Stainless steel flange, also know as stainless steel pipe flange, which are used to connect pipes. It can be divided as threaded flanges and welding flanges.

Flange is a disk-shaped parts, the most common in the pipeline project, flanges are paired and the mating flange on the valve used. In the pipeline project, flanges used to connect pipes. The need to connect pipes, various mounting a flange, low-pressure pipe can be used silk flange, the use of four kilograms or more pressure welding flanges. Between the two flange gaskets, then bolted. Different pressures flange have different thickness and different use of bolts.

Pumps and valves, and when the pipe connections, these local facilities and equipment, also made the corresponding flange shape, also known as the flange connection. All in two planes at the same time surrounding the use of bolted closed parts, generally known as the “flange”, such as ventilation pipe connections, this type of parts can be called “flange parts.” But this is only a partial connection device, such as flange connections and pumps, on the bad pumps called “flange parts.” Relatively small, such as valves, etc., can be called “flange parts.”

A gasket capable of plastic deformation, and has a certain strength of the ring material. Most non-metallic gaskets are cut from the plate down, according to the factory or by a professional sized, the material is asbestos rubber sheet, asbestos, polyethylene panels; also useful for sheet metal (tin, stainless steel) asbestos other non-metallic materials wrapped package gasket made of metal;

There is also a strip along winding made of spiral wound gasket with a thin strip of asbestos. Common rubber gasket suitable for temperatures below 120 ℃ of occasions; asbestos rubber gasket suitable for steam temperature is lower than 450 ℃, the temperature of the oil is lower than 350 ℃, a pressure less than 5MPa occasion, general corrosion medium, most commonly used acid asbestos. In the high-pressure equipment and piping, copper, aluminum, steel on the 10th, the lens type or other shaped metal gasket made of stainless steel. Contact width high pressure gasket sealing surface is very narrow (line contact), the gasket sealing surface and high finish machining.

Low voltage small diameter wire flange, high and low pressure large diameter are using welding flange thickness and bolt diameter and number of connecting different pressures flange is different.

  1. connecting pipe and holding pipe sealing performance;
  2. to replace certain pipeline;
  3. to open and inspect the pipe line;
  4. to facilitate the closure of certain pipeline.

Size: 1/2 “~ 80” (DN10-DN5000)
Pressure rating: 0.25Mpa ~ 250Mpa (150Lb ~ 2500Lb)
Common Criteria:
GB: GB9112-88 (GB9113 · 1-88 ~ GB9123 · 36-88)
American Standard: ANSI B16.5, ANSI 16.47 Class150,300,600,900,1500 (TH, LJ, SW)
Japanese standard: JIS 5K, 10K, 16K, 20K (PL, SO, BL)
German standard: DIN2527,2543,2545,2566,2572,2573,2576,2631,2632,2633,2634,2638
(PL, SO, WN, BL, TH)
Italian standard: UNI2276,2277,2278,6083,6084,6088,6089,2299,2280,2281,2282,2283
(PL, SO, WN, BL, TH)
British Standard: BS4504,4506
Ministry of Chemical Industry Standard: HG5010-52 ~ HG5028-58, HGJ44-91 ~ HGJ65-91
HG20592-97 (HG20593-97 ~ HG20614-97)
HG20615-97 (HG20616-97 ~ HG20635-97)
Machinery of the standard: JB81-59 ~ JB86-59, JB / T79-94 ~ JB / T86-94
Pressure Vessel: JB1157-82 ~ JB1160-82, NB / T47020-2012 ~ NB / T47027-2012
Marine Flange Standard: GB / T11694-94, GB / T3766-1996, GB / T11693-94, GB10746-89, GB / T4450-1995, GB / T11693-94, GB573-65, GB2506-89, CBM1012-81 , CBM1013 etc.
Flange production standard
GB: GB / T9112-2010 (GB9113 · 1-2010 ~ GB9123 · 4-2010)
Ministry of Chemical Industry Standard: HG5010-52 ~ HG5028-58, HGJ44-91 ~ HGJ65-91, HG20592-2009 series, HG20615-2009 series
Machinery of the standard: JB81-59 ~ JB86-59, JB / T79-94 ~ JB / T86-94, JB / T74-1994
Pressure Vessel: JB1157-82 ~ JB1160-82, JB4700-2000 ~ JB4707-2000 B16.47A / B B16.39 B16.48

  • Plate flat welding flange
  • With neck flat welding flange
  • Weld neck flange
  • Socket welding flange
  • Threaded flange
  • Flange cover
  • Weld neck ring loose flange
  • Flat welding ring loose flange
  • Ring groove flange and flange cover
  • Large-diameter flange plate
  • Large-diameter high-neck flange
  • Blind character
  • Loose flange welded ring
  • Rotating flange
  • Anchoring flange
  • Welding / welding flange cover
  1. In order to prevent the heat generated between the eyes corrosion, welding current should not be too large, less than about 20% of the carbon steel electrode, the arc should not be too fast cooling between the layers to narrow weld appropriate.
  2. The use of electrodes should be kept dry, titanium calcium type should be dried 150 ℃ 1 hour a low hydrogen type shall be dried 200-250 ℃ 1 hours (can not be repeated drying, easy to crack or the coating peeled off) to prevent electrode coating viscous oil and other dirt, so as not to cause the weld to increase the carbon content and impact of the quality of the weldment.
  3. Stainless steel welded pipe flanges, subjected to repeated heating carbide precipitation, reduce corrosion resistance and mechanical properties.
  4. Chromium stainless steel flanged fittings after welding sclerosing American Standard flange large, easy to crack. If after using the same type of chromium stainless steel electrode (G202, G207) welding must be above 300 ℃ preheating and welding slow cooling process of about 700 ℃. If the weldment after weld heat treatment is not possible, it should be made of stainless steel flanged fittings electrode (A107, A207).
  5. Stainless steel flanges, to improve corrosion resistance and weldability and appropriately increase the stability of an appropriate amount of elements Ti, Nb, Mo, etc. and weldability compared with the chromium stainless steel flange better. When using the same type of chromium stainless steel flange electrode (G302, G307), it should be tempered after more than 200 ℃ preheating and welding of around 800 ℃. If you can not heat treated weldments should be made of stainless steel flanged fittings electrode (A107, A207).
  6. Stainless steel pipe flanges, welded flange welding rod has good corrosion resistance and oxidation resistance, widely used in chemical, fertilizer, petroleum, medical machinery.

304, 304l, 316, 316l, 321 etc.

GB flange English (National standard flange) refers to the People’s Republic of China national standards “GB / T 9112 ~ 9124-2010 steel pipe flanges” requirement produced flange piece.
GB flange standards by the State Administration of Quality Supervision, Inspection and Quarantine and the People’s Republic of China Standardization Administration of China jointly issued on 2011-01-10, 2011-10-01 from the recommended standards implemented since.
GB / T 9112 ~ 9124-2010 total includes the following 13 criteria:
Instead of GB GB / T9112-2000; GB / T10745-1989 standard
GB / T 9112-2010 Types and parameters for steel pipe flanges
GB / T 9113-2010 Integral steel pipe flanges
GB / T 9114-2010 with a neck steel pipe flanges
GB / T 9115-2010 welded steel pipe flanges
GB / T 9116-2010 with a neck flat welded steel pipe flanges
GB / T 9117-2010 with a neck socket welding steel pipe flanges
GB / T 9118-2010 welded ring Loose hubbed steel pipe flanges
GB / T 9119-2010 plate flat welding steel pipe flanges
GB / T 9120-2010 butt Loose plate steel pipe flanges
GB / T 9121-2010 Loose plate flat welding steel pipe flanges
GB / T 9122-2010 flange Loose plate steel pipe flanges
GB / T 9123-2010 Steel pipe blank flanges
GB / T 9124-2010 steel pipe flanges
Technical conditions
This standard specifies pressure marks into PN and Class mark mark.
PN 12 pressure rating marked with
Respectively: PN2.5; PN6; PN10; PN16; PN25; PN40; PN63; PN100; PN160; PN250; PN320; PN400
Class labeled with six pressure levels
They are: Class 150; Class 300; Class 600; Class 900; Class 1500; Class 2500

Another meaning of GB flange: In accordance with the requirements of national standard dimensions, tolerances and other production flange, different from the standard sizes not manufactured piece flange, also known as two standard flange (someone called non-standard flange is incorrect), usually some unscrupulous businesses will reduce the flange thickness, diameter two dimensions to achieve the purpose of saving material, as well as with scrap steel or scrap steel processing flange, usually this steel chemical composition and mechanical performance is not up to the waste or, worse, with black steel flange private steel production, steelmaking technologies such private obsolete steelmaking use can not guarantee the mechanical properties and weldability, and can not be possible when using steel welding, or steel itself for cracks, holes and other leaks will go up after welding. So try to use the time of purchase flange GB flange. If we must look closely at funding a limited selection of two standard flanges and measures the size of the flange so as not to be fooled.

ASME / ANSI B 16.5ASME / ANSI B 16.47
Welding Neck Flange
Slip On Flange
Blind Flange
High Hub Blind Flange
Socket Weld Flange
Lap Joint Flange
Threaded Flange
Ring Type Joint Flange
   Welding Neck Flange
Blind Flange (Series A & B)
150 LBS
300 LBS
400 LBS
600 LBS
900 LBS
1500 LBS
2500 LBS
75 LBS
150 LBS
300 LBS
400 LBS
600 LBS
900 LBS
ASME / ANSI B 16.36BS 4504 SEC 3.1
(Orifice Flanges)  Welding Neck Flange
Slip On Flange
Threaded Flange
Welding Neck Flange (111/134)
Hubbed Slip On Flange (112)
Hubbed Threaded Flange (113)
Lapped Pipe End Flange (133)
Plate Flange (101)
Loose Plate Flange (102)
Loose Plate with Weld Neck Flange (104)
Blank Flange (105)
300 LBS
400 LBS
600 LBS
900 LBS
1500 LBS
2500 LBS
PN 2.5 TO PN 100
DIN 2527
DIN 2566
DIN 2573
DIN 2576
DIN 2641
DIN 2642
DIN 2655
DIN 2656
DIN 2566
DIN 2627
DIN 2628
DIN 2629
DIN 2631
DIN 2632
DIN 2633
DIN 2634
DIN 2635
DIN 2636
DIN 2637
DIN 2638
DIN 2673
Plate Flange (01)
Loose Plate Flange (02, 03, 04)
Blind Flange (05)
Welding Neck Flange (11)
Hubbed Slip On Flange (12)
Screwed Flange (13)
Hubbed Socket Welding Flange (14)
Loose Hubbed Flange (15)
Integral Flange (21)
PN 6 TO PN 100ISO-PN 2.5 TO PN 40
Pr EN 1092-1 Flanges
Plate Flange (01)
Loose Plate Flange (02, 04)
Blind Flange (05)
Welding Neck Flange (11)
Hubbed Slip On Flange (12)
Screwed Flange (13)
Integral Flange (21)
ISO-PN 2.5 TO PN 100


Stainless Steel: 304 / 304L / 304H / 316 / 316L / 316H/ 316TI / 317 / 317H / 321 / 321H / 347 / 347H
Duplex/Super Duplex Stainless Steel: F44 / F45 / F51 / F53 / F55 / F61

WNR 1.4541, WNR 1.4571, WNR 1.4301, WNR 1.4306, WNR 1.4307, WNR 1.4401, WNR 1.4404, WNR 1.4438, WNR 1.4462

BF Z 3 CN 19-09, BF Z 7 CN 18-09, BF Z 6 CNT 18-10, BF Z 3 CND 17-11-02, BF Z 7 CND 17-11-02, BF Z 6 CNDT 17-12, BF Z 6, CNDNb 18-12