Sergei Nosov
Executive director, EvrazHolding

Sergei Nosov, Executive director, EvrazHolding

T

he reliability of buildings and structures depends on the quality of load-bearing construction components made of special elements. Their largest producer in Russia is the Nizhny Tagil Iron & Steel Works (NTMK), which provides the building industry with angles, channels, beams and tongues.
The range of NTMK’s rolled stock is very wide both by types of products and profile sizes. There are hundreds of items and almost each of them has its specific modifications. For example, angles are made equal and unequal. Flange beams are produced with parallel edges of flanges as well as with raked inner edges. Besides, flange beams are subdivided into the narrow-flange, medium-flange, regular-flange, brood-flange and column-flange. They all have different sizes and are made of different steels.
NTMK is the only producer of rolled products, such as flange beams with parallel edges of flanges ranging from N.20 to No.100, channels 20 and 30U, equal angles of 160 mm by 160 mm and 180 mm by 180 mm, L5-U tongues.
The term "rolled products for construction" is somewhat conditional though. For example, although they are originally designed for railroad cars, car posts and the so-called Z-sections are often used in building.
Nizhny Tagil Iron & Steel Works manufactures over the half of all Russian flange beams with parallel edges of flanges. This product accounts for about 75% of NTMK’s supplies to the building industry. It is made in the shop of brood flange beam rolling. It is the only shop in the CIS that is capable of rolling regular and brood flange beams 180 mm to 1000 mm high with the width of flanges from 90 mm to 320 mm as well as column sections 200 mm to 430 mm high with the width of flanges from 200 mm to 400 mm. The shop has the unique equipment with a high degree of automation: rolling is done in the semi-continuous mode. The technological chain contains heating furnaces with walking beam, break-down stand 1300, three groups of multipurpose stands, hot saws with laser displays of roll path and its automatic cutting as well as rolling machines, which make it possible to correct flange beams both vertically and horizontally.
The starting material for rolling at the universal beam mill is a continuously cast billet of carbon, low-alloyed and alloyed steels. The available production technology permits controlled rolling and provide flange beams with the strength of class 390.
Products are manufactured strictly in accordance with Russian standards. At the same time making flange beams has been also mastered according to the U.S. standard (W and HP types) of ASTM A6. These flange beams are used as components of beams, columns, load-bearing piles, etc. They are also made of JIS G 3101 steel by Japan’s standards JIS G 3192 as well as by the British standard BS4.
The shop also manufactures the Larsen JI5-Y tongues. These steel tongues have turned-in edges that make "a lock". This "lock" has a very important function: while anchoring soil each channel is hammered in the ground so that a "lock" of one component gets inserted into the "lock" of the other. As a result, a wall becomes very strong being able to withstand the thrust of sea waves and river waters for many years. The Larsen channel is mainly used in constructing port and shelf structures, strengthening bank slopes as well as in constructing subway and bridges. The Larsen JI5-Y was designed at NTMK in cooperation with the Scientific Research Institute of Transport Construction. It should be particularly noted that by using the channel at the depth of up to 12 m there is no need to additionally strengthen walls and this will significantly reduce labor-intensiveness of construction works.
Manufacturing new kinds of construction products has been developed lately. Among them are the channel 30Y, new sections 31B1V, 31B3V, 25D1V, 25D2V, 25D3V under the U.K. standard (BS) and two sections 35III2C and 45IIIC by the Japanese standard (JIS G 3192). At present, the work is underway to master production of channel 24.
In 2002 consumers received 700,000 tons of rolled products for construction or 8 % more than in 2001. This current winter was good: the usual seasonal downturn did not happen this time. In our view, the reason was due to decreased prices in shipments from foreign markets of products by Ukrainian manufacturers to Russia. And Russian suppliers, including NTMK, were able to sell their rolled stock to the building industry without problem.
There are hundreds of steel grades, which are melted at the enterprise. In order to make construction sections carbon and low-alloyed steels are traditionally used. Efforts to master new grades of steel, including those of higher strength, are being made so as to develop production of sections in accordance with foreign standards: the US standards ASTM A 36, ASTM A 572, ASTM A 992 and OSA-G40.21; Japan’s standard JIS G 3101. So, consumers can order products of required parameters depending on what they are going to build: industrial buildings or residential apartment houses, bridges, overpasses, etc.
The high quality is maintained at all stages of the technological process starting with reprocessing raw materials. It should be taken into account that vanadium-containing, titanomagnetite ores from the Kachkanarskoye deposit are used for smelting iron. By applying in the converter production the effective technology of reprocessing vanadium cast iron through the ‘duplex process’ with no scrap metal (that prevents foreign substances contained in scrap from getting into steel) steel makers from Nizhny Tagil obtain the so-called "first-born steel" naturally alloyed with vanadium, which significantly raises operating properties of rolled stock.
In order to manufacture construction-designed products continuously cast billets are used, which have no surface blemishes. Heating walking-beam furnaces with a high automation of the heating process secure an even warming of billets that rules out rolling defects at this stage as well.
As a rule, the rolling process and draughting schedules are automatically controlled. The controlled rolling with the use of forced cooling of rolls provides mechanical properties of the necessary degree.
The quality control system designed at NTMK regulates organization of production in all its aspects. The TUV certificate proves the compliance of this system with requirements of the ISO-9002 international standard.
The out-of-furnace treatment (RH-vacuumator, stove-bucket) is applied when making steel for construction sections. It provides accuracy and stability of the chemical composition, uniformity of the structure and low content of such detrimental substances as sulfur and phosphorus. In 2003 the converter production will be provided with a desulfurization machine having the capacity of 1.5 million tons of steel a year. It will permit to obtain metal with the sulfur content of no more than 0,001 %.
Rolled products of NTMK are in demand not only in Russia and CIS countries. They are also exported to the U.K., Egypt, Iran, Canada, China and Taiwan. The technical and technological potential of the integrated mill makes it possible to fulfill all incoming orders. So as to maintain a steady operation of doing this there is a production planning system at the enterprise, which ensures a balanced work at all stages, from preparing production facilities to the very moment of shipping products.
Despite the growing competition in this sector of the market, Nizhny Tagil Iron & Steel Works intends to maintain existing volumes of supplies to traditional customers, including those beyond CIS countries.