What are the precautions for using flat welding flanges?
Posted by Admin | 07 Mar
What are the precautions for using flat welding flanges?
Features of flat welding flange: Flat welding flange not only saves space and weight, but also importantly, the joint does not leak and has good sealing performance. Due to the reduced diameter of the seal, the size of the compact flange is reduced, which will reduce the cross-section of the sealing face. Second, the flange gasket has been replaced by a sealing ring to seal the mating sealing surface. In this way, only a small amount of pressure is required to compress the cap tightly. As the required pressure is reduced, the size and number of bolts can be correspondingly reduced, so a new type of small size, lightweight (70% to 80% lighter than traditional flanges) is finally designed. product. Therefore, the flat welding flange type is a comparative flange product, which reduces the quality and space, and plays an important role in industrial applications.
The main design disadvantage of flat welded flanges is that they cannot be leak-free. This is a disadvantage of its design: the connection is dynamic, and cyclic loads (such as thermal expansion and fluctuations) will cause movement between the flange surfaces, affecting the function of the flange, which in turn affects the integrity of the flange, ultimately leading to leaks . No product can be free of defects, but the deficiencies of the product should be controlled as much as possible. Therefore, the company will try its best to improve the product performance in the production of flat welding flanges to play an important role.
The sealing principle of the flat welding flange: the two sealing surfaces of the bolt squeeze the flange gasket and form a seal, but this will also cause the seal to be damaged. In order to maintain the seal, a huge bolt force must be maintained, therefore, the bolts must be made larger. Large bolts must match large nuts, which means a large diameter bolt is required to allow for tightening of the nut. However, the larger the diameter of the bolts, the more bendable flanges are applicable. The solution is to increase the wall thickness of the flange section. The size and weight of the entire device will be a particular issue in an offshore environment, where weight is always the main issue. And, fundamentally, flat welded flanges are ineffective seals. It requires 50% of the bolt load to squeeze the washer, leaving only 50% to hold the pressure.