Screwed Flanges

This flange is referred to as either threaded or screwed. It is used to connect other threaded components in low pressure, non-critical applications.

The various types of thread flange are as follows:

• Plain Threaded Flanges
• Female Threaded Flanges
• Male Threaded Flanges

No welding is required.

 

Types of Screwed Flanges

Standards, Dimensions & Weight

• ANSI/ASME B16.5 Class 150 TH
• ASME/ANSI B16.5 Class 300 TH
• ASME/ANSI B16.5 Class 600 TH
• ASME/ANSI B16.5 Class 900 TH
• DIN 2565 PN6
• DIN 2566 PN10

Threaded Pipe Flange can be used in very high pressure services and their major advantage is that they can be assembled without welding.

Uses of threaded flanges :

Threaded flanges are threaded in the bore which match an external thread on the pipe. Threaded flanges are used with pipes that have external threads. The benefit of these flanges is that it can be attached without welding.

• Thread Steel Fitting can be fitted to pipes of various sizes without welding and this is one chief benefit for which these flanges are highly demanded.
• They can be used in extremely high pressure applications, particularly at or near atmospheric temperature, where the necessary post weld heat treatment is not possible.
• They are ideal for small diameter piping applications.
• They are economical and time saving devices.
• These Threaded Fittings are normally designed for non-cyclic applications.
• The flanges are suitable to be used in applications where welding is hazardous.
• They can be used in highly explosive areas.

Details of Thread Pipe Fitting flange

They are the special type of pipe flanges which can be attached to the pipe without welding. 

1. Threaded flange 2. Thread 3. Pipe or Fitting

Threaded flanges are often used for small diameter, high pressure requirements. thread flanges with a hub have published specifications that range from 1/2″ thru 24″. 

Size: 1/2" to 60", DN 12mm to DN 1500mm 

Pressure class: Class 150 to Class 2,500, PN 2.5 to PN 250

Facing: RF / RTJ

Material:

Cabon steel fitting: A105, A350 LF2

Stainless steel Pipe Flange: A182 F304/F304L/F316/F316L/F321

Alloy steel fitting: F11, F12

Type:Threaded Flanges, TH Flanges, Plain threaded flanges, Female threaded flanges, Male threaded flanges

Packing: plywood case and plywood pallet

ASME/ANSI B16.5 Class 150 TH

Nominal Pipe Size	Outside Diameter of Flange	Diameter of Raised Face	Thickness of Flanges Min.	Diameter of Hub	Length Through Hub	Thread Length Threaded Min.	Bore	Diameter of Bolt Circle	Diameter of Bolt Holes	Number of Bolts	Approximate Weight kgs
NPS	O	R	tf	X	Y	T	B	W	I	n
1/2	90	34.9	9.6	30	14	16	22.2	60.3	15.9	4	0.41
3/4	100	42.9	11.2	38	14	16	27.7	69.9	15.9	4	0.59
1	110	50.8	12.7	49	16	17	34.5	79.4	15.9	4	0.82
1 1/4	115	63.5	14.3	59	19	21	43.2	88.9	15.9	4	0.99
1 1/2	125	73.0	15.9	65	21	22	49.5	98.4	15.9	4	1.28
2	150	92.1	17.5	78	24	25	61.9	120.7	19.1	4	2.01
2 1/2	180	104.8	20.7	90	27	29	74.6	139.7	19.1	4	3.41
3	190	127.0	22.3	108	29	30	90.7	152.4	19.1	4	3.88
3 1/2	215	139.7	22.3	122	30	32	103.4	177.8	19.1	8	4.80
4	230	157.2	22.3	135	32	33	116.1	190.5	19.1	8	5.45
5	255	185.7	22.3	164	35	36	143.8	215.9	22.2	8	6.22
6	280	215.9	23.9	192	38	40	170.7	241.3	22.2	8	7.57
8	345	269.9	27.0	246	43	44	221.5	298.5	22.2	8	12.42
10	405	323.8	28.6	305	48	49	276.2	362.0	25.4	12	16.47
12	485	381.0	30.2	365	54	56	327.0	431.8	25.4	12	26.80
14	535	412.8	33.4	400	56	57	359.2	476.3	28.6	12	35.21
16	595	469.9	35.0	457	62	64	410.5	539.8	28.6	16	44.61
18	635	533.4	38.1	505	67	68	461.8	577.9	31.8	16	49.19
20	700	584.2	41.3	559	71	73	513.1	635.0	31.8	20	62.62
24	815	692.2	46.1	663	81	83	616.0	749.3	34.9	20	88.23



It also provides easy access for cleaning, inspection or modification. Flanges are usually welded or screwed. Pipe flanged joints are made by bolting together two flanges with a gasket between them to provide a seal.

Materials for Flanges

Pipe flanges are manufactured in all the different materials like stainless steel, cast iron, aluminium, brass, bronze, plastic etc. but the most used material is forged carbon steel and have machined surfaces.

In addition, flanges, like fittings and pipes, for specific purposes sometimes internally equipped with layers of materials of a completely different quality as the flanges themselves, which are "lined flanges".

The material of a flange, is basically set during the choice of the pipe, in most cases, a flange is of the same material as the pipe.

All flanges, discussed on this website fall under the ASME en ASTM standards, unless otherwise indicated. ASME B16.5 describes dimensions, dimensional tolerances etc. and ASTM the different material qualities.

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