Brief introduction of semi-continuous pickling operation for packing steel strip

Brief introduction of semi-continuous pickling operation for packing steel strip
　　 This method uses a semi-continuous pickling unit, also called a push (or push-pull) pickling unit for pickling. Its technological operation process is: after the strip coil is uncoiled by the decoiler, it then enters the straightening machine to straighten the strip to ensure that the strip passes through the unit smoothly, and the straightened strip is removed by the acid in the pickling tank. Remove the oxide scale on the surface, and then enter the cleaning tank to remove the residual acid brought out by the strip steel from the acid tank. Then the surface is dried by the hot air drying device, and finally the edges are trimmed, the head and tail are cut off, and the strip is coiled. The machine is rolled into strip coils. Figure 3-3 is a schematic diagram of a semi-continuous pickling unit.
　　 Generally, the head of the semi-continuous pickling line does not have a guillotine shearing machine. This is because the front 'tongue' of the hot-rolled strip can pass through the line smoothly. However, a transmission pull roller is installed in each acid tank and between the acid tank, and the roll gap of the pull roll is adjustable, so that the strip end can be introduced into the pull roll more accurately. If the semi-continuous pickling unit picks two or more strips at the same time, there will also be a strip guide groove in the acid tank to ensure that several strips can run normally in parallel in the acid tank.
　　The semi-continuous pickling unit has no head shears, descaling machines (or stretch-straightening machines), welding machines, loopers (or looper pits) and other equipment, as well as conveying rollers and pulling materials The number of rollers is also much less than that of the continuous pickling unit, and the mechanical equipment of the unit is compressed to a minimum, so its cost is relatively cheap.
　　 Compared with the continuous pickling line, the simplification of the semi-continuous pickling line greatly shortens the length of the line, reduces the floor space, improves the productivity of the line, and simplifies the operation. At the same time, the variety of strip steel produced Also more. The main disadvantage of the semi-continuous pickling unit is that it cannot be combined. Therefore, this type of unit is not recommended for cold rolling mills and galvanizing plants that use large and heavy coils. When the production capacity of the cold rolling mill is not large or medium, a semi-continuous pickling unit can be used.