Crystallizing Metal Shrinkage: Automation of High-Pressure Crystallization Control

The properties of bulk metal products are formed when molten metal transforms from an unstructured liquid into a solid crystal state. We suggest a new approach to the automation of the control over crystallized metal shrinkage compensation based on controlling the law of change in pressure applied to crystallizing metal through a program taking into account the transition process in the hydraulic system of the production equipment. We observed the increase in rigidity, durability, and pliability of В95-alloy samples as compared to cast aluminum alloys. The metal utilization rate can be increased up to 0.90 of the liquid metal volume.

Some Evaluations on the Technical State of Metal Products and Determination of their Safe Operation Period on the Basis of Criterial Control

Over a long period of operation, under the influence of corrosion and stresses from the acting forces, metal structures lose their strength. There is a need for their periodic non-destructive testing. The development of new methods is relevant in the field of control of building metal structures, such as bridge structures, structures of building cranes and other mechanical engineering products. The applied methods should be reliable and should not require huge material and labor costs. In this work, informational relationships between acoustic characteristics and parameters of metal microstructure are established. The proposed method can be useful for specialists and experts in the field of monitoring the technical condition of metal products requiring non-destructive testing. The safety of the operated objects depends on the accuracy of the applied criteria, as well as the degree of resource saving due to the full use of the product resource.

ДОЦІЛЬНІСТЬ ЗАСТОСУВАННЯ СТЕРИЧНО УСКЛАДНЕНИХ АЦЕНАФТЕНОВИХ СПОЛУК У СКЛАДІ ПРОТИКОРОЗІЙНОЇ КОМПОЗИЦІЇ

Goal. Synthesis and study of the effect of the inhibitory component – sterically complicated acenaphthene compounds – on the effectiveness of the protective composition to prevent corrosion of metal products during the period of temporary preservation.Method. Coke-chemical acenaphthylene was isolated from the absorbing and anthracene fractions of coal tar, the bromination of which led to 1,2-dibromocenaphthene. Subsequent alkylation of azine bases with 1,2-dibromacenaphthene yielded a number of sterically complex acenaphthene compounds. In the conditions of simulation aggressiveness of NSS environment the influence of synthesized additives on efficiency of anticorrosive composition is investigated (ISO 9227:2017). Research methods: chromatography, synthesis, elemental analysis, IR spectroscopy, corrosion tests.Results. On the basis of low-demand, available and inexpensive components of coke production, a number of substances with high anti-corrosion properties were synthesized – Quaternary azine salts with acenaphthene fragment. It was determined that the greatest resistance to the destructive effects of corrosive NSS environment according to the results of accelerated atmospheric corrosion tests was demonstrated by a composite coating containing an inhibitory additive – 1-(2-bromo-1,2-dihydroacenaphthylen-1-yl) quinoline bromide. The dominant role of the structure of the inhibitory additive on the manifestation of anticorrosive properties of the protective composition is shown. The influence of the ratio of components of paints and varnishes on their technological and anti-corrosion properties has been studied. The obtained results allow to create a new formulation of the domestic competitive protective composition to prevent corrosion of the metal for the period of temporary preservation.Scientific novelty. The role of 1,2-dibromacenaphthene as a promising alkylating agent in the synthesis of inhibitory additives - sterically complicated acenaphthene compounds has been determined.Practical significance. The optimal content of inhibitory components – Quaternary azine salts with acenaphthene fragment – for the development of a formulation of an effective anti-corrosion composition for the period of temporary preservation of metal products.

A Sustainable Process to Produce Manganese and Its Alloys through Hydrogen and Aluminothermic Reduction

Hydrogen and aluminum were used to produce manganese, aluminum–manganese (AlMn) and ferromanganese (FeMn) alloys through experimental work, and mass and energy balances. Oxide pellets were made from Mn oxide and CaO powder, followed by pre-reduction by hydrogen. The reduced MnO pellets were then smelted and reduced at elevated temperatures through CaO flux and Al reductant addition, yielding metallic Mn. Changing the amount of the added Al for the aluminothermic reduction, with or without iron addition led to the production of Mn metal, AlMn alloy and FeMn alloy. Mass and energy balances were carried out for three scenarios to produce these metal products with feasible material flows. An integrated process with three main steps is introduced; a pre-reduction unit to pre-reduce Mn ore, a smelting-aluminothermic reduction unit to produce metals from the pre-reduced ore, and a gas treatment unit to do heat recovery and hydrogen looping from the pre-reduction process gas. It is shown that the process is sustainable regarding the valorization of industrial waste and the energy consumptions for Mn and its alloys production via this process are lower than current commercial processes. Ferromanganese production by this process will prevent the emission of about 1.5 t CO2/t metal.

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.

Monitoring the structural condition of parts of K 250 centrifugal compressors at different stages of production

Among the existing methods of ensuring the production of goods, an important place is occupied by the input and final quality control of metal products in production. The main task of the input control is to constantly ensure the necessary level of quality, fixed in regulatory documents, by directly checking each batch of supplied metal. The use of active quality control directly during the production of goods allows to prevent and detect defects at the initial stages and during the manufacture of finished types of metal products. Control at the output of the production system has the main purpose to prevent the transfer of defective products to the consumer or to the subsequent technological phases (stages). Goal. The goals is development of methods for monitoring the parts of K-250 centrifugal compressors at various stages of production and selection of the optimal mode of heat treatment of rotor elements made of structural steel of the martensitic class of the 34KHN1MA brand. Method. The control included mechanical tests, metallographic studies of blanks and finished parts, as well as non-destructive testing for internal defects and surface quality. Results. A comprehensive input control of the macro- and microstructure, as well as the mechanical properties of blanks made of 34KHN1MA steel was carried out. A mode of improving the properties of critical parts of a centrifugal compressor made of 34KHN1MA steel by heat treatment is proposed. Control of the finished product was carried out, including mechanical tests, microstructure studies, as well as non-destructive surface quality control.