EN 1092-2 – Cast Iron Flanges.
- EN 1092-3 – Copper Alloy Flanges.
- EN 1092-4 – Aluminium Alloy Flanges.
DIN Standards (German)
- DIN 2527 – Blind Flanges.
- DIN 2576 – Slip-On Flanges (PN 10).
- DIN 2633 – Weld Neck Flanges (PN 16).
- DIN 2634 – Weld Neck Flanges (PN 25).
- DIN 2635 – Weld Neck Flanges (PN 40).
JIS Standards (Japanese)
- JIS B2220 – Steel Pipe Flanges.
GOST Standards (Russian)
- GOST 12820 – Flat Flanges for Steel Pipe Joints.
- GOST 12821 – Steel Welded Flanges for High-Pressure Applications.
- GOST 33259 – Flange Connections for Industrial Equipment and Pipelines.
BS Standards (British)
- BS 4504 – Circular Flanges for Pipes, Valves, and Fittings.
- BS 10 – Specification for Flanges and Bolting.
API Standards (Oil & Gas)
- API 6A – Wellhead and Christmas Tree Equipment Flanges.
- API 605 – Large-Diameter Carbon Steel Flanges (merged into ASME B16.47 Series B).
AWWA Standards (Waterworks)
- AWWA C207 – Steel Ring Flanges for Waterworks Service.
MSS Standards (Manufacturer's Standardization Society)
- MSS SP-44 – Steel Pipe Flanges (merged into ASME B16.47 Series A).
- MSS SP-51 – Flanges for Glass-Lined Equipment.
Material-Specific Standards (ASTM)
- ASTM A105 – Carbon Steel Forged Flanges.
- ASTM A182 – Alloy and Stainless Steel Forged Flanges.
- ASTM A350 – Carbon and Low-Alloy Steel Flanges for Low-Temperature Service.
- ASTM A694 – High-Strength Carbon and Alloy Steel Flanges for High-Pressure Applications.
Other Regional and Specialized Standards
- KS B1511 – Korean Standard Flanges.
- NF E29-206 – French Standard Flanges.
- SANS 1123 – South African Standard for Steel Flanges.

Why Ample Alloys For Spectacle Blind Flange!

Ample Alloys provides competitive pricing, on-time delivery, and exceptional after-sales support, making it the preferred choice for high-quality Spectacle Blind Flanges worldwide.

High-Quality Products

Ensures durable and precisely engineered spectacle blind flanges.

Industry Standards Compliance

Meets the highest standards for performance and reliability.

Strict Quality Control

Adheres to rigorous quality control processes to deliver top-tier products.

Technical Expertise

Provides expert guidance and support for selecting the right spectacle blind flange.

What is the purpose of a spectacle blind flange?

The main purpose of a spectacle blind flange is to isolate a section of the piping system for maintenance, inspection, or safety purposes. The solid disc blocks flow, while the perforated disc allows flow when required.

What is the difference between a spectacle blind flange and a regular blind flange?

A regular blind flange is a solid disc used to seal off the end of a pipe, while a spectacle blind flange consists of two discs (solid and perforated) that can either isolate or allow flow in a piping system depending on the configuration.

What are the advantages of using a spectacle blind flange?

Spectacle blind flanges provide a cost-effective and efficient way to isolate or allow flow in a piping system. They are reusable, reduce downtime, and eliminate the need for additional maintenance work, making them ideal for temporary or periodic shutdowns.