What are marine flanges?
What are marine flanges?
On the ship, there are piping systems everywhere, just like the blood vessels of the human body, which guarantees the normal operation of the ship, so what kind of connection are used for these densely packed pipelines like blood vessels? Today I will introduce one of the most commonly used marine connectors: marine flanges.
Marine flange is a kind of flange used on ships or marine. Flange is a part that connects pipe and pipe to each other. Connect to the pipe end. There are holes on the marine flanges and bolts can be used to make the two flanges tightly connected. The flanges are sealed with gaskets.
Flange connection is to fix two pipes, pipe fittings or equipment on a flange plate respectively, add flange pads between the two flange plates, and fasten them together with bolts to complete the connection. Some pipe fittings and equipment have their own flanges, which are also flange connections.
Types of marine flanges
Marine flat welding flange
It is a flange welded by inserting the pipe into the inner ring of the flange. The flat welding flange is divided into two types: the neck flat welding flange and the plate lap welding flange.
The advantages of flat welding flanges are simple manufacture and low production cost, but they are not resistant to high temperature and high pressure. They are mainly used for normal temperature pipelines with pressures lower than 2.5 MPa. They are the most widely used flanges on ships.
Marine butt welding flange
Also known as high-neck flange, it refers to a flange with a neck that has a round pipe transition and is butt welded to the pipe.
The butt-welded flange has high rigidity and is not easy to deform, has good sealing, and is widely used. It is suitable for occasions with high pressure and temperature. The nominal pressure PN is about 16MPa. Mainly used for compressed air piping system and carbon dioxide piping system.
Marine loose flange
Also known as lap joint flanges, pipes are generally made of high-cost materials. In order to reduce costs, internal connections of the same material as the pipes and flanges of different materials are used, which is to use flanges, steel rings, etc. On the pipe end, the flange can move on the pipe end.
Loose flanges are generally used on copper-nickel alloy pipes and expansion joints.
Marine hydraulic flange (SAE Flange)
The pressure of the ship’s hydraulic piping system is very high, so special socket type high pressure method flanges are used. The flange thickness is about 30mm-45mm depending on the pipe diameter. SAE Flange generally uses a concave flange and a convex flange to connect method, use O-ring as sealing material. (For details, please click: What is a SAE flange?)
Standard for marine flanges
About the standard codes of marine flanges:
ISO International Standard/GB National Standard
- GB2503-89 National Standard Marine Cast Iron Flange (Quad Position)
- GB2504-89 National Standard Marine Cast Steel Flange (Quad Position)
- GB2505-89 National Standard Marine Cast Copper Flange (Quad Position)
- GB2506-89 National Standard Marine Lap Welded Steel Flange (Quad Position)
- GB2507-89 National standard marine lap welded copper flange (quad)
- GB2508-89 National standard marine lap welded steel ring loose steel flange (four-position)
- GB/T4450-1995 National Standard Marine Blind Steel Flange
- GB10746-89 National Standard Marine Butt Welding Steel Flange (Quad Position)
- GB10747-89 National Standard Marine Butt Welding Steel Ring Loose Steel Flange (Quad Position)
- GB10748-89 National Standard Marine Welded Copper Ring Loose Steel Flange (Quad Position)
- GB10749-89 National Standard Marine Copper Pipe Folded Loose Steel Flange (Quad Position)
- GB10750-89 National standard marine oblong cast iron and cast steel flanges
- GB10751-89 National Standard Marine Flat Welded Steel Flange
CB Soviet Standard/Industry Standard
- CB/T43-1999 National Standard Marine Cast Iron Flange
- CB/T44-1995 National Standard Marine Cast Steel Flange
- CB/T45-1999 national standard marine cast copper flange
- CB/T46-1999 National Standard Overlap Welded Steel Flange
- CB/T47-1999 national standard butt welding steel flange
- CB/T48-1999 national standard welded copper flange
- CB/T49-1999 national standard lap welded steel ring loose steel flange
- CB/T50-1999 national standard butt welded steel ring loose steel flange
- CB/T51-1999 National standard lap welding copper ring loose steel flange
- CB/T52-1999 national standard copper pipe flanged loose steel flange
- CB856-76 national standard P30 cast steel flange
- CB857-76 national standard P30 cast copper flange
- CB858-76 GB P30 welding copper flange
- CB859-76 GB P30 welded steel flange
- CB1044-83 National standard P30 different diameter lap welded copper flange
- CB1045-83 National standard P30 copper flange with different diameter lap welding
- CB1144-85 GB P30 blind steel flange
- CB*3212-1999 National standard marine lap welding, butt welding, brazing flange loose sleeve reducing steel flange
- CB/T3766-1996 national standard exhaust pipe steel flange and gasket
- CB/T3846-1999 National standard marine aluminum pipe flanged loose sleeve aluminum flange
- CB/T3847-1999 National Standard Marine Flat Welded Steel Flange
- CB/T3848-1999 GB oblong cast iron and main steel flange
- CB/T3847-1999 marine oblong welding flange
JIS Japanese Standard/CBM Foreign Trade Standard
- CBM1004-81 Japanese standard PN0.2MPa cast iron, cast steel, lap welded steel flange
- CBM1005-81 Japanese standard PN0.5MPa cast iron, cast steel flange
- CBM1006-81 Japanese standard PN1.0MPa cast iron, cast steel flange
- CBM1007-81 Japanese standard PN1.6MPa cast iron, cast steel flange
- CBM1008-81 Japanese standard PN2.0MPa cast steel flange
- CBM1009-81 Japanese standard PN3.0MPa cast steel flange
- CBM1010-81 Japanese standard PN4.0MPa cast steel flange
- CBM1011-81 Japanese standard PN6.3MPa cast steel flange
- CBM1012-81 Japanese standard PN0.5MPa lap welded steel flange
- CBM1013-81 Japanese standard PN1.0MPa lap welded steel flange
- CBM1014-81 Japanese standard PN1.6MPa lap welded steel flange
- CBM1015-81 Japanese standard PN2.0MPa lap welded steel flange
- CBM1016-81 Japanese standard PN3.0MPa lap welded steel flange
- CBM1017-81 Japanese standard PN3.0MPa butt welding steel flange
- CBM1018-81 Japanese standard PN4.0MPa butt welding steel flange
- CBM1019-81 Japanese standard PN6.3MPa butt welding steel flange
- CBM1020-81 Japanese standard PN0.5, 1.0, 1.6MPa cast copper, lap welded copper flange
- CBM1021-81 Japanese standard exhaust pipe steel flange
Size of marine flanges
- DN15 – DN1500
Wall thickness of marine flanges
- SCH10 – SCH160
Material of marine flanges
- Carbon steel: ASTM A105, A350 LF2, etc.
- Stainless steel: ASTM A182 F304, F304L, F316, F316L, F321, F347, F310, F44, F51, etc
- Alloy steel: ASTM A182 F1, F5, F9, F11, F22, F91, ASTM A694 F42, F46, F52, F56, F60, F65, F70, etc.
The scope of application of marine flanges
Because of the good comprehensive performance of the ship standard flange, it is widely used in basic projects such as chemical industry, construction, water supply, drainage, petroleum, light and heavy industry, refrigeration, sanitation, plumbing, fire fighting, electric power, aerospace, shipbuilding and so on.
Source: China Marine Flange Manufacturer – Yaang Pipe Industry (www.steeljrv.com)
(Yaang Pipe Industry is a leading manufacturer and supplier of nickel alloy and stainless steel products, including Super Duplex Stainless Steel Flanges, Stainless Steel Flanges, Stainless Steel Pipe Fittings, Stainless Steel Pipe. Yaang products are widely used in Shipbuilding, Nuclear power, Marine engineering, Petroleum, Chemical, Mining, Sewage treatment, Natural gas and Pressure vessels and other industries.)
If you want to have more information about the article or you want to share your opinion with us, contact us at sales@steeljrv.com
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