Steel Works Research Articles

Heat Stress among Steel Workers in Al Jubail,Saudi Arabia

Background: Workers working in the steel industry has commonly exposed to heat which lead to health risk. The objective of this study was to assess heat stress among steel production workers. Materials and Methods: It is a cross sectional study, 186 workers were selected through simple random sampling. There are two groups of workers staff and line production. The Wet Bulb Global Temperature (WBGT) index was measured from Heat Stress Monitor (Casella Micro herm WBGT) and Heat Strain Score Index (HSSI). Spearmen correlation for determine the correlation between WBGT and HSSI and association between risk factors and HSSI determined through logistic regression. Results: The mean and SD values of the wet bulb global temperature was 32.46 (2.01) and these values exceed Threshold Limit Values (TLV by American Conference of Governmental Industrial Hygienists (ACGIH) standard and HSSI scores showed that 24.3% of the exposed workers were in red dangerous zone (severe heat strain). The WBGT and HSSI values are positively correlated (r = 0.85) (P = 0.001). Risk factors associated with heat stress after adjustment are age 19-35 years (OR 6.07, CI 1.78-21.90), years of experience >10 years (OR 4.67. CI 1.23-18.42), ever smoking (OR 1.58, CI 1.08-4.57) and overweight (OR 1.56, CI 1.20-12.48). Conclusion: The finding of this study showed that heat stress is common hazard among steel workers and the heat conservation planning intervention action should be conducted to reduce exposure.

Анализ и перспективы развития методических подходов к планированию работ по капитальному ремонту магистральных нефтегазопроводов

The article presents defined scientific basis for planning repair-recovery works on trunk oil and gas pipelines, based on obtaining data about technical condition of pipelines and joined analysis of reliability indicators, safety and risk indicators with regards to material and technical opportunities of operating company and strategic characteristics of facilities. The article contains consolidated scientific opinion about the methods for planning repair-recovery activities on pipelines of Russia, USA and Europe. It is noted, that the approaches, implemented in real life, can differ from scientific basis due to a variety of causes. On the basis of the outlined concept, the analysis of practical approaches, applied for planning of overhauls of trunk gas and oil pipelines in Russia, was performed. The specialists use high technology analytical system to initiate remedial measures, focusing on reliability parameters and considering economic feasibility. However, what we consider promising is the extension of organizational and technical basis with the purpose of obtaining volume of statistic and actual source data, necessary for expert assessment. The planning of replacement of trunk pipeline sections is based on the results of continuous monitoring of the technical condition of the pipes by smart pigging and the involving into calculation both actual parameters of facilities operation and actual mechanical characteristics of pipe metals and welded connections, considering overall influence of specific production technology, steel work quality and service life length. With the purpose of further developing this approach, it is practical to extend the list of considered defect parameters and the use of the whole system of the pipeline technical condition data by adding the quantity of hours in service up to the failure in a probable scenario. The author stated the primary directions of developing methodical approaches to arranging the technical maintenance and repair of oil and gas pipeline for long-term operation.

Grain Damage in Low­Speed Collision with the Surfaces of the Hoisting­and­Transport Machines Working Parts

To reduce the damage level of wheat grains during its post-harvest processing, it is proposed to replace steel working parts in lifting and transporting machines with polymer ones. ( Research purpose ) Experimentally determine the dependence of the degree of wheat grain damage on the number of collisions, the incidence angle and the hoisting-and-transport machines working parts surface material when the grain moves at a speed of up to 3.5 meters per second. ( Materials and methods ) Experiments were carried out on a unit that reproduced the low-speed collision conditions of wheat grains with a smooth steel or plastic surface plate at various angles of incidence and the number of impacts. ( Results and discussion ) The authors identified a significant reduction in grain damage in a collision with a plastic plate compared to a steel plate – by 8-10 percentage points – is observed only at incidence angles of 60-90 degrees and the number of strokes from 5 to 10. It was found that at incidence angle up to 60 degrees, the specified difference didn’t exceed 4 percentage points and reached zero at an angle of 45 degrees. The low efficiency of replacing steel working parts with plastic ones to reduce grain damage when driving at low speed was explained by the weak manifestation of the decrease effect in the potential energy of grain deformation upon impact on a plastic surface at a collision low speed. ( Conclusions ) The authors determined that when grains moved at a speed of less than 3.5 meters per second in a rarefied stream without interaction between them, when individual grains collided with the hoisting-and-transport machines working parts, replacing steel working parts with plastic ones was impractical.

Effect of occupational factors on pre-diabetes mellitus among iron and steel workers

Objective: To investigate the prevalence of pre-diabetes mellitus (PDM) and the impact of occupation-related factors on PDM, among workers from a steel company in Tangshan city, Hebei province. Methods: Clustering sampling method was used to select a steel company and to carry out occupational health-related physical checkup programs for eligible workers who had working in this company for longer than one year. The study began in February and ended up in June, 2017. Workers who were with FPG level as ≤6.9 mmol/L, and free from diabetes, were selected as the subjects for this study. Questionnaires were used and physical examinations and FPG testing conducted. Results: The total number of subjects in this study was 4 173, of which 2 648 appeared as pre-diabetic, with the prevalence rate as 63.4%. Increase of the PDM prevalence was in parallel with the length of service, among the workers. The risk for the pre-diabetes in those who worked more than 8 hours per day was 1.696 times higher than those who worked less than or equal to 8 h/d (95%CI:1.517-1.937). Compared with those workers without exposures to heat, noise or carbon monoxides, the proportion of pre-diabetes appeared higher in workers exposed to heat, noise or CO with OR=1.782 (95%CI: 1.205-2.636), 1.815 (95%CI: 1.209-2.794) and 1.653 (95%CI: 1.158-2.361), respectively. Risks for those who were exposed to heat or noise were higher than those who were free from exposure to any occupational hazards (OR=2.098, 95%CI: 1.296-3.397). Prevalence rates of pre-diabetes in those who were exposed to heat, noise or CO, were higher than that those who were not. Conclusion: Working hours and exposures to heat, noise or CO appeared as influential factors on PDM.

Blast Analysis on In-Filled Steel Tube Columns

In recent years, a large number of studies have been carried out to investigate the behaviours of concrete filled double skin steel tube (CFDST) members due to its increasing popularity in the construction industry. This project aims to study on ultra-high performance concrete filled double-skin tubes subjected to blast loading with cross section being square for both inner and outer steel tubes using ANSYS software. It is evident that the proposed CFDST column was able to withstand a large blast load without failure so that it has the potential to be used in high-value buildings as well as critical infrastructures. The steel tubes and concrete work together well and integrity of steel concrete interface is maintained. Steel tubes in inner and outer can acts as permanent formwork and primary reinforcement. ANSYS results shows that the CFDA column can withstand applied blast load.

Investigations on bending of micro-thin sheets using spark discharges

ABSTRACT In today’s world, micro-manufacturing techniques are getting developed day by day to minimize the effort and sophistication to provide desired products. Micro forming is one of the micro-manufacturing techniques. Present research article reports on the bending of micron-thin sheets using an electric discharge machining process. The spark discharges were used to bend thin stainless steel work materials. Bend angle (BA) was analyzed by varying the duty factor (DF), gap voltage (GV), and peak current (PC). In the present work of research, response surface methodology (RSM) was implemented for the design of experiments. BA was measured using an optical microscope. The ANOVA outcomes showed that the BA was affected by all the input parameters at a 95% confidence level. Maximum value obtained for the BA was 23.76° at duty factor 70, voltage 40, and peak current 10 A. In contrast, the minimum was 4.62° at duty factor 30, gap voltage 40 and peak current 6 A. The bending surface was analyzed by Energy-Dispersive X-Ray Spectroscopy (EDS) and Field Emission Scanning Electron Microscope (FESEM) images. The EDS results confirmed the deposition of the tool material over the sample; also, FESEM images showed micro-cracks, holes at machined surface.

659-P: Effect of Coaching en Diabetes (CoeD) Program on Glycemic Control in Steel Workers with Type 2 Diabetes

Patients with type 2 diabetes (T2D) could improve its glucose control with a multidisciplinary cultural management. Coaching en Diabetes (CoeD) is a multicomponent program for steel workers and their direct families with T2D when their A1C is >9% as an effort to increase attachment to medical treatment. The program focusses on the empowerment and glucose treatment sensibilization through a group medical visit, improvement of self-management and medical treatment. CoeD is performed by a multidisciplinary team (internist, nutritionist, diabetes educator, social worker, etc.). The aim of this study is to evaluate the effect of this program in glycemic control through 2 years of follow-up. This is a retrospective and longitudinal study of patients with uncontrolled T2D at Clinica Nova from Monterrey, Mexico. This study was conducted from May 2017 to 2019. We used descriptive statistics and ANOVA of repeated measures when it was appropriate. We included a total of 153 [115 (75.2%) males], with a mean (SD) age of 62.9 (11.2) years. The duration of T2D was 9.7 (6.6) years. During the follow-up 26 patients (17%) left the program, 2 of them died in relation to cardiovascular disease. All patients maintained a controlled blood pressure. We found a reduction of A1C of 1.5% [Mean (SD) 9.8% (1.5) to 8.3% (1.6), p=0.032) and fasting glucose of 41.8 mg/dl [Mean (SD) 180mg/dl (67) to 138.2mg/dl (55), p=0.021). These reductions were maintained through the 24 months of follow-up. The CoeD program was successful in reducing and sustaining A1C and pre-prandial glucose reduction in this group of patients. Disclosure M. Romero-Ibarguengoitia: None. O.M. Cantu Santos: None. D. Gutierrez Gonzalez: None. R. Gonzalez Facio: None. A. Gonzalez-Cantu: None.

Life cycle assessment of refractory waste management in a Spanish steel works

A life cycle assessment (LCA) is conducted on the current refractory waste management practices in a steel works in Spain producing around 6,000 tonnes of refractory waste in 2018. Management practices included direct reuse of spent magnesia-carbon (MgO-C) bricks, recycling of MgO-C bricks and high-alumina refractories by an external contractor and landfilling of monolithics and isostatic refractories, for which there were yet no established valorization routes. This current situation was compared to a hypothetical scenario where all refractories were disposed in landfill. The LCA included waste management activities (collection, transport, treatment) as well as production of substituted primary materials (dead-burned magnesia, calcined bauxite and new MgO-C bricks) produced in China and Germany. Results are discussed for four indicators: greenhouse-gas emissions, Non-renewable energy demand, land use and water use. Overall, per tonne of produced waste, the current management leads to a reduction or saving of 0.54 tonnes CO2-eq, 3 GJ primary energy from non-renewable sources, the occupation of 10 m2 of land during one year and the abstraction of 5 m3 freshwater. The results also show that reuse, in the particular case of spent MgO-C bricks, leads to higher benefits than recycling by At least a factor four. The robustness of these results is confirmed through the application of a Monte Carlo uncertainty analysis, as well as a sensitivity analysis focusing on a shift from coal to natural gas in the Chinese refractory industry.

Relationship between occupational noise exposure and hypertension in male steel workers

To analyze the effect of occupational noise exposure on hypertension in male steel workers. The general information, noise exposure and blood pressure were collected through questionnaires and physical examinations. Chi-square test was used to investigate the prevalence of hypertension under different cumulative noise exposure, and the effect of noise exposure and other factors on hypertension was analyzed by the restrictive cubic spline(RCS) combined with multivariatenon-condition Logistic regression model. The prevalence of hypertension in noise exposure group was higher than that in noise non-exposure group(P<0. 001). After adjusting for multiple factors, the restricted cubic spline model showed a dose-response relationship between cumulative noise exposure(CNE) and hypertension(overall correlation χ~2=75. 76, P<0. 001, and nonlinear χ~2=24. 17, P<0. 001). Compared with the steel workers exposure to lowest dose, the risk of hypertension of steel workers exposure to 82-94 and 95-107 dB(A) in group was 1. 81(95%CI 1. 31-2. 52) times and 2. 60(95%CI 1. 84-3. 68) times. There is a non-linear dose-response relationship between cumulative noise exposure and hypertension.

Algorithms and software for optimal management of raw materials, fuel and energy resources in blast furnace production

The structure of optimization model of optimal management of raw materials, fuel and energy resources in the blast-furnace shop of iron and steel works is represented. The following blocks are taken as system basis: 1) calculation of the set of parameters that characterize the thermal, gas-dynamic, slag and blasting modes for every blast furnaces of the shop during the base period; 2) calculation of linearized model coefficients (constants of transferring via different exposure pathways) individually for every blast furnace as well as properties of iron ore raw materials, fluxing additions, blasting parameters, parameters of fuel-enriched blast influencing the technical-and-economic indices of separate furnaces performance, their thermal, gas-dynamic and slag operation modes in the course of blast-furnace melting according to UrFU-MMK blast-furnace production model within the base period; 3) solution of tasks that consider the optimal allocation of raw materials, fuel and energy resources for the project period of blast furnaces operation; 4) analysis of obtained results and providing of recommendations on the optimization of blast furnaces parameters. The developed functional model of optimal distribution of raw materials, fuel and energy resources for the engineering and technology personnel of blast-furnace shop is illustrated; the main functions and interconnections between the separate functional blocks are defined. The functions of created “Optimal management of raw materials, fuel and energy resources in the blast-furnace production” software that is realized in the Microsoft Visual Studio 2017 (C# programming language) programming environment in the form of web application are pointed out. The program product provides the engineering and technology personnel of blast furnace shop of iron and steel works with the opportunity to solve the tasks of optimal distribution of fuel and energy resources (natural gas and oxygen consumption) within the group of blast furnaces in the different technological situations.

A Mon Valley Memoir: How Steelworkers in Homestead Went Down Fighting in the 1980s

A Mon Valley Memoir: How Steelworkers in Homestead Went Down Fighting in the 1980s

Electrical drives of continuous casting machine withdrawal rolls: a model and practical implementation of limitations on longitudinal forces in billets

The research is aimed at increasing the quality of a concast billet macrostructure by limiting static and dynamic longitudinal forces created in billets by electrical drives of withdrawal rolls during wear and bending of the withdrawal roll body and random and periodic slips of drives. The paper analyzes process requirements for electrical drives of withdrawal rolls: contains a procedure for calculating dynamic longitudinal forces created in billets by drives of withdrawal rolls, determines whether influence of operating modes of the said drives on changes in billet withdrawal force is relevant, contains developed techniques and algorithms of withdrawal roll drive automated control limiting static and dynamic longitudinal forces in billets, and includes the experimental analysis of efficiency of methods and technical solutions on operating drives. Research was carried out at the Russian large iron and steel works. When performing the research, the authors applied analytical and numerical methods of solving algebraic and differential equations and systems, methods for structural modeling. As a result of the research, the authors developed and experimentally confirmed methods for “soft” restoring of the contact between the withdrawal roll and the billet and adjusting phases of fluctuating changes in load currents of motor groups. The obtained results are transferred as technical specifications and taken for introduction, when revamping electrical equipment of existing continuous casting machines. Results of mathematical simulation and experimental research are used to design automated electrical drives of withdrawal rolls in the secondary cooling zone of the bow-type continuous casting machine. Impact dynamic loads were decreased by 3 times, resulting in an average increase of 8% in the quality of the billet center with regard to all types of defects.

Design and optimization of electrochemical cell potential for hydrogen gas production

Abstract This study deals with the optimization of best working conditions in molten melt for the production of hydrogen (H2) gas. Limited research has been carried out on how electrochemical process occurs through steam splitting via molten hydroxide. 54 combinations of cathode, anode, temperature and voltage have been investigated for the optimization of best working conditions with molten hydroxide for hydrogen gas production. All these electrochemical investigations were carried out at 225 to 300°C temperature and 1.5 to 2.5 V applied voltage values. The current efficiency of 90.5, 80.0 and 68.6% has been achieved using stainless steel anodic cell with nickel, stainless steel and platinum working cathode respectively. For nickel cathode, an increase in the current directly affected the hydrogen gas flow rate at cathode. It can be hypothesized from the noted results that increase in current is directly proportional to operating temperature and applied voltage. Higher values were noted when the applied voltages increased from 1.5 to 2.5 V at 300°C, the flow rate of hydrogen gas increased from 1.5 to 11.3 cm3 min−1, 1.0 to 13 cm3 min−1 in case of electrolysis @ stainless steel and @ graphite anode respectively. It is observed that the current efficiency of stainless steel anodic cell was higher than the graphite anodic cell. Therefore, steam splitting with the help of molten salts has shown an encouraging alternate to current methodology for H2 fuel production.

Techno-economic evaluation of methanol production using by-product gases from iron and steel works

Aiming at achieving large-scale CO2 mitigation in the iron & steel industries via efficient utilization of the by-product gases such as the coke oven gas (COG) and Linz-Donawitz converter gas (LDG) in the iron & steel works, conceptual design of a LDG-to-methanol process (option 1) and two LDG/COG-to-methanol processes (options 2 and 3 without or with H2 purification, respectively) was implemented using the process simulator Aspen Plus. Both the process development and economic analysis for all the three proposed options were conducted to determine the technical performance via indicators such as the energy efficiency and CO2 reduction rate, and the profitability via indicators such as the total capital investment and the net methanol production cost. Meanwhile, six case studies under different recycle ratios (0.5–0.95) were conducted for each proposed option to investigate the effects of recycle ratio on the technical and economic performance. The techno-economic analysis results clearly show that all the three proposed options are highly efficient for CO2 mitigation via methanol production using the by-product gases LDG and COG. More specifically, options 1 and 3 seem to be more energy efficient and eco-friendly than option 2, in terms of energy efficiency and CO2 reduction rate. Whereas, options 2 and 3 seem to be more economically feasible than option 1, considering the net methanol production cost. From the aspects of both technical and economic performance, option 3 is considered as the most competitive process. This work provides candidate process routes for the iron & steel industries to become more sustainable and profitable, especially in the event of a high carbon tax and a low H2 price in the future.

Occupational heat stress induced health impacts: A cross-sectional study from South Indian working population

Rising temperature and heat stress risks in the changing climate scenario might potentially affect workers globally, especially the ones with strenuous workload in tropical settings. We used a cross-sectional study design to profile the heat exposures of ∼1900 workers from eight industrial sectors using a QuesTemp Wet Bulb Globe Temperature (WBGT) monitor, quantified select heat-strain indicators viz., rise in Core Body Temperature, Sweat Rate, and Urine Specific Gravity and evaluated the perceived health impacts of heat stress using a structured questionnaire. Heat exposures (average WBGT: 30.1 ± 2.6 °C) exceeded the Threshold Limit Value for 67% workers and was positively associated with the rise in Core Body Temperature >1 °C in 13% and elevated Urine Specific Gravity >1.020 in 9% workers. Heat-related health concerns were reported by 86% workers, and the heat-exposed workers had 2.3 times higher odds of adverse health outcomes compared to unexposed workers (p < 0.0001). Exposure to higher WBGT and adverse renal health among salt-pan workers were significantly associated (p = 0.004), and steel workers had 9% prevalence of kidney stones. Evidence presented clearly points to heat stress as a health and productivity risk factor that could have long-term and irreversible health impacts. In-depth assessments are urgently needed to develop scientifically sound preventative interventions and protective labor policies to avert the adverse occupational health and productivity consequences for millions of workers globally, thereby aiding poverty reduction.

The Influence of Work Roll Material on the Corrosion Behavior of Hot-Rolled Aluminum-Manganese Alloys

The tribological impact of the steel alloy employed as the work roll material during hot rolling on the surface quality and corrosion behavior of Al-Mn alloys was explored. AISI 52100, AISI D2 and AISI 440C steel work rolls with a surface roughness (Ra) of 0.1 µm were used to hot roll Al-Mn alloy specimens under similar conditions using a rolling tribo-simulator. Corrosion tests were then performed on the rolled Al-Mn specimens by immersing them in a 0.5 wt.% NaCl solution. Surface examination of the Al-Mn specimens after rolling revealed dark MgO-rich islands covering the surfaces of the AISI D2 and AISI 440C-rolled Al-Mn surfaces. These features were associated with the carbides observed protruding from the AISI D2 and AISI 440C steel surfaces. Subsequent corrosion tests revealed that these MgO-rich islands possessed a distinct influence on the corrosion behavior of the rolled Al-Mn surfaces. The frequency of occurrence and depth of the MgO-rich islands, which were dependent on the work roll material employed, influenced the initial and subsequent corrosion morphology detected on the Al-Mn surfaces. The preferential dissolution of the MgO-rich islands was detected as one of the corrosion mechanisms occurring during the early stages of corrosion.

Job category differences in the prevalence and associated factors of insomnia in steel workers in China.

This study aimed to investigate the prevalence of insomnia and risk factors among different job categories of steel workers in China, in order to improve their quality of occupational life. A cross-sectional face-to-face survey was conducted which involved 5834 steel workers from a large enterprise located in northern China, including front-line, maintenance and inspection, and other auxiliary workers. The Athens Insomnia Scale and the Job Content Questionnaire were used to assess the status of insomnia and job stress/social support, respectively. Multivariable logistic regression was used to identify factors influencing insomnia. The overall prevalence of insomnia was determined at 42.0% (95% confidence interval: 40.7%-43.2%). For front-line, maintenance and inspection, and other auxiliary workers, the prevalence was 42.3%, 39.8%, and 47.9% (p = 0.001), respectively. The participants with high stress and low support, and those who had experienced ≥2 major life events in the past 12 months, compared to those with low stress and high support, and those without major events, displayed an increased risk of insomnia among all 3 job categories (the adjusted odds ratio ranged 1.56-2.38 and 1.30-1.75, respectively). The educational level, shift work, alcohol consumption, and present illness were identified as influencing factors of insomnia for 1 or 2 job categories. The prevalence of insomnia was the highest in the group of other auxiliary steel workers among the 3 job categories of steel workers under consideration. While the influencing factors of insomnia differed among the groups, job stress and major life events were common risk factors of insomnia among the 3 categories of steel workers. Int J Occup Med Environ Health. 2020;33(2):215-33.

Measurements and calculations of the equilibrium adsorption amounts of CO2\u2013N2, CO\u2013N2, and CO2\u2013CO mixed gases on 13X zeolite

Pressure swing adsorption (PSA) is one practical process for CO2 separation from the exhaust gases in various industries, such as blast furnace gas in steel works. For optimum design of the PSA process, precise estimation of the adsorption equilibrium of mixed gases is desired. The ideal adsorbed solution (IAS) model is a reliable model for this estimation. However, the IAS model requires convergent calculations, which significantly increase the calculation load, especially in dynamic PSA simulations. An analytical formula such as the extended Langmuir (EX-LM) equation is more useful for calculation of the equilibrium adsorption amounts of mixed gases. A drawback of this equation, however, is the uncertainty of the thermodynamic consistency and consequently the accuracy of the calculation results. In order to clarify the necessary conditions for application of the EX-LM equation as an approximation of the IAS model with Langmuir equation (IAS-LM model), both the analytical features and the estimation accuracy of these different methods were evaluated. To evaluate the accuracy of the equations, the equilibrium adsorption amount of mixed gases consisting of CO2, N2, and CO, which are the major gas components of blast furnace gas in steel works, on 13X zeolite were measured experimentally. The results confirmed that the accuracy of the EX-LM equation varies depending on the gas pressure and also the affinities of the adsorbates. Under higher gas pressure conditions, more reliable calculation results were obtained by the IAS-LM model.

The Effects of High-Speed Steel Roll and Lubrication on Work Roll Wear and Fatigue During Electrical Steel Strip Hot Rolling

Work rolls in the hot strip mill withstand extreme service conditions, especially when electrical steels are rolled, resulting in severe roll wear and fatigue. High-speed steel (HSS) work rolls and rolling lubrication are applied to the mill to improve roll wear and fatigue. Tests show that HSS work rolls manifest good performance in wear, fatigue and oxidation resistance during electrical steel hot rolling. The wear loss of HSS work rolls decreases remarkably, but the heat dispersion deteriorates. The service period of HSS work rolls can be increased significantly, but the fatigue failure risk increases as well. In addition, rolling lubrication is proven to be effective in alleviating roll wear and fatigue, but high temperature reduces the positive effects of rolling lubrication. Roll wear and fatigue are considered to be parallel and mutual effective processes. The applications of HSS rolls together with rolling lubrication contribute the most to the improvement of work roll wear and fatigue during electrical steel hot rolling.

Theoretical Assessment Of The Bearing Capacity Of A Steel Beam Reinforced With Carbon Fiber

To reinforce steel beams, modern carbon fiber materials that are attached to the beam from the stretched side using a special two-component adhesive can be effectively used. Compared to traditional methods of cross-section increase by means of additional steel elements attached by welding or on bolts, reinforcing with carbon fiber plastic has a number of advantages. Carbon plastic has a much smaller weight than a steel element that has the same load-bearing capacity; the adhesive layer prevents corrosion of the reinforced element; work on strengthening is carried out in a short time and with less labor expenditures etc. The article presents the results of theoretical studies of beams reinforced with carbon fiber lamellas. For the theoretical assessment of the strength of a reinforced steel beam, deformations and stresses in the section at the elastic, elastic-plastic and plastic stages of steel work are considered. It is established that a significant effect of carbon fiber reinforcement is observed even when the stresses in it are determined by the strength of the adhesive joint. Formulas, taking into account the strength of the adhesive layer determined experimentally, for determining the strength of a reinforced beam are obtained. A theoretical model of the operation of bent steel elements is constructed and theoretical dependencies are obtained that can be used for calculations of steel beams reinforced with carbon plastic.