The potential problem of the combination of carbon steel flange and stainless steel bolt is that the potential difference between the two is large, there is a risk of galvanic corrosion, and the corrosion of the carbon steel side is accelerated. When used at high temperature (temperature greater than 200), there is no electrolyte and no galvanic corrosion. At room temperature, corrosion from climate, rain, etc. must be considered, but considering that the area of ??the flange is much larger than that of the bolt, the problem is not big.