Blind Flange

Approx Price:

Category: , Flanges

Size : 1/2″ (15 NB) to 48″ (1200NB)
Standards : ANSI B16.5, ANSI B16.47 Series A & B, MSS SP44, ASA, API-605, AWWA
Pressure Ratings : Class 150, Class 300, Class 400, Class 600, Class 900, Class1500, Class 2500 | PN6, PN10, PN16, PN25, PN40, PN64 etc.
Stainless Steel Blind Flanges : ASTM A182 F202, F304/304L/304H, F316/316L, F316H, F316TI, F310, F321, F904L
Alloy Steel Blind Flanges: ASTM A182 F1, F5, F9, F11, F22, F91
Special Alloy Blind Flanges : Duplex, Super Duplex, Nickel Alloys
Flange Face Type : Flate Face (FF), Raised Face (RF), Ring Type Joint (RTJ)

Blind flanges are an essential component in piping systems, designed to seal off the ends of pipes, valves, or pressure vessel openings. These flanges play a critical role in industries such as oil and gas, petrochemicals, power generation, water treatment, and construction. In this comprehensive guide, we will explore everything you need to know about blind flanges, including their specifications, materials, applications, and benefits.

What are Blind Flanges?

A blind flange is a solid disk-shaped component used to block the end of a piping system or vessel. Unlike other types of flanges, blind flanges do not have a central bore, making them ideal for isolating sections of a pipeline or terminating a flow. Blind flanges are manufactured to meet various pressure ratings and material standards, ensuring reliability in even the most demanding environments.

Applications of Blind Flanges

Blind flanges are used across various industries for applications such as:
Pipeline Isolation: Sealing off pipeline ends during maintenance or system testing.
Pressure Testing: Ensuring pipelines can handle designated pressure levels by blocking one end.
Flow Termination: Closing the end of pipes or pressure vessels in permanent or temporary setups.
Safety Measures: Preventing leakage or spillage in hazardous environments.
Inspection and Cleaning: Allowing easy access to pipeline interiors by removing the blind flange.

Industries that frequently use blind flanges include:

Oil & Gas
Petrochemicals
Pharmaceuticals
Food Processing
Water Treatment
Power Generation
Construction

Technical Specifications of Blind Flanges
Size Range	Our blind flanges are available in sizes ranging from 1/2″ (15 NB) to 48″ (1200 NB), catering to a wide variety of industrial applications.
Standards Compliance	We manufacture blind flanges conforming to the following international standards: ANSI B16.5 ANSI B16.47 Series A & B MSS SP44 ASA API-605 AWWA Custom designs based on your specific requirements.
Pressure Ratings	Class Ratings: Class 150, Class 300, Class 400, Class 600, Class 900, Class 1500, and Class 2500. PN Ratings: PN6, PN10, PN16, PN25, PN40, PN64,
Materials	Carbon Steel Blind Flanges: Grades: ASTM A105/A105N, A350 LF1, LF2 CL1/CL2, LF3 CL1/CL2, A694 F42–F70, A516 (Grades 60, 65, 70), Steel RST37.2, and C22.8. Specialized designs like Spectacle Blind Flanges, Spacer Rings, and Spade Flanges are also available.
	Stainless Steel Blind Flanges: Grades: ASTM A182 F202, F304/304L/304H, F316/316L, F316H, F316TI, F310, F321, F904L.
	Alloy Steel Blind Flanges: Grades: ASTM A182 F1, F5, F9, F11, F22, F91.
	Special Alloy Blind Flanges: Duplex, Super Duplex, and Nickel Alloys.
Flange Face Types	Flat Face (FF)
	Raised Face (RF)
	Ring Type Joint (RTJ)
Coating/Surface Treatments	Anti-rust Paint Oil Black Paint Yellow Transparent Coating Zinc Plating Cold and Hot Dip Galvanization


Blind Flange Dimensions and Weight Chart
NPS	A	C	G	H	I	J	W
	inch	inch	inch	No. of holes	inch	inch	kg/pc
	mm	mm	mm	No. of holes	mm	mm	kg/pc
1/2	3.500	0.440	1.380	4	0.620	2.380	0.42
1/2	88.90	11.20	35.10	4	15.70	60.45	0.42
3/4	3.880	0.500	1.690	4	0.620	2.750	0.61
3/4	98.60	12.70	42.90	4	15.70	69.85	0.61
1	4.250	0.560	2.000	4	0.620	3.120	0.86
1	108.0	14.20	50.80	4	15.70	79.25	0.86
1-1/4	4.620	0.620	2.500	4	0.620	3.500	1.17
1-1/4	117.3	15.70	63.50	4	15.70	88.90	1.17
1-1/2	5.000	0.690	2.880	4	0.620	3.880	1.53
1-1/2	127.0	17.50	73.15	4	15.70	98.60	1.53
2	6.000	0.750	3.620	4	0.750	4.750	2.42
2	152.4	19.10	91.90	4	19.10	120.7	2.42
2-1/2	7.000	0.880	4.120	4	0.750	5.500	3.94
2-1/2	177.8	22.40	104.6	4	19.10	139.7	3.94
3	7.500	0.940	5.000	4	0.750	6.000	4.93
3	190.5	23.90	127.0	4	19.10	152.4	4.93
3-1/2	8.500	0.940	5.500	8	0.750	7.000	6.17
3-1/2	215.9	23.90	139.7	8	19.10	177.8	6.17
4	9.000	0.940	6.190	8	0.750	7.500	7.00
4	228.6	23.90	157.2	8	19.10	190.5	7.00
5	10.00	0.940	7.310	8	0.880	8.500	8.63
5	254.0	23.90	185.7	8	22.40	215.9	8.63
6	11.00	1.000	8.500	8	0.880	9.500	11.3
6	279.4	25.40	215.9	8	22.40	241.3	11.3
8	13.50	1.120	10.62	8	0.880	11.75	19.6
8	342.9	28.40	269.7	8	22.40	298.5	19.6
10	16.00	1.190	12.75	12	1.000	14.25	28.8
10	406.4	30.20	323.9	12	25.40	362.0	28.8
12	19.00	1.250	15.00	12	1.000	17.00	43.2
12	482.6	31.75	381.0	12	25.40	431.8	43.2
14	21.00	1.380	16.25	12	1.120	18.75	58.1
14	533.4	35.10	412.8	12	28.40	476.3	58.1
16	23.50	1.440	18.50	16	1.120	21.25	76.0
16	596.9	36.60	469.9	16	28.40	539.8	76.0
18	25.00	1.560	21.00	16	1.250	22.75	93.7
18	635.0	39.60	533.4	16	31.75	577.9	93.7
20	27.50	1.690	23.00	20	1.250	25.00	122
20	698.5	42.90	584.2	20	31.75	635.0	122
24	32.00	1.880	27.25	20	1.380	29.50	185
24	812.8	47.80	692.2	20	35.10	749.3	185