UNI Flanges

Understanding your choice of UNI flanges options

UNI flanges are widely used in Europe, particularly in Italy. They come in several different options, which are suitable for various applications. Here are some of the most common options:

If you’re in the market for high-quality flanges，we offer a wide variety of flanges to suit your needs, including the popular UNI 2276, UNI 2277, UNI 2278, UNI 6080, UNI 6081, UNI 6082, UNI 6083, UNI 6084, UNI 6091, UNI 6092, UNI 6093, UNI 6094, UNI 6095, UNI 2253, UNI 2254, UNI 6088, UNI 6089, and UNI 6090 flanges.

When choosing UNI flanges, it’s important to consider the application and the pressure requirements. It’s also important to make sure that the flanges are compatible with the pipes and fittings being used.

What are UNI flanges?

In pipeline and piping systems, UNI flanges are commonly used. The term “UNI” originates from “Unione Italiana,” meaning “Italian Union,” and these flanges are frequently used in Italy and other parts of Europe.
UNI flanges are a type of flange designed to connect two sections of pipe or equipment. They usually have a round shape with bolt holes around the edge to secure the flange to the adjacent section. The bolt holes are typically arranged in a circle and can be drilled or tapped. Uni flanges are available in various sizes and pressure ratings for multiple applications.
A distinctive feature of UNI flanges is their face-to-face dimensions. These dimensions are specific to UNI flanges and are used to ensure that the flanges can be connected appropriately. The face-to-face dimensions of UNI flanges are typically larger than other flanges and require more installation space. However, this larger size can make them more stable and durable than different flange types.

What are the different types of UNI flanges?

Flanges come in many different types and styles, but some common types of UNI flanges include:

Types of UNI flanges

The United Nations International (UNI) standard for flanges is widely recognized and used in many industries worldwide. UNI flanges come in different types, each with unique characteristics and applications. We introduce you to the most common types of UNI flanges, including weld neck flanges, Threaded flanges, Flat flanges, Lap joint flanges, Blind flanges, and Slip-on flanges.

1. Weld neck flanges are widely used in high-pressure applications. The weld neck flange is designed to be welded to a pipe‘s end, which creates a smooth and robust connection that can withstand high pressure. This flange type is ideal for applications where the pipeline must withstand high temperatures, such as in the oil and gas industry.

2. Threaded flanges are similar to weld neck flanges, but instead of being welded to the end of the pipe, they are screwed onto the pipe’s end. Threaded flanges are used for low-pressure applications and are easy to install and maintain. These flanges are commonly used in plumbing and small-scale industrial applications.

3. Flat flanges, also known as plate flanges, are flat and thin, making them ideal for low-pressure applications where space is limited. They are easy to install and maintain and are commonly used in small-scale piping systems.

4. Lap joint flanges are designed to be used with a lap joint stub end. The loose flange slides over the stub end and is bolted to the flange on the adjoining pipe or fitting. This flange type is used in applications where frequent dismantling is required, such as in pipelines that need to be cleaned regularly.

5. Blind flanges, also known as blanking flanges, are used to seal off the end of a pipe. This flange is commonly used in the oil and gas industry to seal off a pipeline that is no longer used.

6. Slip-on flanges are similar to flat flanges but have a slightly larger diameter and are designed to slide over the end of a pipe. They are then welded in place to create a strong and secure connection. Slip-on flanges are used in low-pressure applications and are commonly used in small-scale piping systems.

UNI flanges come in different types, each with unique characteristics and applications. Weld neck flanges are used in high-pressure applications, while threaded and flat flanges are used in low-pressure applications. Lap joint flanges are used in applications where frequent dismantling is required, and blind flanges are used to seal off the end of a pipe. Finally, slip-on flanges are used in low-pressure applications and are commonly used in small-scale piping systems. Understanding the different types of UNI flanges and their applications can help you choose the correct flange for your specific needs.

Advantages and disadvantages of UNI flanges

UNI flanges are a common type of flange used in various industrial applications. They are designed to connect pipes and other equipment and are known for their ability to withstand high pressures and temperatures. However, as with any additional equipment, UNI flanges have advantages and disadvantages. We discuss the pros and cons of UNI flanges so you can make an informed decision when selecting the correct flange for your application.

Advantages of UNI flanges

• High-pressure resistance: UNI flanges are known to withstand high pressures. They are designed to provide a secure and tight seal between two pipes, which is critical for applications that require high pressure.

• Temperature resistance: UNI flanges are also designed to withstand high temperatures. They are typically made of materials that can withstand high temperatures, making them ideal for high-temperature applications.

• Versatility: UNI flanges are available in various sizes and configurations, making them suitable for multiple applications. They can be used to connect pipes of different sizes and in a variety of materials.

• Easy to install: UNI flanges are relatively easy to install, saving you time and installation costs. They usually come with pre-drilled holes so they can easily be fixed to the equipment.

Disadvantages of UNI flanges

• Cost: UNI flanges can be more expensive than other types of flanges. This is because they are designed to withstand high pressures and temperatures, which require them to be made of high-quality materials.

• Maintenance: UNI flanges require regular maintenance to ensure they continue to work correctly. They must be checked regularly for signs of wear, and any damaged parts need to be replaced immediately.

• Weight: UNI flanges can be heavy, making them difficult to handle during installation. This is especially true for larger flanges, which weigh several hundred pounds.

• Limited availability: UNI flanges may only be available in some sizes and configurations, making it challenging to find the correct flange for your application.

UNI flanges are a popular choice for many industrial applications because of their high pressure and temperature resistance, versatility, and ease of installation. However, they have some drawbacks, including cost, maintenance requirements, weight and limited availability. When selecting a flange for your application, it is essential to weigh the advantages and disadvantages of UNI flanges against other types of flanges to determine which flange is best for your needs.

Flange Face Finish

Flange face finish is a crucial factor in ensuring proper sealing between flange connections. There are several types of flange face finishes available, each with its unique characteristics and benefits.
Types of Flange Face Finish
One type of flange face finish is the serrated finish. This finish is created by machining a series of grooves into the flange face, providing better grip and improved sealing when compressed. Serrated finishes are commonly used in applications where the flange connection may be subject to vibration or movement.
Another type of flange face finish is the stock finish. This is the default finish provided by the manufacturer, and it typically has a smooth surface. While it may not offer the same grip as a serrated finish, a stock finish is suitable for many standard applications.

Spiral serrated finishes feature a spiral pattern of grooves that helps to distribute stress evenly across the flange face. This can help to prevent damage and distortion, which can lead to leaks or other issues.

Concentric serrated finishes are similar to spiral serrated finishes but feature a series of concentric rings around the flange face. This pattern can provide enhanced sealing and grip compared to other types of serrated finishes.

Finally, a smooth finish is another option for flange face finish. Smooth finishes are often used in applications where the flange connection is not subject to significant movement or vibration. While it may not offer the same grip as a serrated finish, a smooth finish can still provide a reliable seal in many standard applications.

For example:

Machining of gasket faces of flanges to a smooth finish of Ra = 3.2 – 6.3 micrometer (= 125 – 250 microinches AARH)

• AARH stands for Arithmetic Average Roughness Height. It is used to measure the roughness (rather smoothness) of surfaces. 125 AARH means 125 micro inches will be the average height of the ups and downs of the surface.
• 63 AARH is specified for Ring Type Joints.
• 125-250 AARH (it is called smooth finish) is specified for Spiral Wound Gaskets.
• 250-500 AARH (it is called stock finish) is specified for soft gaskets such as NON Asbestos, Graphite sheets, Elastomers etc. If we use smooth finish for soft gaskets enough “biting effect” will not occur and hence the joint may develop leak.
• Sometimes AARH is referred also as Ra which stands for Roughness Average and means the same.

Selecting the appropriate flange face finish is essential to ensuring a proper seal between flange connections. Whether you choose a serrated finish, stock finish, spiral serrated, concentric serrated, or smooth finish, it is important to consider the specific application and potential stresses that the flange connection may face. By selecting the right finish for the job, you can help to prevent leaks and other issues that can lead to costly downtime and repairs.

Standard Specication For UNI Flanges

• Dimensions : ANSI B16.5, ANSI B16.47 Series A & B, UNI, ASA, API-605, AWWA, Custom Drawings
• Size : 1/2″ (15 NB) to 48″ (1200NB)
• Class : 150 LBS, 300 LBS, 600 LBS, 900 LBS, 1500 LBS, 2500 LBS, DIN Standard ND-6,10, 16, 25, 40 Etc.
• DIN : DIN2527, DIN2566, DIN2573, DIN2576, DIN2641, DIN2642, DIN2655, DIN2656, DIN2627, DIN2628, DIN2629,
• DIN 2631, DIN2632, DIN2633, DIN2634, DIN2635, DIN2636,DIN2637, DIN2638, DIN2673
• BS : BS4504 , BS4504, BS1560, BS10
• Flange Face Type : Flate Face (FF), Raised Face(RF), Ring Type Joint (RTJ)

Material of UNI Flanges

The selection of materials for UNI Flanges typically varies according to the specific application and desired properties. Carbon steel, stainless steel, cast iron, brass, and aluminum are common materials used for manufacturing UNI Flanges. The selection process usually considers factors like temperature, pressure, the corrosiveness of the fluid or gas being conveyed, and any applicable regulatory requirements or industry standards. Therefore, some of the materials commonly utilized for UNI flanges comprise:

Stainless Steel UNI Flange	ASTM/ASME A/SA182:- F304, F304L, F316, F316L, ASTM/ASME A/SA351:- CF3, CF3M, CF8, CF8M, DIN 1.4306, DIN 1.4301, DIN 1.4404, DIN 1.4401, DIN 1.4408, DIN 1.4308, DIN 1.4306, DIN 1.4409
Duplex UNI Flange	S31803 / S32205 A182:- Gr F51 / F52 / F53 / F54 / F55 / F57 / F59 / F60 / F61
Super Duplex UNI Flange	S32750 / S32760 A182:- Gr F51 / F52 / F53 / F54 / F55 / F57 / F59 / F60 / F61
Copper Nickel UNI Flange	ASTM / ASME SB 61 / 62 / 151 / 152, Copper Nickel 90/10 (C70600 ), Cupro Nickel 70/30 (C71500), UNS C71640
Titanium UNI Flange	ASTM B381 / ASME SB381:- Titanium Gr. 1, Titanium Gr. 2, Titanium Gr. 4, Titanium Gr. 5, Titanium Gr. 7, ASTM R50250/GR.1|R50400/GR.2|R50550/GR.3|R50700/GR.4|GR.6|R52400/GR.7| R53400/GR.12|R56320/GR.9| R56400/GR.5
Copper UNI Flange	TP1, TP2, C10930, C11000, C11300, C11400, C11500, C11600, C12000, C12200, C12300, T1, T2, C10100, C10200, C10300, C10400, C10500, C10700, C10800, C10910, C10920, TU1, TU2, C12500, C14200, C14420, C14500, C14510, C14520, C14530, C17200, C19200, C21000, C23000, C26000, C27000, C27400, C28000, C33000, C33200, C37000, C44300, C44400, C44500, C60800, C63020, C68700, C70400, C70600, C70620, C71000, C71500, C71520, C71640, etc
Incoloy UNI Flange	ASTM B564 / ASME SB564:- Incoloy 800, 800H, 800HT (UNS N08800), 825 (UNS N08825), 925
Inconel UNI Flange	ASTM B564 / ASME SB564:- Inconel 600, 601, 625, 718, 783, 690, x750
Nickel UNI Flange	ASTM B564 / ASME SB564:- Nickel 200, Nickel 201, Nickel 205, Nickel 205LC
Hastelloy UNI Flange	ASTM B564 / ASME SB564:- Hastelloy C276 (UNS N10276), C22 (UNS N06022), C4, C2000, B2, B3, X
Monel UNI Flange	ASTM B564 / ASME SB564:- Monel 400 (UNS No. N04400), Monel 500 (UNS No. N05500)
Carbon Steel UNI Flange	ASTM/ASME A/SA105 A/SA105N and A/SA216-WCB, DIN 1.0460, DIN 1.0402, DIN 1.0619, Die Steel, ASTM A105 / ASME SA105, A105N, ASTM A350 LF2 / ASME SA350, CS High Yield ASTM A694 / A694 (F52, F56, F60, F65, F70, F80)
Alloy Steel UNI Flange	ASTM A182 / ASME SA182:- F5, F9, F11, F12, F22, F91
Alloy 20 UNI Flange	ASTM B462 / ASME SB462:- Carpenter 20 Alloy, Alloy 20Cb-3
254 SMO UNI Flange	ASTM A182 / ASME SA182:- SMO 254/6Mo, UNS S31254, DIN 1.4547
Aluminium UNI Flange	5052 /6061/ 6063 / 2017 / 7075 / etc.
Brass UNI Flange	3602 / 2604 / H59 / H62 / etc.
Other UNI Flange material	Tin bronze, Alumunum bronze, Lead bronze, Nimonic 75, Nimonic 80A, Nimonic 90, AISI 4140, AISI 4130, Mild Steel, Al6XN

Size of UNI Flanges

The size of UNI flanges depends on the expected pipe diameter, with standard sizes typically ranging from DN15 (15 mm or 1/2 inch) to DN600 (600 mm or 24 inches). While larger UNI flanges can be manufactured, such custom fabrication is not standard. It is important to select the proper UNI flange size to ensure a secure connection and avoid leaks.

Dimensions of UNI Flanges

The most commonly used flange types in UNI standards include UNI 2276 PN6, UNI 2277 PN10, UNI 2278 PN16, UNI6083 PN25, UNI 6084 PN40, and UNI 6089 PN6-PN100. Each flange type has standard dimensions; some of the common ones include the following:

• Outside diameter (OD): The overall dimension of the flange, which is the outside diameter of the flange.

• Bolt Circle Diameter (BCD): The circle’s diameter that holds the bolt in place.

• Several bolt holes: The number of bolt holes in the flange.

• Bolt hole diameter: The diameter of the bolt hole.

• Thickness: The thickness of the flange.

The exact dimensions of each UNI flange type can be found in the UNI standard, but these dimensions may vary depending on the flange’s specific size and pressure class.

The exact dimensions of each UNI flange type can be found in the UNI standard, but these dimensions may vary depending on the flange’s specific size and pressure class.

Dimensions of UNI plate flange

UNI 2276 plate flange PN6

ITALIAN STANDARDS UNI 2276 PLATE FLANGE PN 6
Directions for the designation		d1		a	b	D	f	Holes	Screws	Weight*
Rated Diameter	External diameter of the pipe	Nominal	Tolerance							Kg
15	20	20,5	+0,5	55	10	80	11	4	M 10	0,34
	21,3	22								0,33
20	25	25,5		65	12	90	11	4	M 10	0,51
	26,9	27,5								0,50
25	30	30,5		75	12	100	11	4	M 10	0,63
	33,7	34								0,61
32	38	38,5		90	14	120	14	4	M 12	1,09
	42,4	43								1,05
40	44,5	45		100	14	130	14	4	M 12	1,26
	48,3	49								1,23
50	57	58		110	14	140	14	4	M 12	1,38
	60,3	61,5								1,35
65	76,1	77		130	14	160	14	4	M 12	1,68
80	88,9	90		150	16	190	18	4	M 16	2,63
100	108	109	+1,0	170	16	210	18	4***	M 16	3,05
	114,3	115,5								2,92
125	133	134,5		200	18	240	18	8	M 16	4,11
	139,7	141								3,90
150	159	160,5		225	20	265	18	8	M 16	5,16
	168,3	170								4,78
175	193,7	195,5		255	22	295	18	8	M 16	6,27
200	219,1	221		280	22	320	18	8	M 16	6,91
250	267	269		335	24	375	18	12	M 16	9,53
	273	275								9,04
300	323,9	326		395	24	440	22	12	M 20	12,1
350	355,6	358		445	26	490	22	12	M 20	17,0
	368	370,5								15,6
400	406,4	409	+1,5	495	28	540	22	16	M 20	20,1
	419	422								18,3
450	457,2	460,2	±5	550	28	595	22	16	M 20	25,8
500	508	511		600	30	645	22	20	M 20	30,0
600	609,6	612,6		705	30	755	25	20	M 22	37,9
700	711,2	714,2		810	32	860	25	24	M 22	47,9
800	812,8	815,8		920	34	975	30	24	M 27	62,9
900	914,4	917,4		1020	36	1075	30	24	M 27	74,6
1000	1016	1019		1120	36	1175	30	28	M 27	81,9
*	The weight is approximate and calculated on base 7.85 Kg/dm3
**	Raw hole to be worked again according to the real external diameter of the pipe
***	For oil piping the flange should have 8 holes

UNI 2277 plate flange PN10

ITALIAN STANDARDS UNI 2277 PLATE FLANGE PN 10
Directions for the designation		d1		a	b	D	f	Holes	screws	Weight*
Rated Diameter	External diameter of the pipe	Nominal	Tolerance							Kg
15	20	20,5	+0,5	65	12	95	14	4	M 12	0,67
	21,3	22								0,66
20	25	25,5		75	14	105	14	4	M 12	0,83
	26,9	27,5								0,82
25	30	30,5		85	14	115	14	4	M 12	1,03
	33,7	34								1,01
32	38	38,5		100	16	140	18	4	M 16	1,66
	42,4	43								1,63
40	44,5	45		110	16	150	18	4	M 16	1,89
	48,3	49								1,85
50	57	58		125	18	165	18	4	M 16	2,51
	60,3	61,5								2,46
65	76,1	77		145	18	185	18	4	M 16	3,00
80	88,9	90		160	20	200	18	4	M 16	3,61
100	108	109	+1,0	180	22	220	18	8	M 16	4,60
	114,3	115,5								4,40
125	133	134,5		210	24	250	18	8	M 16	6,19
	139,7	141								5,92
150	159	160,5		240	24	285	22	8	M 20	7,63
	168,3	170								7,17
175	193,7	195,5		270	26	315	22	8	M 20	9,16
200	219,1	221		295	26	340	22	8	M 20	10,1
250	267	269		350	28	395	22	12	M 20	13,4
	273	275								12,9
300	323,9	326		400	28	445	22	12	M 22	14,8
350	355,6	358		460	30	505	22	16	M 20	22,0
	368	370,5								20,4
400	406,4	409	+1,5	515	32	565	25	16	M 22	28,0
	419	422								25,9
450	457,2	460,2	±5	565	32	615	25	20	M 22	33,3
500	508	511		620	34	670	25	20	M 22	40,3
600	609,6	612,6		725	36	780	30	20	M 27	53,0
*	The weight is approximate and calculated on base 7.85 Kg/dm3

UNI 2278 plate flange PN16

ITALIAN STANDARDS UNI 2278 PLATE FLANGE PN 16
Directions for the designation		d1		a	b	D	f	Holes	screws	Weight* Kg
Rated Diameter	External diameter of the pipe	Nominal	Tolerance
15	20	20,5	+0,5	65	12	95	14	4	M 12	0,67
	21,3	22								0,66
20	25	25,5		75	14	105	14	4	M 12	0,83
	26,9	27,5								0,82
25	30	30,5		85	14	115	14	4	M 12	1,03
	33,7	34								1,01
32	38	38,5		100	16	140	18	4	M 16	1,66
	42,4	43								1,63
40	44,5	45		110	16	150	18	4	M 16	1,89
	48,3	49								1,85
50	57	58		125	18	165	18	4	M 16	2,51
	60,3	61,5								2,46
65	76,1	77		145	18	185	18	4	M 16	3,00
80	88,9	90		160	20	200	18	8**	M 16	3,61
100	108	109	+1,0	180	22	220	18	8	M 16	4,60
	114,3	115,5								4,40
125	133	134,5		210	24	250	18	8	M 16	6,19
	139,7	141								5,92
150	159	160,5		240	24	285	22	8	M 20	7,63
	168,3	170								7,17
175	193,7	195,5		270	26	315	22	8	M 20	9,16
200	219,1	221		295	26	340	22	12	M 20	9,77
250	267	269		355	32	405	25	12	M 22	16,6
	273	275								16,0
300	323,9	326		410	32	460	25	12	M 22	19,3
350	355,6	358		470	36	520	25	16	M 22	29,4
	368	370,5								27,3
400	406,4	409	+1,5	525	38	580	30	16	M 27	36,5
	419	422								33,9
*	The weight is approximate and calculated on base 7.85 Kg/dm3
**	For PN10 the flange should have 4 holes

Dimensions of UNI weld neck flanges

UNI 2280 weld neck flange PN6

ITALIAN STANDARDS UNI 2280 WELD NECK FLANGE RF PN 6
Directions for the designation		d1	a	b	D	f	h	h1	m	r	s	Holes	Screws	Weight* Kg
Rated Diameter	External diameter of the pipe
15	20	21	55	12	80	11	30	6	28	4	2,5	4	M 10	0,45
	21,3	22,5							30					0,45
20	25	26	65	14	90	11	32	6	35	4	2,5	4	M 10	0,66
	26,9	28							38					0,66
25	30	31	75	14	100	11	35	6	40	4	2,8	4	M 10	0,83
	33,7	34,5							42					0,82
32	38	39	90	14	120	14	35	6	50	6	3	4	M 12	1,18
	42,4	43,5							55					1,16
40	44,5	45,5	100	14	130	14	38	7	58	6	3	4	M 12	1,40
	48,3	49,5							62					1,38
50	57	58	110	14	140	14	38	8	70	6	3,5	4	M 12	1,58
	60,3	61,5							74					1,56
65	76,1	77	130	14	160	14	38	9	88	6	3,5	4	M 12	1,95
80	88,9	90	150	16	190	18	42	10	102	8	3,7	4	M 16	3,07
100	108	109	170	16	210	18	45	10	122	8	3,7	4**	M 16	3,68
	114,3	115,5							130					3,56
125	133	134	200	18	240	18	48	10	148	8	4	8	M 16	5,04
	139,7	141							155					4,80
150	159	161	225	18	265	18	48	12	172	10	5	8	M 16	5,75
	168,3	170,5							184					5,52
175	193,7	195,5	255	20	295	18	52	12	208	10	5	8	M 16	7,22
200	219,1	221	280	20	320	18	55	15	236	10	5	8	M 16	8,16
250	267	269	335	22	375	18	60	15	282	12	5,5	12	M 16	11,4
	273	275							290					11,1
300	323,9	326	395	22	440	22	62	15	342	12	6	12	M 20	14,8
350	355,6	357,5	445	22	490	22	62	15	385	12	6,5	12	M 20	19,5
	368	370												17,7
400	406,4	408,5	495	22	540	22	65	15	438	12	7	16	M 20	22,5
	419	421												20,3
450	457,2	459	550	22	595	22	65	15	476	12	7,3	16	M 20	25,0
500	508	510	600	24	645	22	68	15	538	12	7,3	20	M 20	30,4
600	609,6	611,5	705	24	755	25	70	16	640	12	7,3	20	M 22	38,0
700	711,2	715	810	24	860	25	70	16	740	12	9	24	M 22	45,9
800	812,8	817	920	24	975	30	70	16	842	12	9	24	M 27	55,0
900	914,4	918	1020	26	1075	30	70	16	942	12	9	24	M 27	64,7
1000	1016	1020	1120	26	1175	30	70	16	1045	16	9	28	M 27	70,6
1200	1220	1224	1340	28	1405	33	90	20	1248	16	9	32	M 30	108
1400	1420	1424	1560	32	1630	36	90	20	1452	16	9	36	M 33	153
1600	1620	1624	1760	34	1830	36	90	20	1655	16	11	40	M 33	189
1800	1820	1824	1970	36	2045	39	100	20	1855	16	11	44	M 36 x 3	239
2000	2020	2024	2180	38	2265	42	110	25	2058	16	12	48	M 39 x 3	308
*	The weight is approximate and calculated on base 7.85 Kg/dm3
**	For oil piping the flange should have 8 holes

UNI 2281 weld neck flange PN10

ITALIAN STANDARDS UNI 2281 WELD NECK FLANGE RF PN 10
Directions for the designation		d1	a	b	D	f	h	h1	m	r	s	Holes	Screws	Weight*
Rated Diameter	External diameter of the pipe													Kg
15	20	21	65	14	95	14	35	6	30	4	2,5	4	M 12	0,73
	21,3	22,5							32					0,73
20	25	26	75	16	105	14	38	6	38	4	2,5	4	M 12	1,03
	26,9	28							40					1,03
25	30	31	85	16	115	14	38	6	42	4	2,8	4	M 12	1,24
	33,7	34,5							45					1,23
32	38	39	100	16	140	18	40	6	52	6	3	4	M 16	1,82
	42,4	43,5							56					1,80
40	44,5	45,5	110	16	150	18	42	7	60	6	3	4	M 16	2,10
	48,3	49,5							64					2,08
50	57	58	125	18	165	18	45	8	72	6	3,5	4	M 16	2,81
	60,3	61,5							75					2,78
65	76,1	77	145	18	185	18	45	10	90	6	3,5	4	M 16	3,40
80	88,9	90	160	20	200	18	50	10	105	8	3,7	8**	M 16	4,20
100	108	109	180	20	220	18	52	12	125	8	3,7	8	M 16	4,90
	114,3	115,5							131					4,75
125	133	134	210	22	250	18	55	12	150	8	4	8	M 16	6,70
	139,7	141							156					6,45
150	159	161	240	22	285	22	55	12	175	10	5	8	M 20	8,30
	168,3	170,5							184					8,00
175	193,7	195,5	270	24	315	22	60	12	210	10	5	8	M 20	10,3
200	219,1	221	295	24	340	22	62	16	235	10	5	8	M 20	11,4
250	267	269	350	26	395	22	68	16	285	12	5,5	12	M 20	15,6
	273	275							292					15,2
300	323,9	326	400	26	445	22	68	16	344	12	6	12	M 20	18,0
350	355,6	357,5	460	26	505	22	68	16	385	12	6,4	16	M 20	24,5
	368	370												22,5
400	406,4	408,5	515	26	565	25	72	16	440	12	7	16	M 22	30,2
	419	421												27,8
450	457,2	459	565	26	615	25	72	16	478	12	7,3	20	M 22	32,3
500	508	510	620	28	670	25	75	16	542	12	7,3	20	M 22	40,4
600	609,6	611,5	725	28	780	30	80	18	642	12	7,3	20	M 27	50,0
700	711,2	715	840	30	895	30	80	18	745	12	9	24	M 27	66,4
800	812,8	817	950	32	1015	33	90	18	850	12	9	24	M 30	89,3
900	914,4	918	1050	34	1115	33	95	20	950	12	9	28	M 30	104
1000	1016	1020	1160	34	1230	36	95	20	1052	16	9	28	M 33	121
1200	1220	1224	1380	38	1455	39	115	25	1255	16	10	32	M 36 x 3	180
1400	1420	1424	1590	42	1675	42	120	25	1460	16	11	36	M 39 x 3	248
1600	1620	1624	1820	46	1915	48	130	25	1665	16	12	40	M 45 x 3	352
1800	1820	1824	2020	50	2115	48	140	30	1868	16	13	44	M 45 x 3	433
2000	2020	2024	2230	54	2325	48	150	30	2072	16	14	48	M 45 x 3	543
*	The weight is approximate and calculated on base 7.85 Kg/dm3
**	For PN10 the flange should have 4 holes

UNI 2282 weld neck flange PN16

ITALIAN STANDARDS UNI 2282 WELD NECK FLANGE RF PN 16
Directions for the designation		d1	a	b	D	f	h	h1	m	r	s	Holes	Screws	Weight*
Rated Diameter	External diameter of the pipe													Kg
15	20	21	65	14	95	14	35	6	30	4	2,5	4	M 12	0,73
	21,3	22,5							32					0,73
20	25	26	75	16	105	14	38	6	38	4	2,5	4	M 12	1,03
	26,9	28							40					1,03
25	30	31	85	16	115	14	38	6	42	4	2,8	4	M 12	1,24
	33,7	34,5							45					1,23
32	38	39	100	16	140	18	40	6	52	6	3	4	M 16	1,82
	42,4	43,5							56					1,80
40	44,5	45,5	110	16	150	18	42	7	60	6	3	4	M 16	2,10
	48,3	49,5							64					2,08
50	57	58	125	18	165	18	45	8	72	6	3,5	4	M 16	2,81
	60,3	61,5							75					2,78
65	76,1	77	145	18	185	18	45	10	90	6	3,5	4	M 16	3,40
80	88,9	90	160	20	200	18	50	10	105	8	3,7	8**	M 16	4,20
100	108	109	180	20	220	18	52	12	125	8	3,7	8	M 16	4,90
	114,3	115,5							131					4,75
125	133	134	210	22	250	18	55	12	150	8	4	8	M 16	6,70
	139,7	141							156					6,45
150	159	161	240	22	285	22	55	12	175	10	5	8	M 20	8,30
	168,3	170,5							184					8,00
175	193,7	195,5	270	24	315	22	60	12	210	10	5	8	M 20	10,3
200	219,1	221	295	24	340	22	62	16	235	10	5	12	M 20	11,1
250	267	269	355	26	405	25	70	16	285	12	5,5	12	M 22	16,7
	273	275							292					16,3
300	323,9	326	410	28	460	25	78	16	344	12	6	12	M 22	21,8
350	355,6	357,5	470	30	520	25	82	16	390	12	6,4	16	M 22	31,7
	368	370												29,2
400	406,4	408,5	525	32	580	30	85	16	445	12	7	16	M 27	38,3
	419	421												37,0
450	457,2	459	585	32	640	30	85	16	485	12	7,3	20	M 27	45,4
500	508	510	650	34	715	33	90	16	548	12	7,3	20	M 30	61,1
600	609,6	611,5	770	36	840	36	95	18	652	12	7,3	20	M 33	84,6
700	711,2	715	840	36	910	39	100	18	755	12	9	24	M 33	87,4
800	812,8	817	950	38	1025	39	105	20	855	12	9	24	M 36 x 3	109
900	914,4	918	1050	40	1125	42	110	20	955	12	10	28	M 36 x 3	129
1000	1016	1020	1170	42	1255	48	120	22	1058	16	12	28	M 39 x 3	175
1200	1220	1224	1390	48	1485	48	130	30	1262	16	14	32	M 45 x 3	257
1400	1420	1424	1590	52	1685	48	145	30	1465	16	16	36	M 45 x 3	337
1600	1620	1624	1820	58	1930	56	160	35	1668	16	17	40	M 52 x 3	481
1800	1820	1824	2020	62	2130	56	170	35	1870	16	19	44	M 52 x 3	591
2000	2020	2024	2230	66	2345	62	180	40	2072	16	21	48	M 56 x 4	727
*	The weight is approximate and calculated on base 7.85 Kg/dm3
**	For PN10 the flange should have 4 holes

UNI 2283 weld neck flange PN25

ITALIAN STANDARDS UNI 2283 WELD NECK FLANGE RF PN 25
Directions for the designation		d1	a	b	D	f	h	h1	m	r	s	Holes	Screws	Weight*
Rated Diameter	External diameter of the pipe													Kg
15	20	21	65	16	95	14	38	6	30	4	2,5	4	M 12	0,83
	21,3	22,5							32					0,83
20	25	26	75	18	105	14	40	6	38	4	2,5	4	M 12	1,15
	26,9	28							40					1,15
25	30	31	85	18	115	14	40	6	42	4	2,8	4	M 12	1,39
	33,7	34,5							46					1,38
32	38	39	100	18	140	18	42	6	52	6	3	4	M 16	2,03
	42,4	43,5							56					2,01
40	44,5	45,5	110	18	150	18	45	7	60	6	3	4	M 16	2,35
	48,3	49,5							64					2,33
50	57	58	125	20	165	18	48	8	72	6	3,5	4	M 16	3,11
	60,3	61,5							75					3.08
65	76,1	77	145	22	185	18	52	10	90	6	3,5	8	M 16	3,95
80	88,9	90	160	24	200	18	58	12	105	8	3,7	8	M 16	4,98
100	108	109	190	24	235	22	65	12	128	8	3,7	8	M 20	6,85
	114,3	115,5							134					6,70
125	133	134	220	26	270	25	68	12	155	8	4	8	M 22	9,42
	139,7	141							162					9,20
150	159	161	250	28	300	25	75	12	182	10	5	8	M 22	12,4
	168,3	170,5							192					12,0
175	193,7	195,5	280	28	330	25	75	15	218	10	5	12	M 22	13,6
200	219,1	221	310	30	360	25	80	16	244	10	5	12	M 22	16,8
250	267	269	370	32	425	30	88	18	292	12	5,5	12	M 27	23,8
	273	275							298					23,3
300	323,9	326	430	34	485	30	92	18	352	12	6	16	M 27	30,5
350	355,6	357,5	490	38	555	33	100	20	398	12	6,4	16	M 30	47,6
	368	370												44,5
400	406,4	408,5	550	40	620	36	110	20	452	12	7,3	16	M 33	62,1
	419	421												58,3
450	457,2	459	600	40	670	36	115	20	492	12	8	20	M 33	67,8
500	508	510	660	44	730	36	125	20	558	12	8	20	M 33	88,8
600	609,6	611,5	770	46	845	39	125	20	660	12	8	20	M 36 x 3	114
700	711,2	715	875	46	960	42	125	20	760	12	10	24	M 39 x 3	138
800	812,8	817	990	50	1085	48	135	22	865	12	11	24	M 45 x 3	185
900	914,4	918	1090	54	1185	48	145	24	968	12	12	28	M 45 x 3	224
1000	1016	1020	1210	58	1320	56	155	24	1070	16	13	28	M 52 x 3	293
*	The weight is approximate and calculated on base 7.85 Kg/dm3

UNI 2284 weld neck flange PN40

ITALIAN STANDARDS UNI 2284 WELD NECK FLANGE RF PN 40
Directions for the designation		d1	a	b	D	f	h	h1	m	r	s	Holes	Screws	Weight*
Rated Diameter	External diameter of the pipe													Kg
15	20	21	65	16	95	14	38	6	30	4	2,5	4	M 12	0,83
	21,3	22,5							32					0,83
20	25	26	75	18	105	14	40	6	38	4	2,5	4	M 12	1,15
	26,9	28							40					1,15
25	30	31	85	18	115	14	40	6	42	4	2,8	4	M 12	1,39
	33,7	34,5							46					1,38
32	38	39	100	18	140	18	42	6	52	6	3	4	M 16	2,03
	42,4	43,5							56					2,01
40	44,5	45,5	110	18	150	18	45	7	60	6	3	4	M 16	2,35
	48,3	49,5							64					2,33
50	57	58	125	20	165	18	48	8	72	6	3,5	4	M 16	3,11
	60,3	61,5							75					3.08
65	76,1	77	145	22	185	18	52	10	90	6	3,5	8	M 16	3,95
80	88,9	90	160	24	200	18	58	12	105	8	3,7	8	M 16	4,98
100	108	109	190	24	235	22	65	12	128	8	3,7	8	M 20	6,85
	114,3	115,5							134					6,70
125	133	134	220	26	270	25	68	12	155	8	4	8	M 22	9,42
	139,7	141							162					9,20
150	159	161	250	28	300	25	75	12	182	10	5	8	M 22	12,4
	168,3	170,5							192					12,0
175	193,7	195,5	295	32	350	30	82	15	218	10	5,5	12	M 27	17,6
200	219,1	221	320	34	375	30	88	16	244	12	5,5	12	M 27	20,8
250	267	269	385	38	450	33	105	18	298	12	6,5	12	M 30	34,3
	273	275							306					33,8
300	323,9	326	450	42	515	33	115	18	362	12	7,3	16	M 30	47,4
350	355,6	357,5	510	46	580	36	125	20	408	12	8	16	M 33	69,0
	368	370												65,0
400	406,4	408,5	585	50	660	39	135	20	462	12	9	16	M 36 x 3	96,5
	419	421												91,6
450	457,2	459	610	50	685	39	135	20	500	12	9	20	M 36 x 3	91,6
500	508	510	670	52	755	42	140	20	562	12	10	20	M 39 x 3	117
*	The weight is approximate and calculated on base 7.85 Kg/dm3

Dimensions of UNI blind flanges

UNI 6092 blind flange PN10

ITALIAN STANDARDS UNI 6092 BLIND FLANGE PN 10
Rated Diameter	a	b	D	f	Number of holes	Threading of the screws	Weight* in Kg
15	65	14	95	14	4	M 12	0,71
20	75	16	105	14	4	M 12	1,01
25	85	16	115	14	4	M 12	1,22
32	100	16	140	18	4	M 16	1,80
40	110	16	150	18	4	M 16	2,09
50	125	18	165	18	4	M 16	2,87
65	145	18	185	18	4	M 16	3,65
80	160	20	200	18	4	M 16	4,61
100	180	20	220	18	8	M 16	5,65
125	210	22	250	18	8	M 16	8,12
150	240	22	285	22	8	M 20	10,5
175	270	24	315	22	8	M 20	14,1
200	295	24	340	22	8	M 20	16,5
250	350	26	395	22	12	M 20	24,1
300	400	26	445	22	12	M 20	30,8
350	460	26	505	22	16	M 20	39,6
400	515	26	565	25	16	M 22	49,6
450	565	26	615	25	20	M 22	58,6
500	620	28	670	25	20	M 22	75,3
*	The weight is approximate and calculated on base 7.85 Kg/dm3

UNI 6093 blind flange PN16

ITALIAN STANDARDS UNI 6093 BLIND FLANGE PN 16
Rated Diameter	a	b	D	f	Number of holes	Threading of the screws	Weight* in Kg
15	65	14	95	14	4	M 12	0,71
20	75	16	105	14	4	M 12	1,01
25	85	16	115	14	4	M 12	1,22
32	100	16	140	18	4	M 16	1,80
40	110	16	150	18	4	M 16	2,09
50	125	18	165	18	4	M 16	2,87
65	145	18	185	18	4	M 16	3,65
80	160	20	200	18	8**	M 16	4,61
100	180	20	220	18	8	M 16	5,65
125	210	22	250	18	8	M 16	8,12
150	240	22	285	22	8	M 20	10,5
175	270	24	315	22	8	M 20	14,1
200	295	24	340	22	12	M 20	16,2
250	355	26	405	25	12	M 22	25,1
300	410	28	460	25	12	M 22	35,2
350	470	30	520	25	16	M 22	48,2
400	525	32	580	30	16	M 27	63,5
450	585	32	640	30	20	M 27	77,2
500	650	34	715	33	20	M 30	102
*	The weight is approximate and calculated on base 7.85 Kg/dm3
**	For PN10 the flange should have 4 holes

Dimensions of UNI threaded flanges

UNI 2253 threaded flange PN6

ITALIAN STANDARDS UNI 2253 THREADED FLANGE PN 6
Rated Diameter	d1	Flange					Neck	Raised face		Screws			Weight (7,85 Kg/dm3)
		Thread	D	b	k	h1	d3	d4	f	Number	Thread	d2	Kg
15	21,3	R 1/2	80	12	55	20	30	40	2	4	M 10	11	0,373
20	26,9	R 3/4	90	14	65	24	40	50	2	4	M 10	11	0,59
25	33,7	R 1	100	14	75	24	50	60	2	4	M 10	11	0,743
32	42,4	R 1 1/4	120	14	90	26	60	70	2	4	M 12	14	1,05
40	48,3	R 1 1/2	130	14	100	26	70	80	3	4	M 12	14	1,2
50	60,3	R 2	140	14	110	28	80	90	3	4	M 12	14	1,37
65	76,1	R 2 1/2	160	14	130	32	100	110	3	4	M 12	14	1,92
80	88,9	R 3	190	16	150	34	110	128	3	4	M 16	18	2,82
100	114,3	R 4	210	16	170	38	130	148	3	4	M 16	18	3,19
125	139,7	R 5	240	18	200	40	160	178	3	8	M 16	18	4,47
150	165,1	R 6	265	18	225	44	185	202	3	8	M 16	18	5,3

UNI 2254 threaded flange PN16

ITALIAN STANDARDS UNI 2254 THREADED FLANGE PN 16
Rated Diameter	d1	Flange					Neck	Raised face		Screws			Weight (7,85 Kg/dm3)
		Thread	D	b	k	h1	d3	d4	f	Number	Thread	d2	Kg
15	21,3	R 1/2	95	14	65	20	35	45	2	4	M 12	14	0,613
20	26,9	R 3/4	105	16	75	24	45	58	2	4	M 12	14	0,91
25	33,7	R 1	115	16	85	24	52	68	2	4	M 12	14	1,1
32	42,4	R 1 1/4	140	16	100	26	60	78	2	4	M 16	18	1,6
40	48,3	R 1 1/2	150	16	110	26	70	88	3	4	M 16	18	1,78
50	60,3	R 2	165	18	125	28	85	102	3	4	M 16	18	2,43
65	76,1	R 2 1/2	185	18	145	32	105	122	3	4	M 16	18	3,18
80	88,9	R 3	200	20	160	34	118	138	3	8	M 16	18	4,12
100	114,3	R 4	220	20	180	38	140	158	3	8	M 16	18	4,47
125	139,7	R 5	250	22	210	40	168	188	3	8	M 16	18	6,13
150	165,1	R 6	285	22	240	44	195	212	3	8	M 20	22	7,92

Dimensions of UNI lap joint flanges

UNI 6089 lap joint flange PN10

ITALIAN STANDARDS UNI 6089 LOOSE FLANGE PN 10
Directions for the designation		Lapped flanges							Sscrews	Weight of Flange
Rated Diameter	External diameter of the pipe	a	b	D	d2	f	t	Holes
25	30	85	16	115	33	14	4	4	M12	1,11
	33,7				37					1,08
32	38	100	16	140	41	18	4	4	M 16	1,63
	42,4				46					1,58
40	44,5	110	16	150	48	18	4	4	M 16	1,85
	48,3				52					1,81
50	57	125	16	165	62	18	4	4	M 16	2,16
	60,3				64					2,14
65	76,1	145	16	185	80	18	4	4	M 16	2,60
80	88,9	160	18	200	94	18	5	8**	M 16	3,14
100	108	180	18	220	113	18	5	8	M 16	3,63
	114,3				119					3,47
125	133	210	18	250	138	18	5	8	M 16	4,49
	139,7				145					4,26
150	159	240	18	285	164	22	5	8	M 20	5,54
	168,3				174					5,16
175	193,7	270	20	315	200	22	5	8	M 20	6,76
200	219,1	295	20	340	225	22	5	8	M 20	7,46
250	267	350	22	395	273	22	5	12	M 20	10,2
	273				279					9,73
300	323,9	400	26	445	330	22	5	12	M 20	13,2
350	355,6	460	28	505	362	22	5	16	M 20	19,9
	368				374					18,4
400	406,4	515	32	565	413	25	6	16	M 22	27,2
	419				426					25,0
450	457,2	565	34	615	464	25	6	20	M 22	31,3
500	508	620	38	670	515	25	6	20	M 22	39,9
600	609,6	725	44	780	618	30	6	20	M 27	56,3
700	711,2	840	50	895	721	30	6	24	M 27	79,7
800	812,8	950	56	1015	824	33	6	24	M 30	112
*	The weight is approximate and calculated on base 7.85 Kg/dm3
**	For PN10 the flange should have 4 holes

UNI 6090 lap joint flange PN16

ITALIAN STANDARDS UNI 6090 LOOSE FLANGE PN 16
Directions for the designation		Lapped flanges							Sscrews	Weight of Flange
Rated Diameter	External diameter of the pipe	a	b	D	d2	f	t	Holes
25	30	85	16	115	33	14	4	4	M12	1,11
	33,7				37					1,08
32	38	100	16	140	41	18	4	4	M 16	1,63
	42,4				46					1,58
40	44,5	110	16	150	48	18	4	4	M 16	1,85
	48,3				52					1,81
50	57	125	16	165	62	18	4	4	M 16	2,16
	60,3				64					2,14
65	76,1	145	16	185	80	18	4	4	M 16	2,60
80	88,9	160	18	200	94	18	5	8***	M 16	3,14
100	108	180	18	220	113	18	5	8	M 16	3,63
	114,3				119					3,47
125	133	210	18	250	138	18	5	8	M 16	4,49
	139,7				145					4,26
150	159	240	18	285	164	22	5	8	M 20	5,54
	168,3				174					5,16
175	193,7	270	20	315	200	22	5	8	M 20	6,76
200	219,1	295	20	340	225	22	5	12	M 20	7,22
250	267	355	24	405	273	25	5	12	M 22	12,0
	273				279					11,6
300	323,9	410	28	460	330	25	5	12	M 22	16,3
350	355,6	470	32	520	362	25	5	16	M 22	25,4
	368				374					23,6
400	406,4	525	36	580	413	30	6	16	M 27	33,4
	419				426					31,0
450	457,2	585	40	640	464	30	6	20	M 27	43,3
500	508	650	44	715	515	33	6	20	M 30	60,6
*	The weight is approximate and calculated on base 7.85 Kg/dm3
**	Raw hole to be worked again according to the real external diameter of the pipe
***	For PN10 the flange should have 4 holes

Manufacturing process of UNI flange

UNI flanges can be produced by forging, casting, cutting or rolling. We mainly produce flanges by forging, cutting and rolling processes.

Manufacturing process of UNI forged flange

The welding neck flanges shall be forged steel, and the blind flanges may be made from either forged steel or from steel plate.

• Raw material inspection – The key raw material used to produce flanges is billet or hot rolled bar stock. All raw materials purchased are supplied with test reports in accordance with British Standards with full traceability. This is the first mandatory step in the flange production process to ensure good quality. The raw materials are retested in-house to ensure chemical composition, mechanical properties and metallographic analysis.
• Cutting of raw materials – Correct and strict control of cutting sizes and proportions ensures full cost control.
• Heating – This is a very important step for the quality of the flanges. It is necessary to keep detailed records of heating temperatures to avoid overheating. Overheating can damage the structure of the metal and the mechanical properties of the raw material.
• Forging – The forging process is divided into free forging and die forging. The forging time and strength of flanges vary for different pressure classes.
• Heat treatment-The purpose of heat treatment is to eliminate the stress inside the flange and make the density more uniform. Careful recording of heat treatment temperature and cooling time is the key.
• Inspection of forging blanks – After the heat treatment process, select batch samples are tested again for chemical composition and mechanical properties to ensure that all items pass.
• Machining of forging blanks – During machining, inspection is performed along with machining to ensure that each part of the flange is qualified. Machining is performed on CNC and/or lathes.
• Finished Product Inspection – The finished product will be inspected 100% prior to delivery to ensure that the goods meet UNI, ASME, EN or customer standards.
• Documented Documentation – The entire production process and quality checks at different levels are documented according to UNI compliant standard operating procedures. This is the guarantee of good quality.
• Test certificates: As we are an UNI and PED certified manufacturer, we can issue test certificates for all goods upon delivery and inspection in accordance with British Standards.
• Packaging: All forgings and flanges are packed in wooden boxes or crates or pallets to ensure safe movement of the goods.

Manufacturing process of UNI plate cutting flange

The process here is relatively simple, and the key raw material is hot rolled plate. The process is mainly used to produce lower thickness sliding plate flanges and blind flanges. All plates purchased are accompanied by a test certificate to UNI Standards.
The circles are cut from the plates.
No heat treatment is involved in the flange manufacturing process.
Drilling and machining is carried out on the circles to obtain the required dimensions.
The goods are visually inspected and marked in accordance with the relevant standards.

Marking of UNI Flanges

UNI Flanges are typically marked with various information that helps identify the flange’s characteristics and properties. The markings can vary slightly depending on the specific standard and type of flange. Here are some typical markings found on UNI flanges:

• Manufacturer’s name or trademark.
• Flange standard designation (e.g., UNI 2278-67).
• Nominal pipe size (NPS) or nominal bore size (DN).
• Pressure rating (PN) or pressure class (e.g., PN 16 or Class 150).
• Material identification (e.g., carbon steel, stainless steel, etc.).
• Heat code or heat number (used for traceability).
• Identify the flange’s facing type (e.g., raised face, flat face, ring type joint, etc.).
• Bolt hole diameter and several bolt holes.
• Manufacturing date or code.

Any additional markings or symbols required by the specific standard or application.
Specific markings may only be present on particular flanges, and some industries or applications may require additional markings. It is crucial to verify that the markings on the flange meet the necessary specifications for the intended use to guarantee proper fit and optimal performance.

Packing of UNI Flanges

How to package UNI flanges?

Packaging UNI flanges typically involves the following steps:

• 1. Clean the Flanges: Before packaging, ensure that the UNI flanges are thoroughly cleaned and free from debris or contaminants.
• 2. Wrap the Flanges: Wrap each UNI flange individually with a layer of protective material, such as bubble wrap or foam, to prevent them from being scratched or damaged during transportation.
• 3. Choose a Sturdy Box: It’s crucial to select a sturdy box that is appropriate for the flanges. This will prevent them from moving around and potentially getting damaged.
• 4. Add Protective Fillers: Once the box has been chosen, add protective fillers such as packing peanuts or air pillows to the empty spaces between the flanges. This will prevent them from shifting during transport, providing an extra layer of protection.5. Seal the Box: Use strong packing tape to close and seal the box. Make sure that the video is applied evenly and covers all seams and corners of the box.
• 6. Label the Box: It’s essential to label your package with all the necessary shipping information. Make sure to include the destination address, return address, and any handling instructions to ensure your package arrives at its intended location without any issues.
• 7. Choose a Reliable Shipping Service: A reliable and trusted shipping service is crucial to ensure your package is handled and delivered safely and on time. Research different shipping services and choose the one that best fits your needs, considering factors such as speed, cost, and package size.

Following these steps, you can effectively package UNI flanges for safe and secure transportation.

Inspection and measurement of UNI Flanges

The examination and quantification of UNI flanges encompass evaluating their material composition, dimensions, surface texture, alignment of bolt holes, size of bolt holes, and thread used in bolt holes.
Material:
UNI flanges are typically made from carbon steel, stainless steel, or alloy steel. The choice of material depends on the specific application and the environmental conditions to which the flange will be exposed. The most common material for UNI flanges is carbon steel, which is known for its high strength and durability.
Dimension:
The dimension of a UNI flange is an essential factor to consider, as it affects the overall performance and compatibility with other components in the system. The dimensions of UNI flanges are standardized, with different classes and sizes available. The dimensions of a UNI flange are typically specified in millimeters and include the outer diameter, inner diameter, thickness, and height.
Surface Finish:
The surface finish of a UNI flange is an essential factor to consider, as it affects the seal between the flange and the gasket. A smooth surface finish is necessary to ensure a tight seal and prevent leaks. The surface finish of UNI flanges is typically specified in micrometers, with different classes and ranges available.
Bolt Hole Alignment:
The bolt-hole alignment of a UNI flange is an essential factor to consider, as it affects the ease of installation and the system’s overall stability. The bolt holes must be appropriately aligned to ensure that the bolts can be tightened uniformly and that the flange can be securely attached to other components in the system.
Bolt Hole Size:
The bolt-hole size of a UNI flange is an essential factor to consider, as it affects the compatibility with other components in the system. The bolt hole size must be large enough to accommodate the bolts that attach the flange to other system members.
Bolt Hole Thread:
The bolt-hole thread of a UNI flange is an essential factor to consider, as it affects the compatibility with the bolts that will be used to attach the flange to other components in the system. The bolt-hole thread must be compatible with the bolts and be of the correct size and pitch.
By paying attention to these factors, you can ensure that your UNI flanges are compatible with other components in the system and will perform reliably over the long term.

Application of UNI Flanges

UNI Flanges are known to deliver exceptional performance and are generally developed for meeting the demands. These UNI Flange is use in various industries like:

• Stainless Steel UNI Flange uses in Oil and Gas Pipeline;
• UNI Flange uses in Chemical Industry;
• Alloy Steel UNI Flange uses in Plumbing;
• UNI Flange uses in Heating;
• UNI Flange uses in Water Supply Systems;
• UNI Flange uses in Power Plant;
• UNI Flange uses in Paper & Pulp Industry;
• UNI Flange uses in General Purpose Applications;
• Steel UNI Flange uses in Fabrication Industry;
• UNI Flange uses in Food Processing Industry;
• UNI Flange uses in Structural Pipe.

How to purchase the correct UNI flanges?

Purchasing the right UNI flange can be daunting whether you are a seasoned professional or new to the industry. From determining the materials needed to considering the price, several factors exist. We will detail the steps required to purchase the correct UNI flange for your needs.

Determining the required materials

The first step in purchasing the correct UNI flange is determining the required material. Various materials, including carbon steel, stainless steel, and alloy steel, can make UNI flanges. Your choice of material will depend on the application and environment in which you will use the flange. For instance, if you need a flange for high-temperature or corrosive environments, the best choice is high-temperature stainless steel or alloy.

Identifying Flange Types

After identifying the desired material, you must determine the flange type. UNI provides various flanges, such as butt-weld flanges, sliding flanges, threaded flanges, and socket weld flanges. Each class has unique features and benefits, and the choice depends on specific needs. For instance, high-pressure applications typically use butt-weld flanges, while low-pressure applications generally use slip-on flanges.

Determine flange size and pressure rating.

After determining the flange type, you must select the size and pressure rating. Various sizes and pressure ratings of UNI flanges are available, and choosing the correct size and pressure rating is critical to ensure that the flange works appropriately. Be sure to refer to industry standards and regulations when determining the right size and pressure rating for your needs.

Look for quality and certification.

Quality and certification are critical when purchasing UNI flanges. Look for flanges manufactured to industry standards and undergo strict quality control measures. In addition, look for flanges that have been certified by recognized organizations such as ISO, API, and ASME. These certifications show that the flanges have been tested and meet industry standards for quality and performance.

Consider Price

Finally, consider the price when purchasing UNI flanges. One should think about price and prioritize quality and performance when purchasing. Be sure to compare multiple suppliers’ prices and consider additional costs, such as shipping and handling.

Purchasing the correct UNI flange requires careful consideration of several factors. By determining the materials needed, identifying the flange type, choosing the flange size and pressure rating, looking for quality and certifications, and considering the price, you can make an informed decision and select the correct UNI flange for your needs.

How to select UNI flanges manufacturer?

If you’re in need of UNI flanges, choosing a manufacturer that you can rely on is crucial. With a wide variety of options available, it can be challenging to identify the one that can provide you with high-quality products and exceptional customer service. We’ll discuss the essential factors you should consider when selecting a UNI flange manufacturer.
Quality of Products
When it comes to UNI flanges, quality is king. When selecting a manufacturer, it is crucial to prioritize their reputation for producing high-quality products. To ensure that the flanges you receive are durable, reliable, and meet industry standards, consider a manufacturer that utilizes premium materials like stainless steel or carbon steel, and has an established quality control process in place. These factors are indicative of a trustworthy manufacturer who prioritizes excellence and reliability in their products.
Industry Experience
When selecting UNI flanges, it is imperative to take into account the manufacturer’s level of industry experience. A well-established company with a long-standing history of producing high-quality UNI flanges will undoubtedly have a proven track record of success. Opting for a manufacturer with ample experience will guarantee that your flanges will be precisely crafted to meet your specifications. Additionally, an experienced manufacturer can offer invaluable insights and recommendations on which flanges are best suited for your unique application.
Production Capacity
When selecting a manufacturer, it’s crucial to take into account their production capacity. You must ascertain whether they can handle large or intricate orders and whether they can meet delivery deadlines. To guarantee a satisfactory outcome, it’s advisable to choose a manufacturer with a spacious production facility and a proficient workforce. This will ensure that your order is processed promptly and to your precise specifications.
Pricing
When choosing a manufacturer, it’s essential to consider more than just the price. While cost is undoubtedly an important factor, it shouldn’t be the only consideration. It’s crucial to select a manufacturer that provides competitive pricing while still maintaining the highest quality standards. It’s important to remember that the cheapest option may not always be the most cost-effective one in the long run, as it could end up costing you more due to lower-quality products. Therefore, it’s crucial to balance affordability and quality to make a wise decision when selecting a manufacturer.
Customer Service
When selecting a manufacturer, it’s essential to take their level of customer service into account. To ensure a positive experience, opt for a company that is highly responsive to your inquiries, maintains clear communication throughout the ordering process, and offers a satisfaction guarantee. An excellent manufacturer should be dedicated to your satisfaction and willing to collaborate with you to resolve any problems that may arise. By prioritizing customer service, you can have confidence in your decision and enjoy a stress-free experience.
It’s crucial to select a manufacturer that provides excellent customer service, as this will ensure that you have a smooth and hassle-free experience from start to finish. By taking all of these factors into consideration, you can feel confident that you’ve made the best possible choice for your UNI flange needs.

Why Choose Jihua to Be Your UNI Flange Supplier?

If you’re looking for a reliable and trustworthy supplier of UNI flanges, consider choosing Jihua. As a well-established and reputable manufacturer and supplier of high-quality UNI flanges, Jihua has been satisfying customers worldwide for many years. Here are some reasons why Jihua might be the best fit for your UNI flange needs:

• First and foremost, Jihua is committed to providing high-quality UNI flanges made from top-quality materials and manufactured to the highest standards. The company maintains strict quality control procedures to ensure that each product meets or exceeds customer expectations.
• Additionally, Jihua offers competitive pricing on its products, which means you can get high-quality UNI flanges at an affordable price. This cost-effectiveness is due to Jihua’s efficient manufacturing and distribution processes.
• Moreover, Jihua offers a wide range of UNI flanges, including ANSI, DIN, JIS, EN, and other international standards. This diverse product range allows you to find the right product to meet your specific needs.
• Furthermore, Jihua is committed to providing excellent customer service and support to all of its customers. The company has a team of experienced professionals who are available to answer any questions or concerns you may have.
• Lastly, Jihua understands the importance of timely delivery and works hard to ensure that all orders are shipped out quickly and efficiently. This ensures that you receive your order in a timely manner, which is especially important for time-sensitive projects.

Jihua is a reliable and trustworthy supplier of UNI flanges that can meet your needs and exceed your expectations. Choose Jihua for high-quality products, competitive pricing, a wide range of products, excellent customer service, and fast delivery.

Export Country For UNI Flanges

MIDDLE EAST	AFRICA	NORTH AMERICA	EUROPE	ASIA	SOUTH AMERICA
Saudi Arabia	Nigeria	Usa	Russia	India	Argentina
Iran	Algeria	Canada	Norway	Singapore	Bolivia
Iraq	Angola	Mexico	Germany	Malaysia	Brazil
Uae	South Africa	Panama	France	Indonesia	Chile
Qatar	Libya	Costa Rica	Italy	Thailand	Venezuela
Bahrain	Egypt	Puerto Rica	Uk	Vietnam	Colombia
Oman	Sudan	Trinidad And Tobago	Spain	South Korea	Ecuador
Kuwait	Equatorial Guinea	Jamaica	Ukraine	Japan	Guyana
Turkey	The Republic Of Congo	Bahamas	Netherland	Sri Lanka	Paraguay
Yemen	Gabon	Denmark	Belgium	Maldives	Uruguay
Syria			Greece	Bangladesh
Jordan			Czech Republic	Mayanmar
Cyprus			Portugal	Taiwan
			Hungary	Cambodia
			Albania
			Austria
			Switzerland
			Slovakia
			Finland
			Ireland
			Croatia
			Slovenia
			Malta