The company’s top management and sales team are well acquainted with the Russian market, its mentality and laws; they also understand industrial specifics of the financial and economic activities of the Russian customers. All our sales managers have a large customer database, extensive experience of successful sales and well-established connections with the potential buyers of your section stands. This allows our managers to promptly set out the most promising directions for promotion and to ensure a rapid entry of the products into the promising Russian market. Our employees, who are fluent in English and German, are focused on working at the international market with the supplies of foreign equipment.
Our team of experienced engineers, who can handle the most serious technical problems, constantly keeps in touch with the Russian customers, holds meetings and delivers presentations regarding the latest achievements of our manufacturing partners. They point out the engineering challenges and actively communicate with all the departments at Russian plants. That is why the specifics of doing a business in the Russian Federation are well-known to us, and we also know the equipment of the local industrial plants and their up-to-date modernization needs.
Once we become your authorized representative in Russia, our marketing staff will carry out a market research in order to check the demand for section stands, will submit a market overview for section stands that you offer and evaluate the needs for this type of equipment at local plants. Our specialists will also estimate the potential and capacity of this market at local industrial plants. Our IT-team will start developing a website for your products in Russian. Our experts will assess the conformity between your section stands and customer needs as well as analyze the common reaction to the new goods in general. We will look into the categories of potential customers, and pick out the largest and the most promising plants.
Upon becoming your authorized agent on the territory of Russia, ‘Intech GmbH’ LLC (ООО «Интех ГмбХ»), will obtain certificates, if required, for a batch of the goods, for various types of section stands in compliance with Russian standards. We can also arrange the inspection in order to obtain TR TS 010 and TR TS 012 Certificates. These certificates provides permission to operate your equipment at all industrial plants of the EAEU countries (Russia, Kazakhstan, Belarus, Armenia, Kyrgyzstan), including the hazardous industrial facilities. Our company is eager to assist in issuing Technical Passports for section stands as per Russian and other EAEU countries’ requirements.
Our engineering company ‘Intech GmbH’ LLC (ООО «Интех ГмбХ»), collaborates with several Russian design institutes in various industrial segments, which allows us to conduct preliminary design as well as subsequent design works according to the standards, construction rules and regulations that are applicable in Russia and other CIS countries. It also enables us to include your section stands into the future projects.
The Company has its own logistics department that can provide packing service, handling as well as the most efficient and cost effective mode of transportation of the goods (incl. over dimensional and overweight goods). The goods can be delivered on DAP or DDP-customer’s warehouse basis in full compliance with all the relevant regulations and requirements that are applicable on the Russian market.
Our company has its own certified specialists who will carry out installation supervision and commissioning of the delivered equipment, as well as further guarantee and post-guarantee maintenance of section stands. They will also provide necessary training and guidance for the customer’s personnel.
A rolling mill is a complex of equipment designed to perform plastic deformation of metals by rolls (i.e. for rolling) and to perform transport and auxiliary operations. Rolling workshops or divisions generally features equipment of the rolling mill main line as a part of roughing, intermediate and finishing operating stands and transfer mechanisms, as well as heat-treating furnaces, descale spray systems, equipment for handling, cutting, heat treatment, finishing, correction, coiling, marking, packing of rolled products, etc.
The main goal of rolling production is to get finished rolled products of specified dimensions and shapes in the amount required while providing for minimum possible costs, high physical and mechanical properties and surface quality.
Section rolling mills are divided into single-strand and multi-strand mills.
By the roll arrangement, stands are divided into horizontal, vertical and universal ones. Be the rolling direction, they are divided into continuous and backward ones.
Depending on the parameters of the products being manufactured, section rolling mills are divided as follows.
|Medium section mills||Circle of up to ∅75 mm;
Shaped profiles with a side of up to 90 mm
|Small section mills||Circle of up to ∅30 mm;
Shaped profiles with a side of up to 40 mm
|Wire mills||Wire rods of ∅6-10 mm|
Modern rolling production claims increased requirements to manufacturing of products with the properties required, to compactness, universality, cost efficiency, repairability, and power capacity of the equipment.
While the requirements to dimension accuracy of the rolled products and their finishing quality is increasing, special attention is also paid to production flexibility of the equipment, its fast readjustment, if needed, in order to produce different schedules, and to reduction of downtime caused by repair and maintenance of the equipment.
There is a tendency to cast billets with the shape and dimensions close to the desired parameters of the finished products, which significantly changes the rolling procedure. Namely, the number of the passes and rolling stands required is reduced, therefore, the design is simplified; and overall dimensions and specific consumption of energy carriers is decreased. Yet, a decreased drawing coefficient puts increased requirements to the structure of the finished rolled products and makes it necessary to use thermal treatment extensively.
The tendencies of the modern metal production market are manifested in a decrease of the range of dimensions of the finished rolled products and in a wider steel grade variety. In any case, in order to provide maximum performance, it is necessary to ensure the lowest duration of readjustment when changing to manufacturing of rolled products of another standard size, profile or steel grade, and to decrease downtime duration related to maintenance of the equipment
The main types of products are building bars, wire rods, wires, angles, hexagons, and etc.
Mills for cold-rolling of ferrous and non-ferrous metal strips features equipment, which is designed to roll the material in cold state using the cold deformation technique. It means that the starting metal is not preheated in a furnace prior to rolling.
This rolling technique is used to produce a thin strip or a band with the minimum thickness, with even bright surface, precise section dimensions and high homogeneity of material properties. During cold-rolling, it is possible to change mechanical properties of the metal being processed by selecting the drafting and temperature parameters required. Nowadays, cold-rolling of materials using the cold deformation technique is commonly used, as well as, cold-rolled products, which are commonly applied almost in all the fields of modern industry.
The aforesaid developments can be already partially implemented on existing and operating cold-rolling units. This will lead to performance enhancement of already operating mill units with insignificant financial costs.
The “band” term is related to the strip thickness because up to a certain point, some problems related to rolling of wide strips with a thickness of ≤0.2 mm existed. That is why the coils that had to be rolled into a strip with ≤0.2 mm thickness should have been disbanded, in other words, longitudinally separated into several strips. After that, the longitudinally cut strips were rolled on the mills with rolls of smaller diameter and with a smaller body.
Nowadays, multi-hi rolling lines exist, in which the number of rolls can be up to 20, so there is no need in longitudinal separation of the roll, as it is possible to produce thinner and wider strips using the multi-hi unit. In the near future, it might be possible to roll strips with the minimum width of 1000 mm and thickness of 0.05 mm. And only after that, the strip will be separated to be cut longitudinally into strips of the width required. However, very thin strips, special alloys and materials will be rolled on narrow-strip mills.
Due to production of very thin strips, the requirements to uniformity, i.e. regularity, of the strip thickness have become stricter. Strip profile is related to thickness variation; that means the average difference between the strip thickness in its center and thickness within a certain distance from the strip’s edge or ends.
It is suggested, that the profile of cold-rolled strips depends on flatness of starting semi-finished rolled products that are fed from the hot-rolling line. For example, the convex profile of a cold-rolled product is almost equivalent to that of the starting material that was manufactured using the hot-rolling technique.
The temperature impact on the strip, deformation speed, a stable gap in the deformation zone, and a strip’s strain parameters influence thickness variation of the metal along the whole strip length respectively. Thickness variation is affected not only by these factors but by grinding precision of the support roll body as well. The design of the support unit and configuration of the roll trunnion (cylinder or cone) define the control method preferred to determine dimension accuracy achieved during grinding.
There is also a number of other factors that affect differences of metal thickness along the whole strip length. It is clear that material thickness variations can be caused by rolling speed alteration, which is, however, virtually impossible to avoid, especially, when decelerating and accelerating the unit.
The friction coefficient created between the rolls and rolled material changes, thus causing thickness variations. Stability of the rolling mode facilitates uniformity of the strip thickness to a great extent. Coils should be fed to the mill with minimum pauses. Therefore, an almost continuous rolling process is ensured providing for the temperature mode required that affects the rolls’ profile. Big pauses between coil feeding impair the set modes, thus the demand for their correction is risen, and at the end, the parameters of the finished strip leave much to be desired. The thickness variation of cold-rolled products can be caused by a poor quality of the support rolls of the mill. It is necessary to ensure precision of grinding when grinding the roll body, thus thickness variation parameters is minimized. The thickness variation along the whole strip length can be also caused by beating of the rolls in the stand.
The thickness of the rolled material and rolling precision allow certain eccentricity of the rolls and their beating.
Unseen roll defects hidden inside can lead to thickness variations as well. Due to that, the roll can be buckled a lot under a high load. A non-destructive test instrument is used to test the rolls for internal defects using ultrasound.
Provision of sufficient rigidity in the stand also facilitates a decrease of the thickness variation of cold-rolled products. It is possible to prestress the stand by equipping it with a large number of rolls, which are made of hard materials and alloys with small diameter in order to increase rigidity.
Cold-rolling mills are equipped with thickness controllers operating in the automatic mode in order to decrease thickness variations of the rolled material; in addition, it leads to correction of the strip profile. Hydraulic screwdown devices, bend, negative bend of rolls, strip strain, roll cooling methods and rolling speed are affected as well.
These units are divided into non-reverse, or reverse, or continuous rolling units.
A single-stand mill (a mill with one stand) may be considered as a non-reverse mill. The direction of rolls rotation doesn’t change. A strip being rolled is always fed from the recoiler side and it is always transported from the decoiler at the output. This equipment is always used to roll sheet materials or coiled strips, when it is possible to perform one-pass rolling. This method is usually applied to roll aluminum foil or for rolling at a dressing mill.
A single-stand mill (a mill with one stand) may be considered as a reverse mill as well. The direction of rolls rotation doesn’t change. A strip is rolled in one direction first and then in another, in several passes, this determines final parameters of the finished rolled products.
A multi-stand mill (a mill with multiple stands) may be considered as a continuous mill. The stands in the mill are arranged one after another, rolling is preformed continuously and in all stands at the same time. Cold-rolled production may comprise 6 stands (for tin and thin strips) or up to 20 stands when rolling small-section rolled products out of special steels. The direction of rolls rotation doesn’t change. A strip being rolled is always fed from the recoiler side and it is always transported from the decoiler at the output.
Nowadays, all continuous cold-rolling mills are equipped with rolling controllers that operate in an automatic mode: they ensure continuous process without units being stopped. Next coil is charged at the input when the finished coil is removed at the output.
The input section of such mills is equipped with a decoiler line that consists of 2 decoiling devices, straightening and straining machine 2, shears 3, welding machine 4, loop accumulator 5 that are necessary for the unit when welding at a low speed, and tension S-rollers 6. Flying shears 8 and two coilers 9 are installed at the output of continuous mill 7.
When the coils achieve the set length, the flying shears operating according to the guillotine principle cut a strip, and the coil end is fed to the second recoiler. The rolling speed is 5 m/s if the flying shears are in operation.
Combined lines consisting of the pickling line and cold-rolling mill should be given special consideration nowadays.
The pickling line has the speed matching to the high speed of processing of the material at the cold-rolling line. High quality acid and emulsion vapor exhausting system operates at the pickling line and the mill, thus ensuring more careful and less destructive operation of the equipment of both lines. The strip accumulator may be vertical and due to that the combined line length may be overall decreased.
Combined lines have advantages as follows:
The requirements for the cold-rolled strip has become stricter. It is true both for the thickness precision parameters, strip flatness and strip surface cleanness. These requirements make up the base of the design versions of the equipment of the rolling stands, mill input and output and other auxiliary equipment.
Design modifications are made in rolling mill stands. Higher rolling forces are used in order to achieve prestressing in the stand, pressing devices became hydraulic, oil film bearings were enhanced more, and etc. The operating and support roll bending and anti-bending system enhances the indexes of strip flatness and increases the lifetime of the roll in between regrinding processes.
Tension meters are installed on rolling units in addition to strip flatness control means. These meters measure a strip’s strain within its width. The hydraulic screwdown system, operating and support roll bending and anti-bending system, and axial shift enhance precision of the indexes of strip or band thickness.
A rolling stand is equipped with a certain amount of rolls further determining a name of the rolling unit. Two-hi stands are suitable for rolling of section profile materials, narrow bands and strips, wire flattening, and pinch rolling procedures. The technology of these procedures requires a certain design equipment of the stand with two rolls. The load on rolls and rolling speed determine the choice of bearings to equip the stand: rolling bearings, plain bearings, roller bearings, and etc. Their design is changed continuously in order to increase service life and decrease friction heat losses.
Two-hi mills may be of non-reverse, reverse or continuous type. Continuous two-hi mills are used to roll foil and flatten wire. The equipment has a pretty simple configuration including a decoiling device; stand for material rolling, and a coiler.
Nowadays, a four-hi mill is the most widely used rolling equipment for production of cold-rolled materials. The stand of a four-hi mill comprises four rolls: two operating rolls and two support ones. The material is rolled between the operating rolls; the support rolls enhance rigidness in the stand, which is facilitated by various installation types of the operating rolls. Usually support rolls have a larger diameter than the operating ones, thus preventing deflection of the operating rolls. Only operating rolls are driven in four-hi units.
Operating rolls are placed a bit in front of support rolls so that the operating rolls are pressed against the support rolls during a non-reverse rolling mode, thus preventing operating rolls to deflect. Rolls can be located with no axial shifting, but then support rolls will be located by two sides.
Optionally and depending on the technology, either of the rolls on a four-hi unit can be controlled. It is better to make support rolls driven, not the operating ones. If the ratio between the roll’s length and diameter exceeds 5:1, then support rolls should be chosen as driven ones. These stands are used to roll thin material with a high content of C or Si, stainless steel and other materials that require application of a high rolling force. Thin materials with a high content of C or Si, stainless steel, and high alloy steels are rolled in the stands of the mill with driven support rolls, the thickness of the rolled strip can be up to 0.2 mm.
When rolling softer material using driven support rolls, a higher drafting force can be achieved.
The rolling stand housing bears the main loads occurring during rolling. Housings are made of steel casting. Foundation plates for the housings are made out of steel. Special tightening mechanisms connect housings and enhance their rigidity. Support rolls are installed in openings of the housing.
Inserts providing adjustment of the cushions of operating rolls and hydraulic screwdown devices are attached to housings. Diameter of the rolls is decreased during each grinding. That is why, at the bottom, under the cushions of support rolls, special mechanisms are installed that adjust the position of the roll towards the rolling line according to the roll’s new diameter after grinding.
Upper cushions of support rolls are equipped with rolling force meters. Hydraulic screwdown devices adjust the gap between the operating rolls in the deformation zone.
Bearings of rolling rolls can bear very high loads. They are located in big cushions installed in the opening of the housing. Oil film bearings (OFB) are installed in support roll cushions. Operating roll cushions are operated using roller bearings (cylindrical).
Bearings for support rolls are chosen depending on the load on support rolls and rolling speed. The rolling bearings, which are installed at high performance mills for coiled material rolling at a high processing speed (10-15 m/s), wear out quite fast. Thus, diameters of support rolls are increased to use standard roller bearings or oil film bearings. It is recommended to use the latter, as they have the following advantages:
In this mill, intermediate rolls are driven. The ends of the intermediate rolls are grinded conically; one roll may be grinded conically from the driver side and another one - from the operator’s side.
Intermediate rolls can be shifted along the axis towards strip edges, which facilitates strip flatness. Intermediate rolls rotate in different directions. The friction coefficient is decreased at a low rolling speed. Transverse thickness variation of the strip or band on the mill is significantly lower than that on four-hi mills.
Multi-hi rolling mills have recently become more widely used, which is caused by a change of the demand on the market of metal products. The demand for thin high-carbon band and stainless steel or special steel carbon band has increased. This demand is not easy to meet using standard mills, a lot of passes and intermediate processing procedures are required.
A band or a strip with the minimum thickness can be rolled now due to application of a big number of rolls of a small diameter.
Investment into multi-hi mills has a number of advantages:
The main advantage of multi-hi mills is production of a high quality strip or band, as there is almost no transverse thickness variation or there is a very small thickness variation on the material.
These stands can be non-reverse, as rolls continuously rotate in one direction, and reverse. Here, only two operating rolls of a small diameter are driven, all other rolls of a greater diameter are used as support rolls; they bear no load during rolling. Bands or strips rolled on such mills have quite a long length; they are coiled in bundles or coils.
Various devices are used in the stand to adjust roll profiles in order to decrease thickness tolerance and enhance surface flatness parameters, namely, by means of:
The strip edge thickness will always differ from the thickness of the strip in the center. Strict tolerances for the product thickness are easier to maintain on duo-mills or quarto-mills, where large diameter rolls are used and the equipment ensures enhanced rigidity in the stand.
Multi-hi mills are used to roll, for example, a band or a strip with the width of 1220 mm and thickness of 0.125 mm, with the thickness tolerance of ±3%. The length of the strip in the coil or the band in the bundle will be approximately 10,000 m or higher.
However, multi-hi mills, especially ones consisting of 20 rolls and more, have a number of disadvantages comparing to duo-mills and quarto-mills, where large diameter rolls are used. These disadvantages are as follows:
However, the choice of the rolling unit and its further design depends directly on the needs and demands of the market and consumers.
Upon becoming the official distributer of section stands, our company ‘Intech GmbH’ LLC (ООО «Интех ГмбХ»), carries out the following: finds the buyers of your products on the market, conducts technical and commercial negotiations with the customers regarding the supplies of your equipment, concludes contracts. Should a bidding take place, we will collect and prepare all the documents required for the participation, conclude all the necessary contracts for the supply of your equipment, as well as register the goods (section stands) and conduct customs clearance procedures. We will also register a certificate of transaction (Passport of Deal) required for all foreign trade contracts in the foreign currency control department of the authorized Russian bank so that currency transaction could be effected. If required, our company will implement an equipment spacing project in order to integrate your equipment into the existing or newly built production plant.
We are convinced that our company ‘Intech GmbH’ LLC (ООО «Интех ГмбХ»), will become your reliable, qualified and efficient partner & distributor in Russia.
We are always open for cooperation, so let’s move forward together!