China is a large country of iron and steel production and consumption.
Nanjing jinxin's products are mainly faced with large steel mills, in the steel mill steel line in a certain proportion.
The raw materials used in the workshop (continuous casting billet) are transported from the roller to the raw materials span of the steel rolling workshop. After all the mechanical, electrical equipment, hydraulic lubrication, water and other fluid systems in the whole workshop are ready for production, the tested raw materials are hoisted by the loading crane to the step feeding platform. The billet moves forward step by step, and the single billet moves to the roller table and is sent to the heating furnace. The hot billet is transported to the steel rolling workshop through the hot roller table, and hoisted with clamp to the step loading platform, and then entered the furnace roller table. The roll table has the function of measuring the length and weighing automatically. Plant raw material is given priority to with hot billet, the hot billet temperature 600 ~ 700 ℃.
The heating furnace is a step heating furnace, and the fuel is blast furnace gas. Continuous casting slab in reheating furnace heating to 950 ~ 1150 ℃, good billet heating by the cantilever roller sends out the heating furnace, by roller to 30 30 450 mm x 580 mm x 4 + 2 roughing rolling (cut in front of the 1 # mill set a card is broken, when failure used in roughing accident card), unit of eliminating unqualified at the billet have removed. The roughing mill is composed of six horizontal and vertical alternating mills. The rolled parts of the roughing mill enter into the medium mill unit of about 450mm x 6 after passing through the 1# flying shear head.
After the rolled parts of the outgoing mill are sent to the finishing mill through water cooling before being sent to the finishing mill, the no.2 flying shear head is sent to the finishing mill group for rolling. The finishing mill group is composed of 6 horizontal and vertical alternating short stress line mills. Single line, no twist and no tension rolling is carried out for round steel and large size screw steel (> ~ 20mm). When rolling small size screw steel (less than 30 18mm), the rack of no.14, no.16 and no.18 of finishing mill group is changed from the arrangement of vertical roll to that of flat roll, so as to realize the shearing rolling.
Starting from the no.13 rolling mill of finishing mill group, each stand rolling mill is equipped with pneumatic vertical sliding sleeve device (5) in front of each stand rolling mill, which is used to balance the pile steel caused by dynamic rapid drop of main motor when the rolling mill is biting steel, so as to control the rolling speed and realize tension-free rolling so as to guarantee the dimensional accuracy of the product.
After passing through the water cooling, the rolled parts from finishing mill group are sent to the cold table by the cold table input roller. At this time, the rolling piece is decelerated through the brake apron and sent to the cold bed. By stepping through the action of pushing steel, the rolled parts are transferred laterally and cooled naturally at the same time. Then, the rolled parts are aligned on the even-head roller table and the transfer device sends a certain number of rolled parts to the output roller table of the cold bed, and then to the 850t cold shears, which are cut into a standard scale according to the requirements of the user. The finished ruler shall be sent from the roller track to the chain collection platform, and after transference, inspection, sorting, counting and collection, it shall be automatically baled by the baler. It is then sent to the collection table via the roller track, and collected by the large bales of the collection table, for weighing and hanging of signs, and finally transported by the electromagnetic crane to the finished product warehouse.