FOERFARANDE FOER FRAMSTAELLNING AV OLEGERAT OCH LAEGLEGERAT STOLMATERIAL AVSETT FOER VARMFOERZINKNING

摘要

Non-alloy and low-alloy steel endure a deterioration of hot galvanization properties at a silicone level as low as 0.05 weight percent. To counteract this deterioration, the oxide film on the steel's surface at the final warm rolling stages is allowed to remain and cooling in a temperature range from 675-800 degrees Celsius is delayed for a certain time depending on the temperature, at the same time as oxygen from the outer air is kept from contacting the surface of the steel.