The aluminum and aluminum alloy flat ingot, continuous casting or continuous casting and rolling strip are used as raw materials, and the aluminum processing plant workshop design for aluminum sheet and strip is produced through rolling, heat treatment and finishing.

Aluminum sheet is divided into hot rolled sheet and cold rolled sheet. The general specification range is: hot rolled sheet thickness 5～150mm, width 1000～2500mm, length 2000～10000mm; cold rolled sheet thickness 0.3～10mm, width 400～2400mm, length 1000 ~ 10000mm. The strip has a thickness of 0.2 to 4 mm and a width of 50 to 2,500 mm. The product is supplied to the user in the state of hot rolling, annealing, quenching-aging, and cold work hardening. The strip with a thickness of about 0.5 mm is also used as a blank for the aluminum foil workshop.

The main contents of the design are: process selection, equipment selection and workshop layout.

Process selection

Aluminum and aluminum alloy sheet production, using hot-rolled billet or cast-rolled billet, followed by cold rolling, heat treatment, finishing and other processes. Hot-rolled billet is suitable for the production of various aluminum alloys. The quality of the strip is good, but the production process is numerous, the equipment is complicated, and the investment is large. It is suitable for use in the strip and strip workshop of scale above 100,000 t/a. The method of casting and rolling is short, the production process is short, the energy consumption is low, and the investment is saved. However, the alloy varieties have certain limitations, and are suitable for a single strip and strip workshop. The casting and rolling feeding method is simple and suitable for use in workshops with a production scale of less than 50,000 t/a. In addition, another method of producing aluminum sheets is a block production method in which a slab is hot rolled into a strand and then cut into pieces for cold rolling, heat treatment and finishing to a finished product. This method has low production efficiency and yield, and is only suitable for sheet metal workshops with an annual output of several thousand tons.

Device Selection

Including heating furnaces, hot rolling mills, cold rolling mills, heat treatment equipment and finishing equipment.

Heating furnace

Continuous heating furnaces and chamber heating furnaces are usually used. (1) Continuous heating furnace. According to the feeding method, it is divided into two types: push type and chain type. The pusher type furnace is to stand the ingot side on the material pad, and the furnace uses a fan to force the hot air to heat the ingot; it can be heated by electric resistance or heated by fuel or gas; the furnace is equipped with an automatic returning mechanism of the material pad, and the material is convenient to be loaded and discharged. The furnace type has the characteristics of high heating speed, uniform temperature, and no scratching of the surface of the ingot, and is suitable for heating large and medium slabs. The chain heating furnace is generally heated by electric resistance radiation, and does not have a hot air circulation in the furnace, and is suitable for heating with an ingot coated aluminum ingot. (2) Chamber heating furnace. There are two types of ground and underground, which can be heated by flame. There is a hot air circulation system in the furnace, which is mostly used in small strip belt workshops.

Hot rolling mill

Mainly used in single or multi-stand four-roll mills. When the annual output is below 100,000 t, a single-stand four-roll reversing mill with one-side or double-side winding is generally used; when the annual output is 100,000 to 200,000 tons, the single-stand four-roller with double-side winding is used. Reversible rolling mill or a hot rough rolling-finishing mill consisting of a four-roll reversing hot roughing mill and a four-roll reversing hot finishing mill with front and rear coiling; when the annual output exceeds 200,000 tons, the choice is from 1 to 3 A four-roll reversible hot roughing mill and a semi-continuous hot rolling mill consisting of 3 to 5 series four-roller irreversible hot finishing mills.

When a hot-rolled sheet or slab of pure aluminum and soft aluminum alloy is produced by the block method, a two-roller irreversible hot rolling mill is generally used.

Cold rolling mill

Commonly used are single-stand two-roller, four-roller, six-roll mills and a cold tandem mill consisting of three to five four-roll stands. The cold tandem mill is suitable for mass production with an annual output of over 150,000 tons. The six-roller irreversible cold rolling mill is a high-precision cold rolling mill promoted in the 1980s. The four-roll mill is also reversible and irreversible. The four-roller irreversible cold rolling mill is suitable for large-volume, high-speed, batch production methods, and gradually replaces the four-roll reversible cold rolling mill. The two-roller irreversible cold rolling mill is mostly used for the production of aluminum alloy sheets by the block method.

Heat treatment equipment

Including annealing furnace, quenching furnace, aging furnace and its supporting equipment.

(1) Annealing furnace. For intermediate annealing and finished annealing of aluminum alloy sheets, electric heating furnaces are generally used. The main furnace types are vertical annealing furnace, box annealing furnace and air cushion type annealing furnace. Vertical annealing furnace with coil turning device, mostly used for intermediate annealing of coils; box annealing furnace, there are two kinds of aluminum alloy sheets, which are made of tantalum and coiled materials, respectively, suitable for aluminum alloy sheets and coils. Intermediate annealing and finished annealing; air-cushion annealing furnace, continuous annealing after coil unwinding, good annealing quality, but large investment, only used for aluminum alloy sheets with strict quality requirements, such as aluminum strips for cans and pre-printing Finishing annealing of a photosensitive plate or the like.

(2) Quenching furnace. Used for solution treatment of aluminum alloy sheets. There are two main furnace types, air-cushion type quenching furnace, which is used for continuous quenching of aluminum alloy plates. It usually forms a unit together with the tensile bending straightening machine. The product quality is high and the production is safe, but the equipment investment is large, and it is only suitable for mass production. Aluminum plate belt workshop for high quality products; salt bath quenching furnace for quenching of aluminum alloy plates, usually combined with stretching straightening machine, shearing machine, etc., furnace temperature control is accurate, investment is less, but production efficiency Lower. Due to the corrosion and explosion hazard of the salt bath at high temperatures, the design must be fire and corrosion resistant.

(3) Aging furnace. It is mainly used for the hardening treatment of alloy aluminum plates. It can be used in box or pit type electric furnaces, and hot air circulation is required in the furnace.

Finishing equipment

For ordinary hot-rolled aluminum alloy sheets, equipment such as shearing machines, trimming machines and boring machines are often provided at the tail of the hot rolling mill column or on the side parallel to the roller table. Extra-thick hot-rolled sheets, broken panels, ribbed plates, etc. for special purposes, after re-machining on special equipment such as tension straightening machine, variable section rolling mill, variable section straightening machine, milling machine, etc. Shearing on a sawing machine or a shearing machine, heat treatment in a special quenching furnace and aging furnace, and designing a thick plate production line. The finishing equipment for the cold-rolled strip includes a continuous stretch bending straightener, a cross-cutting unit and a slitting unit. Among them, the straightening and straightening machine is used for straightening aluminum sheets and strips with high surface straightness requirements. The cross-cutting unit is used to cut the coil into sheets. The slitting unit is used to cut the coil into strips of various widths. Smaller horizontal combined shear units are available for smaller workshops.

Workshop layout

There are three main types: long strip, multi-span parallel and vertical span.

(1) Long strip layout. Consisting of a single span or with an auxiliary span, the equipment is arranged in a process sequence and is only suitable for small workshops with a single product.

(2) Multi-span parallel arrangement. Generally suitable for medium-sized workshops. The main span is the rolling mill span, the heating furnace, the transmission and electric control equipment of the rolling mill, the roll grinder, etc. are arranged on the adjacent side, and the heat treatment and finishing equipment are arranged on the other side. The workshop can be a span or multiple spans.

(3) Vertical straddle arrangement. Suitable for large workshops and medium-sized workshops with a wide range of products. The rolling line is arranged vertically with the finishing and deep processing product production line, and the heat treatment equipment is parallel or perpendicular to the rolling line according to the specific conditions of the workshop; the finishing and deep processing production lines are respectively arranged in several parallel spans. This arrangement has the advantages of short running distance in the production process, less mutual interference in production, and easy expansion and transformation.

Roll grinders are typically placed in separate rooms that are separate from the mill, and in poorer areas, closed plants are used.