一 ： 10%-15% lower production costs
Compared with semi-continuous process arrangement, rolled steel fully continuous arrangement reduced production costs per ton of 10-15%, mainly by increasing production, reduce fuel consumption, lower rolling power consumption and lower bearings consumption and improve the finished product rate and other aspects of implementation.
For carbon steel manufacturers, the cost of production per ton decreases to between 70-90 RMB.
二： yield increase 20%-30%
It solves the problems of long reversal rolling and big temperature droop in the semi-continuous process. The overall rolling time for rough rolling is 45-60 seconds (with threading), the rough rolling has more output capacity than finish rolling.
The annual output increased by about 20-30% compared with the semi-continuous process, and for the 650-750mm-wide strip rolling line, the output has exceeded 150,000 tons per month, The maximum monthly output is 160,000 tons，the maximum daily production is over 6,000 tons.
三：The product quality has been greatly improved
Roughing train has a fully hydraulic roll mill, precise control of the width and thickness of the intermediate slab, with small thickness difference.
Reducing the temperature difference between the head and tail and optimal intermediate blank plate so that the thickness of the finishing train AGC automatic control is more accurate, and greatly enhance the quality of the finished plate.
四：Coil weight increased by 50%
Semi-continuous rolling has a big temperature drop due to large temperature difference between head and tail along the long billets. Fully continuous rolling one solution to this problem, so that the finished roll great big increase. Increase the billet from its original six meters to 10-12 meters（the billet thick is 150-165mm).
五：The first global innovative cooling process combining the vertical coiler with super-fast cooling device to greatly improve the product quality
It is common practice for strip production lines to combine horizontal coilers with laminar cooling devices as its cooling method. However, for horizontal coilers, it is plagued with high accident rates when coiling thinner products. On the contrary, vertical coiler has its advantages when ultra-thin materials are rolled and of improving the production capacity. But scales on the product transportation chain used together with the vertical coiler is the main shortcoming influencing the final product’s quality. The first innovative design by ZZ that adopts the super-fast water-cooling process at the two-route area has remarkably improved the final products’ quality by the vertical coiler and has been rapidly promoted in the market.
六：Secondary iron oxide and surface quality comparison
•The fully continuous rolling is about 45-60 seconds, while the time for semi-continuous rolling is about 90-120 seconds.
•Semi-continuous reversible rolling process produces more secondary iron oxide, which are rolled directly into the strip surface, affecting the quality of the strip surface.
•The fully continuous rolling process produce less iron oxide, thus very good surface quality.
七：Rolling temperature contrast
•For fully continuous rolling , each pass coordinates closely ,so the temperature drop is small.
•For fully continuous rolling ,soaking hood is adopted after the roughing mills, so that the temperature difference for the intermediate billet on its head and tail is small, about 40 degree only.
•For reversible mills, simple form of soaking hood is not recommended, hot recoiling box is preferable, but it requires big investment.
八：Fuel consumption and scale loss comparison
•Semi-continuous rolling process has a leaving temperature (from the RF) of about 1250 ℃, based on actual data we have collected from over 10 production lines, the leaving temperature can be directly dropped to 1100 ℃ -1150 ℃.
•So that the fuel consumption is reduced by about 20-30%, the blast furnace gas consumption for semi-continuous rolling is 340-350m^3 / t, while that for the fully continuous rolling is 230-260m^3 / t.
•The heating time is also greatly reduced, directly reducing iron oxide loss by 0.2%
The shortening heating time can greatly increase the productivity of the RF.
九：Less varieties of billets are required
Roughing mill train is used, with broadened pass on the roughing mill, or the vertical rolls may also be used to narrow billets, so that one kind of billet may correspond to a variety of specifications, we can increase the maximum width about 100mm, so we can reduce the billet specifications, reducing the number of continuous casting mold as well the yield loss caused by changing the molds. There are 3-5 vertical rolling mills are set up on the whole line, and the width can be automatically controlled at + 30mm.
十：Water spray dedusting
•It is easy to set water spray dedusting device between the stands for the fully continuous rolling process, so that the rolling plant condition is good.
•For the reversible mills, dedusting measures are not easy to implement, so the operating conditions are hard.
十一：Relatively the same investment
Compared with the big motors and large mills used in semi-continuous rolling, the non-reversible rolling process with small motors will reduce the investment on motors as well as on electrical control systems. So the overall investment is similar to that of the semi-continuous rolling production line.
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