Technical and economic advantages of using elongating mandrel made of forged blank when rolling on a continuous mill with a controlled‑movable mandrel

In the article, the current problem of reducing the cost of pipe‑rolling products, which is especially acute in the world market of metal products high competition conditions is considered. A significant share in the cost of pipe products stands at the cost of rolling tools. Reducing the cost of buying a deforming tool allows you to make considerable savings in the seamless pipes’ production. The article presents: analysis of the economic efficiency of manufacturing long cylindrical mandrels from a semi‑finished product – forged billet at OJSC «BSW – management company of «BMC» holding»; development of the technological process for the production of long mandrels depending on the required size; the results on the manufacture of long cylindrical mandrels from forged billet at OJSC «BSW – management company of «BMC» holding», as well as their industrial tests in the conditions of the pipe rolling shop. A positive result of using long mandrels of the PQF mill made of forged blanks was obtained.

Evaluation of the Effect of Holding the Mandrel in the Extreme Position of the FQM Mill on the Formation of Surface Defects

Modern continuous mills FQM are high-performance technological units that allow you to get products of a wide range. The paper presents the results of the study of the effect of the time of holding the mandrel in the extreme position of the continuous mill FQM (Fine Quality Mill) on the probability of defect formation of surface defects. The problems of сcomputational simulation of the process of continuous rolling of pipes were set and solved. It is established that the increase in the holding time of the mandrel allows to reduce the sliding of the metal on the surface of the tool, and contributes to a stable process of removing the mandrel without the formation of defects on the inner surface of the draft pipe. The results of solving the problems of сcomputational modeling allowed to formulate technical recommendations aimed at reducing the probability of surface defects in the production of pipes at the FQM mill.

Effect of different foliar particle films (kaolin and zeolitite) on chemical and sensory properties of olive oil

<p>During the growing season, the use of foliar treatments based on fine grained geomaterial to reduce the negative impact of environmental stresses and protect the olives from insect pests is a well-known approach; however, while kaolin powders have been widely employed, zeolitite-based materials are much less known and exploited.</p><p>The aim of this study is to assess the effect of the two different treatments (zeolitite and kaolin) on the chemical and sensory qualities of the oils produced.</p><p>The study was carried out during two consecutive crop seasons in a 15 year old commercial olive orchard (Olea europaea), cv Correggiolo, located on the Appennine hills near Bologna (Italy). Foliar treatments were distributed during summer, until olive harvest. Ripening index, weight, oil and water content were measured on olive fruits. Olive productions were transformed in oils using a low scale continuous mill, quality parameters (free acidity, peroxide numbers, K232, K270, total phenols, fatty acids) were evaluated according to the official methods described in Regulation EC 2568/91 and subsequent amendments. Phenolic compounds, vitamins and pigments were determined by HPLC-DAD. Sensory analysis was performed by the panel of Agency for Agrofood Sector Services of Marche region (ASSAM), a fully-trained analytical taste panel recognized by the International Olive Oil Council (IOC) of Madrid, Spain, and by the Italian Ministry for Agriculture, Food, and Forestry Policy.</p><p>Olives treated with zeolite showed higher oil contents with respect to the other treatments. Oils produced by plants treated with zeolite particle film exhibited higher contents of total phenols, tyrosol, oleuropein and secoiridoids than to the oils produced by other treatments. Oils produced from olives treated with kaolin had sensory profiles characterized by sweet notes ascribable to ripe fruits, the tasters perceived notes of berries that are not typical of the Correggiolo cultivar.</p><p>The sensory taint test revealed a statistically significant difference between oils produced from olives treated with kaolin and the control, whereas no difference emerged between oils obtained from olives treated with zeolite and the control.</p><p>Particle film can influence some physiological plant parameters (photosynthesis, transpiration, water use efficiency) and, by consequence, it has also an influence on olive and oil quality. Olive plants treated with zeolite produced oils with higher antioxidant endowment, while oils produced from plants treated with kaolin were characterized by lower phenolic contents. Moreover, the kaolin treatment significantly affected the organoleptic properties of oils.</p>

Calculation of metal resistance against plastic deformation accounting its softening during continuous rolling

The value of metal resistance against plastic deformation is an important parameter at designing of technological equipment and plastic deformation modes, since it determines considerably energy and power parameters during rolling process. Usually it is represented as dependence on deformation rate, value of accumulated deformation and temperature at which the deformation takes place. Application of such dependences usually gives a satisfactory coincidence with experimental data. However, the perfection of the rolling processes results in increase requirements to the calculation accuracy of the deformation parameters, including the value of metal resistance against plastic deformation. At the production of metal products and pipes, the processes in which a metal is subjected to multiple deformation, are widely used. One of the ways to increase the calculation accuracy of the value of metal resistance against deformation is the accounting of metal softening between their stages. Calculation of variation of the metal resistance value presented, accounting and without accounting the softening during pipes rolling at a mandrel in a four-stand continuous mill. It was shown that the softening could have a significant influence on the value of metal resistance against plastic deformation. Accounting the softening and various processes taking place along both the roller pass perimeter and the mill length, gives an actual picture of stress and deformation state of metal.

The Calculating Method of Thinning Pipes Ends before Rolling in the Reduction Mill

In this article it is discussed one of the main directions of improving the rolling tubes technology on a pipe-rolling plant with a continuous mill, in order to reduce the pipe-ends cut. A method for preliminary end sections thinning modes, calculating during rolling on a continuous mill, to compensate for wall subsequent thickening in the reduction mill, has been developed. Method distinctive feature is the calculation of end thickening volume, which must be reduced by a specified quantity when end sections rolled. The sequence of technological calculations is given. The results of pipe reduction computer simulation by regular rolling modes, and modes calculated by the proposed method, are represented The analysis of the simulation results showed the possibility of thickened ends length reducing of at least 10%.

Mastering of seamless pipes production from martensiticclass stainless steel of 13Cr grade type at the JSC “VTZ” TPA 159–426 pipe mill

Mastering of offshore deposits of hydrocarbons require application of new types of pipe products, capable to effectively work under conditions of constant impact of aggressive media. In this connection new tasks arose to produce seamless hot-deformed pipes made of martensitic class stainless steels with increase chrome content. Mastering of such pipes production is connected with necessity to overcome a series of technological problems. The problems are stipulated by metal structure peculiarities, appeared in low plasticity and narrow temperature range for hot deformation, increased inclination to defects formation in the rolling process, as well as more intensive wear of rolling instrument, in particular of that of piercing mill. Main stages of seamless pipes production mastering, made of type 13Cr steel grades at TPA 159–426 line with TPZ-3 continuous mill of JSC “Volzhsky Pipe Plant” presented. The complex of measures for the noted problems overcoming, including semi-product type selection, piercing mill rolling instrument calibration change, as well as deformation regimes and other measures presented. The elaborated complex of measures allowed providing of pipes manufacturing of necessary quality for PAO “Gasprom” demand as per TU 14-3Р-129–2015 specifications.