1、 物理脱脂剂:铝板表面有明显油渍、污垢,可用棉纱擦拭。
2、 化学脱脂剂:用专用吊车和吊具将铝板吊入煤油清洗池,清洗液比例为10%在60℃下浸泡7~10次,可使油完全溶解直至清洁。
煤油清洗池出来后,铝板吊入清洗池清洗。当铝板长时间吊离清洗池时,用一定压力的水柱对铝板两侧进行清洗。
在加工过程中,应尽量避免上道工序产生的残余清洗液进入铝板表面。清洁检查员应严格检查清洁质量和腐蚀情况。检查方法:用干净、干燥的白色滤纸擦拭铝板表面,纸面无油污,符合要求。
1. Physical degreasing agent: there are obvious oil stains and dirt on the surface of aluminum plate, which can be wiped with cotton yarn.
2. Chemical degreasing agent: lift the aluminum plate into kerosene cleaning pool with special crane and
spreader, and the proportion of cleaning solution is 10%
Use kerosene, the number of kerosene layers is at least 100 mm, the rest is 1 ~ 3% of No. 2 emulsified oil, and the temperature is 40 ℃ ~ 40 ℃.
Soaking at 60 ℃ for 7-10 times can
completely dissolve the oil until it is clean.
After the kerosene cleaning pool comes out, the aluminum plate is hoisted into the cleaning pool for cleaning. When the aluminum plate is lifted away from the cleaning pool for a long time, a certain
pressure water column is used to clean both sides of the aluminum plate.
3. Remove oxide film: use special crane and lifting tools to lift the aluminum plate into the de oxide film tank for cleaning. When preparing the solution, inject a certain
amount of water into the tank and add chemicals. After mixing, heat and stir with steam to make the solution uniform. Then you can use it. Detect the content of sulfuric acid every week and add it in time. When the effect is slow, add sodium fluoride.
See corrosion amount of sodium fluoride sulfate.
The aluminum plate is hoisted into the cleaning tank again for cleaning. The aluminum plate is removed from the cleaning tank for a long time. At the same time, clean both sides of the aluminum
plate with a certain pressure of water column.
4. Alkali washing: the aluminum plate is hoisted into the alkali tank with special crane and spreader, and soaked with 7-10% sodium hydroxide and 40-60 ℃ solution. The alkali concentration shall
be tested once a day and shall not exceed the specified value. Different thickness of aluminum plate cleaning time is different, need to pay attention to.
After the aluminum plate comes out of the alkali tank, it is lifted into the cold water
clean water tank for cleaning, and the cleaning time is 2 minutes. When the aluminum plate is lifted out of the clear water tank, flush both sides of the aluminum plate with a certain pressure water column.
5. Pickling: the aluminum plate is
hoisted into the acid pool with special spreader, cleaned with 15-30% dilute nitric acid solution at room temperature for 1-3 minutes, and treated to neutral. Detect the acid concentration once a week and add it in time.
Lift the aluminum plate
into the 50 ℃ ~ 60 ℃ hot water clean water tank for 2 ~ 3 minutes. When the aluminum plate is scattered outside the clean water pool, use a certain pressure water column to wash both sides of the aluminum plate at the same time.
6. After cleaning,
put the aluminum plate into 100 ℃ ~ 150 ℃ oven in time to dry for 30 minutes, or air dry.
In the process of processing, the residual cleaning solution produced in the previous process should be avoided as far as possible. The cleaning inspector
shall strictly check the cleaning quality and corrosion. Inspection method: clean and dry white filter paper is used to wipe the surface of aluminum plate, and the paper surface is free of oil stain, which meets the requirements.