Name: Anshan Iron and steel machinery development private enterprise machinery plant
Contact: Shen Taisheng
Mobile phone: 13942222400
Zip code: 114000
Site: Anshan Iron and steel plant
Office address: Xi min, Tiexi District, Anshan, Liaoning
No. 111 Sheng Lu
When replacing the zinc pot or stopping the galvanizing furnace because of the need of testing and repairing the zinc pot, the zinc liquid must be extracted from the zinc pot. Stopping the operation of the zinc pot at one time will cause considerable losses, which will increase the additional cost and may cause accidental damage to the pot. To avoid accidents, the entire process from shutting down to reheating and resuming operation needs to be well managed.
1. extraction of zinc
Zinc pots need to be extracted from the zinc pot after stopping operation. Zinc liquid can be pumped into the spare large zinc ingot mold to form large zinc ingot, which can not only reduce the oxidation of zinc, but also easier to stack and transport. However, the weight of large zinc ingots should not exceed the lifting capacity of the hot dip galvanizing workshop. Before extracting zinc liquid, the following work must be done well: equipped with enough zinc ingot mold and suitable placement and demoulding position; trial run zinc pump; before extracting zinc, the zinc liquid is cooled to 440 C or even lower, careful operation to remove zinc slag; after removing slag, the zinc liquid is re-heated to 465 470 C, and then can start shooting zinc. After the zinc liquid in the zinc pot is finished, the zinc pot can be cooled naturally or forced to cool with the fan.
2. detection of zinc pot
When testing the zinc pot, the inner wall of the pot is inspected visually to check the deformation, erosion pit or wave damage of the pot. Then the thickness of the pot wall was measured by ultrasonic thickness gauge to determine the thinning of the pot wall and the severity of local erosion.
Ultrasound testing, it is best to wait for the zinc pot cooling to room temperature; the iron-zinc alloy layer on the pot wall must be removed, so that the pot wall copper substrate exposed. Although the thickness of the wall of a zinc pot can also be measured outside the pot by an ultrasonic thickness gauge when the pot is filled with zinc liquid, it is difficult to test the thickness of the pot at all measuring points, so the whole situation of the pot can not be determined. It is an effective method to probe the inner wall of the pot by experienced personnel with steel hooks. In addition to inspecting the zinc pot, the entire combustion system (fuel, gas, electricity, control and other equipment) must be inspected and repaired at the same time.
3. repair of zinc pot
The zinc pot is severely eroded, or the four pit must be repaired by welding. Welding and repairing the zinc pot should be done by skilled welders or zinc pot manufacturers. Before filling and welding, the zinc and iron-zinc alloy coatings attached to the surface of the pot wall must be removed, and the clean surface exposed to steel must be ground and cleaned. The filler material should be the same as the zinc pot material. After welding, the welding area and the surrounding area must be polished to be as smooth as other parts of the pan wall.
4. zinc pot reused
In principle, the steps and operation methods of the zinc pot which has been inspected and repaired, or the old one which has been put into use for a period of time, are exactly the same as those of the new one. Old zinc pots must be cleaned before heating.
A large heated and insulated container has been introduced abroad, which can store zinc liquid when inspecting or replacing zinc pot. Each container can hold dozens of tons of zinc liquid, and is equipped with zinc pump and pipeline. The equipment can be transported on a common trailer and can serve the hot dip galvanizing enterprises conveniently. This not only saves time, saves the trouble of casting zinc ingot and loading zinc ingot into zinc pot, but also significantly reduces the loss of zinc oxidation and energy consumption of heating molten zinc, and reduces the cost. Of course, this kind of container can also be combined with zinc ingot mold to use, check or replace the zinc pot after completion, the zinc ingot into the bottom of the zinc pot, and then the zinc in the container into the zinc pot, but at this time must be carefully operated to avoid the flow of zinc directly impact on the wall and bottom of the pot.