What Is EN 1092-1 Type 05 Flange?

In modern industry, pipeline design is of critical importance, and flanges, as essential connecting components, are widely used in pipeline systems, particularly in high-demand industries such as petroleum, chemicals, power, and aerospace. The EN 1092-1 Type 05 flange, commonly referred to as a blind flange, is a key flange type that, thanks to its robust structure and reliable performance, has become a preferred choice across numerous industrial sectors.

ZIZI specializes in producing flanges of various materials and types, strictly adhering to international standards (such as EN 1092-1), providing high-quality pipe connection solutions for customers worldwide.

EN 1092-1 Type 05 Flange Overview:

EN 1092-1 Type 05 flange, commonly referred to as blind flange (BL), is a special type of flange frequently used in piping systems. Unlike other flanges, blind flanges are solid circular discs without a central hole, designed to seal open ends of pipes. They are typically installed at the end of a pipe to temporarily or permanently seal it, preventing fluid or gas leakage and protecting the pipe from external environmental influences. Blind flanges have high requirements for sealing gaskets and typically use raised face (RF) sealing surfaces to ensure reliable sealing performance.

Material Selection for Blind Flanges：

Carbon Steel	ASTM A105/A105N
low temperature steel	ASTM A350 LF2/LF3
Pipeline steel	ASTM A694 F42/46/52/56/65/70
Alloy steel	ASTM A182 F5/F9/F11/F12/F22/F91/F92
Stainless steel	ASTM A182 F304/304L/304H、F316/316L、F317、F310S、F321、F347、F904L
Duplex stainless steel	ASTM A182 F51/53/55/60

EN 1092 Type 05 Flange Dimension:

EN 1092-1 blind flanges are mainly applicable to nominal pressures ranging from PN2.5 to PN400 and nominal sizes from DN10 to DN4000. The figure below shows the dimensions for PN16 and DN10-DN350.

DN	Mating dimensions					Flange thickness	Centre portion
	Outside diameter	Diameter of bolt circle	Diameter of bolt hole	Bolting
	D	K	L	Number	Size	C4	Gmax
10	90	60	14	4	M12	16	–
15	95	65	14	4	M12	16	–
20	105	75	14	4	M12	18	–
25	115	85	14	4	M12	18	–
32	140	100	18	4	M16	18	–
40	150	110	18	4	M16	18	–
50	165	125	18	4	M16	18	–
65	185	145	18	86	M16	18	55
80	200	160	18	8	M16	20	70
100	220	180	18	8	M16	20	90
125	250	210	18	8	M16	22	115
150	285	240	22	8	M20	22	140
200	340	295	22	12	M20	24	190
250	405	355	26	12	M24	26	235
300	460	410	26	12	M24	28	285
350	520	470	26	16	M24	30	330

Flange facing dimensions:

The above data is sourced from: en-1092-1-2018-flanges.

EN 1092-1 Type 05 Flange Advantages:

✅Reliable sealing – The solid disc ensures the sealing at the end of the pipe

✅Easy to maintain – Quick installation and disassembly without the need to cut pipes, facilitating inspection and isolation

✅A variety of materials are available – carbon steel, stainless steel, alloy steel, and other materials

✅Standard compatibility – Complies with international standards such as EN 1092-1

✅High cost performance – simple and reliable structure, long service life, and low maintenance cost

✅Safe and reliable – Through high-voltage testing, it can ensure the safety of industrial operation

Application Areas:

•Petrochemical industry

•Natural gas pipelines

•Electric power industry

•Water treatment systems

•Shipbuilding industry

•Metallurgical industry

30 7 月, 2025