Carbon steel flange buying guide


carbon steel butt weld flange refers to a flange with a neck that is butt welded to the pipe. It is a kind of disc-shaped part used in pairs, and the most common type of flange in piping work that is mainly used for the connection of pipelines. When installing, the two flanges are sealed and then tightened with screws. The flanges with different pressures are of different thicknesses and used with different screws. 

The heat resistant property of the carbon steel flange is indicated as follows.
1. High impact resistance — The impact strength of carbon steel flanges is significantly improved compared with other kinds.
2. The storage time of carbon steel flanges is relatively long. — They are UV resistant, radiation-proof, anti-fade, and can be stored for more than 50 years.
3. Carbon steel flanges have good corrosion resistance. — Apart from a small amount of hydrogenation agent, they can withstand a variety of chemical media corrosion. The flanges have a particularly good strong acid, alkali, corrosion resistance.
4. The heat transfer coefficient of carbon steel flanges at room temperature is 46.5 W/mK.

The carbon steel flange joint should maintain on the same axis, and the center deviation of the screw hole should not exceed 5% of the hole diameter. The coupling screws of the carbon steel flange should be of the same specification, with the same installation direction, and the screws should be evenly distributed when tightening. A diagonal washer with unequal thickness cannot be used to remedy the unfairness of the carbon steel flange, neither can the double washers. When large-diameter gaskets are required to be spliced, they should not be flat welded but they can be slanted or processed by other methods. In order to facilitate the installation and uninstallation of carbon steel flanges and fastening screws, the shortest distance between the carbon steel flange and the wall surface should not be less than 200 mm. The screws should be tightened crosswise and in turn.

Some unscrupulous manufacturers will reduce the thickness and outer diameter of the flange to save materials. They also use offcut steel to process the flanges, which are sure to be with unqualified chemical composition and mechanical properties and cannot guarantee the performance or even be unable to connect to pipes properly. Poor steel materials will also cause leakage. Therefore, when buying flanges, it is better to pick carbon steel flanges from legitimate suppliers.