Stainless Steel Welded Pipe Immersion Methods

Stainless steel welded pipe liquid immersion methods are the following 10 kinds:

　1, ordinary processing, general acid is enough, and then in the water cleaning.

　2, deeper: the program is a little more, acid washing, alkali washing, water washing, polishing, waxing, etc.

　3, precision: ultrasonic degreasing to oil, the surface to be sprayed, grinding, oxidation, rust treatment:

　Method 1: degreasing commonly used solvents: trichloroethylene, acetone, butanone, benzene, ethyl acetate.

　Method 2: Degrease after sandblasting or emery cloth grinding.

　Method 3: Impregnation for 10 minutes at 70-85°C in the following solution: sodium silicate 6.4 sodium pyrophosphate 3.2 sodium hydroxide 3.2 descaling powder 1 water 32 Wash with cold water and dry at 93°C.

　Method 4: After degreasing, dip for 10 min in the following solution at 80°C, pH=12.65: Sodium phosphate 8.5 Sodium pyrophosphate 4.2 Sodium hydroxide 4.2 Surfactant 1.4 Water 380 Remove and rinse, then dip for 3 min at 65°C in the following solution: Chromium oxide 20 Water 380 Rinse with water and dry.

Method 5: Dipping for 5-10 min at 65-70°C in the following solution: Hydrochloric acid (37%) 2 Hexamethylenetetetramine 5 Water 20 Then add 30% hydrogen peroxide, remove, rinse and dry at 93°C.

　Method 6: Impregnation for 10min at 50°C in the following solution: saturated solution of potassium dichromate 0.35 sulphuric acid (d=1.84 ) 10 Then brush off the charcoal residue, wash with distilled water and dry at 70°C. This method is suitable for occasions where maximum peeling strength is required.

　Method 7: In a lead-lined tank, sulfuric acid concentration of 500g/l, anodized for 90s, voltage 6V, rinsed with water, washed with distilled water, dried at 70°C, with the adhesive joints as the anode, and then passivated for 20min in 5-10% chromium oxide solution after treatment.

　Method 8: Impregnated for 10min at 85-90°C in the following solution: oxalic acid 37 sulfuric acid (d=1.84) 36 water 300 washed with distilled water and dried with warm air.

　Method 9: After degreasing, impregnate for 10 min at 65°C in the following solution: hydrochloric acid (d=1.19) 52 hydrogen peroxide (30%) 2 formaldehyde (38%) 10 water 45 After washing with water, impregnate for 10 min at 65°C in the following solution: sulphuric acid (d=1.84) 100 sodium dichromate 10 water 30 After washing with distilled water, dry at 70°C.

　Method 10: After alkaline washing with water-soluble industrial soap, washing with hot water at 40°C for 5min and drying at 120°C, the product is then impregnated for 2min at 100°C in the following solution: hydrochloric acid 200 Phosphoric acid 30 Hydrofluoric acid 10 Washing again with hot water at 40°C for 5min and drying at 40°C for 30min.