The sealing problem of flat welding flanges has always been a hot issue related to the production cost or economic benefits of enterprises. Therefore, the sealing principle of flat welding flanges has been improved and perfected. However, the main design disadvantage of the flat welding flange is that it cannot guarantee no leakage. This is a design defect: The connection is dynamic, and periodic loads, such as thermal expansion and fluctuating loads, will cause the flange surfaces to move each other and affect the function of the flange, thereby damaging the integrity of the flange and eventually leading to leakage.

The sealing principle of the flat welding flange: The two sealing surfaces of the bolt squeeze the flange gasket to form a seal, but this will also cause the seal to be damaged. In order to maintain the seal, you have to maintain a huge bolt force. In order to do this, you have to make the bolt bigger. Larger bolts are matched with larger nuts, which means that larger bolt diameters are required to create conditions for tightening the nuts. However, the larger the diameter of the bolt, the flange will bend, and the only way is to increase the wall thickness of the flange part. The entire device will require a huge size and weight, which becomes a special problem in offshore environments, because in this case weight is always the main issue that people must pay attention to. Moreover, fundamentally speaking, flat-welded flanges are an ineffective seal. It requires 50% of the bolt load to be used for extruding the gasket, while only 50% of the load used to maintain pressure is left. Flat welding flanges are often used when the medium temperature and pressure are not high and the medium is corrosive. When the medium is corrosive. The rare integral flanges include flat welding flanges and butt welding flanges. Flanged pipe fittings refer to pipe fittings with flanges (lugs or connecting plates). It can be made by casting. The flat welded flange is mainly a part that connects the pipe to the pipe. According to the structure type. It can also be formed by threaded connection or welding. Flange connection refers to a pair of flanges, a gasket and several bolts and nuts.

Features of flat welding flange:

    The flat welded flange not only saves space and weight, but more importantly, it ensures that the joints will not leak and have good sealing performance. The size of the compact flange is reduced due to the reduced diameter of the seal, 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 compress the cover tightly. As the required pressure decreases, the size and number of bolts can be reduced accordingly, so the final design is small and light (70% to 80% lighter than the weight of traditional flanges). product. 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 use. However, the main design disadvantage of the flat welding flange is that it cannot guarantee no leakage. This is the shortcoming of its design: the connection is dynamic, and cyclical loads such as thermal expansion and fluctuations will cause movement between the flange surfaces, affecting the function of the flange, and thus the integrity of the flange, which will eventually lead to leakage. It is impossible for any product to be defect-free, but try to control the shortcomings of the product to the minimum, so the company tries to improve the performance of the product as far as possible in the production of flat welded flanges to make it play the greatest role.