Main causes of Blowhole in submerged arc welding

In the air separation unit, low-temperature liquid is transported by centrifugal cryogenic pump. In order to ensure the reliable operation of the equipment, two sets of low-temperature pumps are generally equipped, one for use and one for standby. During normal operation, the main pump runs at full load, and the standby pump is in standby state under low load operation. Since the working medium temperature of cryogenic liquid pump is about -180°C, the working pressure is very high, and the pump body is installed in the cold box. When the pump fails, it is extremely difficult to maintain. Therefore, how to maintain the stable and reliable operation of cryogenic liquid pump is of great significance.

The brief introduction of the air filter and air compressor in this process is the same as that of the chilled nitrogen production process. 1. Cold dryer: it is an air separation equipment used to reduce the temperature of compressed air before entering the air drying purifier to extract oil and water. It usually adopts post cooler with the structure of column pipe type, casing type, cooling sheet type and so on. 2. Oil-water separator: its function is to separate the oil and moisture contained in the compressed air and make the compressed air get Primary purification. 3. Air drying purifier: Compressed air still contains certain moisture after passing through the post cooler, and its content depends on the temperature of the air. The drying process of compressed air generally adopts molecular sieve absorption method and freeze drying method. 4. Pressure conversion absorption nitrogen generation device: the adsorbents used are usually 5A Molecular sieve or carbon molecular sieve, an...