1. What is a loose flange?

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The loose flange is the movable flange piece, which is generally matched with the water supply and drainage fittings (the most common on the expansion joint). When the factory leaves the factory, there is a flange at each end of the expansion joint, which is directly connected to the pipeline, The equipment is connected by bolts.

2. How is the flange connected to the pipe?

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There are many types of flanges. Generally, flat flanges, butt welding flanges (long neck flanges), loose flanges, etc. are used. Flat-welded flanges are used for medium and low pressure, using plug welding and welding on both sides. The welding depth is 2-5mm from the flange sealing surface. Butt-welding flanges can be butt-welded directly, and the loose flange bolt connection does not need welding.

3. What does flange type mean?

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The flange is a link that connects the valve and the pipeline, that is, when the valve is connected to the pipeline, the connection is connected by bolts, so the two ends of the valve with N uniformly distributed bolt holes are flanged.
Flange: means something or part with a flange. This part can be a single flange, or a combined type, such as a pipe with flanges on one or both ends, and there are several on the flange. Through holes are used to install screws. Some bearings have flanges on the outer ring. This flange can have holes or no holes and is only used for rib positioning.
Flange type: The connection between the valve and the pipeline or machinery and equipment adopts a flange connection, which is generally called the flange type.

4. What is a flange?

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Flange is a disc-shaped part, which is the most common in pipeline engineering. Flanges are used in pairs. In pipeline engineering, flanges are mainly used for pipeline connection. In the pipelines that need to be connected, a flange plate is installed in various ways. The low-pressure pipeline can use the wire connection flange, and the welding flange is used for the pressure above 4 kg. Add a sealing point between the two flanges, and then tighten them with bolts. Flanges with different pressures have different thicknesses and use different bolts. When water pumps and valves are connected to pipelines, parts of these equipments are also made into corresponding flange shapes, also known as flange connections. All connecting parts that are connected by bolts on the periphery of two planes and are closed at the same time are generally called "flanges", such as the connection of ventilation pipes. This type of parts can be called "flange parts". But this kind of connection is only a part of the equipment, such as the connection between the flange and the water pump, it is not good to call the water pump "flange parts". Smaller ones, such as valves, can be called "flange parts".

5. What kind of connection is the flange?

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Flange connection is an important connection method for pipeline construction. 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. The flange is divided into threaded connection (wire connection) flange and welding flange. Low-pressure small-diameter wire flanges, high-pressure and low-pressure large-diameters both use welded flanges. The thickness of flanges and the diameter and number of connecting bolts are different for different pressures.
According to different levels of pressure, flange gaskets also have different materials, ranging from low-pressure asbestos gaskets, high-pressure asbestos gaskets to metal gaskets.
The flange connection is easy to use and can withstand greater pressure. In industrial pipelines, flange connections are widely used. In the home, the pipe diameter is small, and it is low pressure, and the flange connection is invisible. If it is in a boiler room or production site, flanged pipes and equipment are everywhere. 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.
Note that when connecting, especially when the bolts are tightened, make sure that all bolts are tight.

6. What is the use of flanges?

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The flange is used for positioning. For example, there is an installation method of the oil cylinder called flange installation. For example, four symmetrical holes are punched around a cuboid. There is a large hole in the middle and the outer diameter of the cylinder is the same. Put this cuboid on the cylinder and the other can be welded. The way is fixed together, the connection between the oil cylinder and other things is through the four holes around the rectangular parallelepiped. This rectangular parallelepiped can be called a blue.

7. What is the difference between the connection method of the orifice flange and the ordinary flange?

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That is to fix the two pipes, pipe fittings or equipment on a flange respectively, add flange pads between the two flanges, and fasten them together with bolts to complete the connection. Orifice flange is the connection of the orifice plate (the measuring part of the orifice plate flowmeter) to the pipeline on the orifice plate flowmeter. The two-sided flanges fix the orifice plate in the middle, and lead to the differential pressure through the pressure point on the flange. On the transmitter, to measure the flow rate.

8. What problems should be paid attention to during flange installation?

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1. The flange should have sufficient strength and must not be deformed during tightening. The flange sealing surface should be flat and clean, and oil stains and rust spots should be carefully cleaned up during installation.
2. The gasket should have good oil resistance and anti-aging properties, as well as good elasticity and mechanical strength. The installation should select gaskets of different cross-sections and sizes according to the shape of the joints, and place them correctly.
3. The tightening force of the flange should be uniform, and the compression of the rubber pad should be controlled at 1/3.

9. What is the difference between butt welding flange and flat welding flange?

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The butt welding flange has the same pipe diameter and wall thickness as the pipe to be welded, and it is welded like two pipes.
The flat welding flange is a concave platform that is slightly larger than the outer diameter of the pipe at the interface, and the pipe is inserted into it for welding.
Butt welding has better welding performance and less corrosion.
Flat welding and butt welding are the welding methods when flanges and pipelines are connected. When flat welding flanges are welded, only one-sided welding is required. The internal ports of the welding pipeline and flange connections are not required. The welding installation of butt welding flanges requires flanges. Surface welding. Therefore, flat welding flanges are generally used for low and medium pressure pipelines, butt welding flanges are used for connecting medium and high pressure pipelines. Butt welding flanges are generally at least PN2.5MPa. Butt welding is used to reduce stress concentration. Butt welding flanges are mostly neck flanges, also called nipple flanges. Therefore, the installation cost, labor cost and auxiliary material cost of butt welding flange are higher because of one more process.
Not all butt welding flanges need to be welded on both sides inside and outside. Generally, there is only one welding on the outside if there is no special requirement. Have you never seen a 1/2" butt welding flange:), flat welding is better. Ah, because the pipe and the flange are perpendicular to each other, the pipe will not be inclined.

10. What is the difference between flange and valve?

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A valve is the same thing as a faucet, or in other words, a faucet is a kind of valve. It can be unscrewed, and the water or air can flow out; it can be closed, and the water will not flow.
The tap at home is screwed to the pipe, but some pipes used in the factory, the water or gas inside, the pressure is very high, the threaded connection is too weak, they are directly welded or connected by other methods. Flange is one of the connection methods.

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