Before the pickling process, it is advisable to preheat the steel pipe blanks in hot water at a temperature of 25-50°C for 1-3 minutes before proceeding with pickling. This serves several purposes:
(1) It removes iron filings, various dirt, and slight oil stains adhering to the steel pipe blanks that have not undergone alkaline cleaning, and it also enhances the neutralizing effect for steel pipe blanks that have undergone alkaline cleaning.
(2) Preheating the steel pipe blanks accelerates the pickling process.
(3) It reduces the consumption of directly heating the pickling solution, thereby extending the dilution effect of the acid solution.
(4) The acid solution remains cleaner, resulting in better pickling quality.
(5) It saves approximately 2 to 3% of acid consumption.
