Characteristics and sealing principle of flat welding flange

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2023-06-13 09:58

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A flat-welded flange is a flange that is connected to a vessel or pipe by fillet welding. It can be any flange. According to the integrity of the flange ring and straight barrel section at the time of design, check the integral flange or loose flange respectively. The ring of flat welding flange has two kinds of neck and non neck. Compared with the neck welding flange, the flat welding flange has a simple structure and less material, but its rigidity and sealing performance are not as good as the neck welding flange. Flat welded flanges are widely used in the connection of medium and low pressure vessels and pipelines.

Flat welding flange not only saves space and weight, but more importantly, it ensures that the joint will not leak and has good sealing performance. Due to the reduction of the diameter of the seal, the size of the compact flange is reduced, which will reduce the cross section of the sealing surface. Secondly, the flange gasket has been replaced by a sealing ring to ensure that the sealing surface matches the sealing surface. In this way, only a small amount of pressure is required to tightly compress the lid. As the required pressure decreases, the size and number of bolts can be reduced accordingly. Therefore, a new type of flat welding flange with small size and light weight (70% to 80% lighter than traditional flanges) is designed. Therefore, the flat welding flange type is a relatively high-quality flange product, which reduces the quality and space, and plays an important role in industrial applications.

The sealing principle of flat welding flange: the two sealing surfaces of the bolt squeeze the flange gasket and form a seal, but this can also cause damage to the seal. In order to maintain the seal, a large bolt force must be maintained. Therefore, the bolt must be made larger. Larger bolts must be matched with larger nuts, which means that larger diameter bolts are required to create conditions for tightening the nuts. However, the larger the bolt diameter, the applicable flange will bend.

The method is to increase the wall thickness of the flange portion. The entire equipment will require huge size and weight, which becomes a special problem in the offshore environment, because in this case, the weight of the flat welded flange is always the main problem that people must pay attention.

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Characteristics of butt welding flanges

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Characteristics of butt welding flanges

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2023-06-13

Stainless steel flanges are flanges that extend steel pipes, pipe fittings, etc. into the flanges and are connected to equipment or pipelines through fillet welds. The inner hole on one side of the flange is provided with a welding boss, and the welding boss is provided with an inner hole. The inner hole communicates with the inner hole in the center of the flange, and there is elasticity between the flange and the welding boss. The two top surfaces of the elastic ring are respectively combined with the flange and the welding boss. There are many screw holes on the flange. The screw holes are symmetrically distributed around the center of the flange. The stainless steel flange is made of stainless steel, followed by a polyethylene plastic layer, a rubber layer and a PVC layer. Here we take a look at the use of stainless steel flange precautions. 1. In order to prevent corrosion between eyes caused by heating of stainless steel flanges, the welding current should not be too large, about 20% less than carbon steel electrode, the arc should not be too long, the cooling speed is between the number of layers, and the narrow bead effect is better.

Advantages and disadvantages of flat welding flange

2023-06-13

Flat welded flanges are mainly used for gas valves and natural gas pipelines. Because the short neck can improve the rigidity and carrying capacity of the flange. Flat welded flanges are used for general media. Flat welding flange with neck is suitable for flammable, explosive, corrosive and toxic places. The sealing surface of flat welding flange can be convex surface, concave convex surface and tongue and groove surface. They are different in structure, sealing effect and strength. Flat welding flange is generally called flat plate, also known as lap welding flange. The connection between the flat welding flange and the pipe is to insert the pipe into the flange inner hole to the appropriate position before the lap welding. The characteristics of flat welding flange: flat welding flange not only saves space, reduces weight, but also ensures no leakage at the joint and good sealing performance. The reason for the reduced size of the compact flange is the reduced diameter of the seal, which will reduce the cross section of the sealing surface. The advantages of flat welding flanges are as follows:

Applicable scope and purpose of welding flange