แผ่น S TEN สำหรับเชื่อมโครงสร้าง และทนการกัดกร่อนได้ดีในกรด ซัลฟูริค และ กรดไฮโดคลอลิค
Recently, environmental issues are becoming pressing concerns. In parallel with this, construction of tall smokestacks, air preheaters, electrostatic precipitators and flue-gas desulfurizers and other treatment equipment has shown great strides.
Meanwhile, the mainstay industrial fuel has shifted from conventional coal to heavy oil, which poses a large problem of corrosion at the low-temperature section of flue-gas treatment equipment (in particular, air preheaters, flues and smokestacks) due to sulfur oxides.
The low-temperature section corrosion is the corrosion caused by high-temperature, highly-concentrated sulfuric acid, called sulfuric acid dew-point corrosion. This kind of corrosion differs from general atmospheric corrosion and causes heavy corrosion of not only ordinary steel but even stainless steel.
Further, because of the remarkable technological developments recently seen in dioxin countermeasures, flue-gas temperatures are increasingly being reduced from previous levels.
In conventional facilities where, formerly, only sulfuric acid dew-point corrosion occurred, there are now cases of hydrochloric acid dew-point corrosion that is caused by lower flue-gas temperatures resulting from remodeling with countermeasures against dioxins.
Developed to solve these problems is S-TEN—steel for welded structures, highly resistant to sulfuric acid and hydrochloric acid dew-point corrosion.
S-TEN 1 has effective resistance to both sulfuric acid dew point corrosion and hydrochloric acid dew point corrosion, while S-TEN 2 is effectively resistant to sulfuric acid dew point corrosion.