Steel Belt Research Articles

A new insight into iron ore oxidized pellets prepared by steel belt roasting process

A new insight into iron ore oxidized pellets prepared by steel belt roasting process

A versatile steel belt casting equipment for in situ synchrotron radiation x-ray scattering measurement of polymer films.

A steel belt casting equipment, weighing approximately ∼6-7 tons and measuring ∼5m in length, has been designed and developed for simulating the industrial processing of polymer films and being combined with synchrotron radiation in situ x-ray scattering measurements. Through modification of its modules, it is feasible to implement two distinct film casting modes, namely the wet and the dry casting processes. The speed of a steel belt can span from 0.5 to 8 m/min. The highest experimental temperature and drying wind speed are 300 °C and 6m/s, respectively. All film casting parameters, such as extrusion speed, distance between die and steel belt, casting speed, temperature, and wind speed, can be adjusted independently. Especially, the control accuracy of the temperature and casting rate can reach ±0.1 °C and ±0.01 m/min, respectively. The feasibility of this equipment has been validated through in situ x-ray scattering tests at the BL10U1 industrial beamline of the Shanghai synchrotron radiation facility. With the assistance of this equipment, the understanding of the physical mechanism behind the film casting process should be improved so that the development of advanced functional polymer films.

Monocular-Vision-Based Method for Locating the Center of Anchor Holes on Steel Belts in Coal Mine Roadways

Monocular-Vision-Based Method for Locating the Center of Anchor Holes on Steel Belts in Coal Mine Roadways

A cylindrical shell model with distributed springs for a rotating tire

In a companion paper (Vol. 248, Article 108227), we demonstrated the dependence of tire parameters on the modal characteristics of a stationary tire. For a more realistic scenario, when tire rotation is considered, the modal characteristics are veered due to centrifugal, Coriolis, and gyroscopic effects. In this paper, we study the forced vibration response of a rotating tire and also consider the effect of static load on modal characteristics. The tire tread is modeled as a cylindrical shell and the sidewall is modeled using distributed springs in axial, circumferential, and radial directions. The tire inflation pressure is accounted for, which generates pre-stresses in the tire belt in circumferential and axial directions. The material model incorporates an orthotropic composite structure of the tire with multiple stacked layers of steel belt reinforcing. The governing equations of motion of the rotating shell are derived and further reduced to the corresponding eigenvalue problem. Galerkin’s projection with orthogonal basis functions is used to obtain the natural frequencies and associated mode shapes. For the forced vibration, the tire is excited by a harmonic point load at a fixed location, and the response is calculated by superimposing the basis functions of the free vibration problem. The analytical model predictions are compared against the computation finite element (FE) model developed in ABAQUS® and experimental modal testing results. To understand the effects of rotation on wave propagation, dispersion relations were obtained, and the wave number spectrum of the rotating tire was compared with that of the stationary one. Finally, to understand the dependence of natural frequencies on tire rotation and normal load, Campbell diagrams and frequency response functions (FRFs) were obtained from the proposed model. The model shows a fairly good agreement with experimental results and FE simulations.

Instability characteristics of surrounding rock and surrounding rock control technology of deep coal roadway crossing the fault: a case study of Zhuxianzhuang coal mine

To prevent severe damage to the surrounding rock of the roadway under the high ground pressure within deep mining, the stress evolution of the surrounding rock was studied, and the surrounding rock control technology in the II1057 roadway of Zhuxianzhuang Coal Mine before and after passing fault was conducted through theoretical analysis, numerical simulation and engineering practice. The results show that when the roadway is advanced to 20 m away from the fault, the surrounding rock is broken, cracks are generated at 2.56 m above the roof, and the advance abutment pressure of the roadway is 17–20 MPa. Through the borehole detection technology, the development of the internal cracks in the surrounding rock was observed, and the surrounding rock control technology scheme (the advanced grouting in front of the roadway and the active support of rock bolt + anchor cable + M steel belt + steel beam + metal mesh) was proposed. The engineering practice shows that the roof separation, roof-to-floor convergence and sidewall convergence are greatly reduced, and the mechanical properties of the surrounding rock of the roadway are greatly improved, leading to the effective control of the deformation of the roadway surrounding rock.

Research on the Positioning Method of Steel Belt Anchor Holes Applied in Coal Mine Underground

In order to improve the automation and safety of underground steel belt support in coal mines, a method for the intelligent identification and positioning of steel belt anchor holes in roadway support using inductive sensors is proposed. Using STM32F407ZGT6 as the main control chip, tasks such as data acquisition and processing, motor motion control, etc., are assigned based on the real-time operating system FreeRTOS. Using the XY mobile platform equipped with inductive sensors to detect steel belts, The collected data includes coordinate values and voltage values. Adaptive threshold generation and correction strategies are used for threshold segmentation and extraction of anchor hole boundary points. The principle of Hough circle transformation is used to fit the extracted boundary points into circles. The results show that this method can perform anchor hole positioning with a positioning error of within 5 mm, meeting the design requirements.

EMD-based noise reduction study of steel cored conveyor belt containing slag signal

This paper proposes a noise reduction technique that combines empirical mode decomposition (EMD) and wavelet thresholding to eliminate the noise interference caused by metal slag in the steel cord conveyor belt damage signal. Initially, the original signal undergoes decomposition by EMD into high- and low-frequency intrinsic mode function (IMF) components based on metal slag signal feature analysis. The wavelet threshold de-noising method is then applied to filter out the high-frequency noise while preserving the low-frequency IMF components. The IMF components containing slag noise are discarded, and the filtered signal and the low-frequency IMF components are used for signal reconstruction to obtain an optimal noise reduction effect. The study demonstrates that this method is more effective in suppressing metal slag noise, environmental noise, and other noise interferences than traditional EMD decomposition noise reduction and wavelet threshold noise reduction methods. This research provides a valuable reference for noise reduction in steel cord conveyor belt detection data.

Assessment of Different Methods for Enhancing Progressive Collapse Resistance of Irregular Reinforced Concrete Buildings Using Pushdown Analysis

Ensuring structures meet rigorous structural requirements is paramount in mitigating progressive collapse risk. In this comprehensive investigation, we scrutinize the impact of four distinct mitigation techniques on the propensity for progressive collapse in a six-story building featuring irregular structural attributes. The study adheres to the concrete building construction code ACI 318-14 and evaluates methods that include: (a) reinforcing the reinforced concrete (RC) slab with high-performance fiber-reinforced cementitious composites (HPFRCCs), (b) enhancing the RC slab with carbon fiber-reinforced polymers (CFRPs), (c) incorporating steel plate shear wall (SPSW) within specific columns, and (d) introducing an innovative approach named as the steel belt strip (SBS). In the context of 10 independent column loss scenarios conducted on the first floor, the nonlinear dynamic analysis reveals that HPFRCC effectively reduces vertical displacement under the removed column by up to 99.89% in certain scenarios. Meanwhile, the use of CFRP layers leads to reductions of up to 95% in vertical displacement, but with variations in effectiveness across scenarios. Notably, the SBS technique demonstrates remarkable potential by reducing vertical displacement by 97%, 89%, and 25.9% in different scenarios. This reduction, in conjunction with the mitigation of axial load on adjacent columns, makes the SBS a standout performer. Moreover, pushdown analysis indicates that, with the employment of these mitigation methods, the maximum loading factor can be increased up to 2.14 times in specific scenarios, significantly enhancing the structure’s resistance to progressive collapse. This pioneering research not only bolsters the resilience of irregular RC buildings but also holds profound implications for industry standards, risk assessment, and construction technology innovation.

Characteristics of surrounding rock damage and control technology of a facing-mining excavating roadway in north Shaanxi mining area

In a coal mine in the northern region of Shaanxi Province, China, a facing-mining excavating roadway exists, which is intended to be retained for subsequent working face safety services. This paper investigates the deformation and damage characteristics of the surrounding rock in different stages using FLAC 3D numerical simulation, taking the facing-mining excavating roadway of this coal mine as the research context. At 20 m ahead of the working face, a discontinuous plastic zone appears in the surrounding rock of the roadway, a phenomenon attributed to the varying hardness of the lithologyand termed 'plastic zone jumping.' The numerical simulation results have been were verified using drill hole peeping. Real-time monitoring of the roadway's stability is conducted on-site, showing that the roadway is significantly affected by mining at the 50 m point ahead of the working face. Based on the numerical simulation and on-site monitoring results, the support strength was increased at 50 m from the working face along the roadway, and a new support scheme was adopted. In the lagging section of the roadway, where mining pressure is strongly evident, differentiated reinforcement using anchor rods, anchor ropes, and W steel belts has been employed, resulting in a satisfactory on-site effect.

Parameters and surrounding rock control of gob-side driving under double key stratum after roof cutting

Taking the return-airway 4204 with roof cutting in Longquan Coal Mine as the engineering background, roof structure, key parameters, and deviatoric stress evolution were studied. Conclusion: The Key Stratum within a 4–8 times mining height is considered as Near Key Stratum. Cutting the roof makes it possible to form a cantilever structure of the Key Stratum on the solid coal side, which is more conducive to the stability of gob-side roadway. During cutting angle of 90–55°, the deviatoric stress increases linearly, and the increase rate is coal pillar > solid coal > roof > floor. While cutting length from 0 to 35 m, the deviatoric stress decreases linearly, and the decreasing range: coal pillar > solid coal > roof > floor. When coal pillar width is from 30 to 4 m, the deviatoric stress of left side and floor presents a “single peak” distribution. The deviatoric stress of coal pillar changes from an asymmetric “double peak” to a bell-shaped distribution, and the deviatoric stress of roof changes from a “single peak” to an asymmetric “double peak” distribution. Under same coal pillar width, the deviatoric stress of left, coal pillar and roof after roof cutting decreases most obviously, followed by the floor. Finally, the coal pillar width is 8 m, the cutting angle is 75°, the cutting length is 20 m, and the hole spacing is 1.0 m. The support scheme is bolt + metal mesh + steel belt + anchor cable combined support. The stable period of roadway is about 10 days.

Dynamics modeling and simulation of steel cord conveyor belt based on dynamic elastic modulus

Steel cord conveyor belts are widely used in long-distance transportation of various materials. The steel cord belt is composed of rubber and steel cord core, exhibiting excellent viscoelasticity and complex dynamic characteristics during operation. The existing static elastic modulus cannot accurately reflect the real dynamic properties of the conveyor belt. In this paper, based on the catenary theory, the formula for the dynamic elastic modulus of the conveyor belt is derived by introducing the sag and elastic deformation of the steel cord conveyor belt on the basis of the static elastic modulus. The dynamic modeling of the steel cord conveyor belt is carried out using rigid belt block element + flexible beam method. Then, the RecurDyn software is used to establish the dynamic simulation system of the belt conveyor and conduct simulations, which are validated through a test bench. The results show that dynamics simulation based on the dynamic elastic modulus is closer to the real dynamic characteristics of the belt conveyor. Finally, the dynamic characteristics of belt conveyors under different start-up times, different start-up speeds, and idler spacing are analyzed using this modeling and simulation method. The results demonstrate that the dynamic elastic modulus can accurately reflect the real dynamic properties of the conveyor belt, providing a more accurate dynamic modeling and simulation method for the design of belt conveyors.

Adhesion Reduction in Plastics Processing by means of laser-generated Microstructuring

Almost all production processes for manufacturing plastic or fiber reinforced plastic (FRP) components have in common that plastic and a steel surface are pressed together in the process. To avoid adhesion, the steel belts are coated with polytetrafluoroethylene (PTFE), ceramics or perfluoroalkoxy (PFA) during calendering, for example. However, the high temperatures of over 250 °C and the alternating mechanical load lead to damage of the coating. This results in adhesion of the coating to the product and loosening of the coating. Due to this, the surface quality of the organic sheets is reduced, and the production process is negatively affected.As the surface function can be controlled by material and surface patterns with different length scales (nm - µm), the surface topography of the belt steel was specifically modified in the roughness and microstructure level in order to reduce the adhesive interaction with the organic sheet. These microstructures were tested in extensive experiments and the results will be presented in this publication. True to the motto from nature to innovation, the micro- and nanostructured surface of the lotus leaf, which is provided with a fine substructure, was used as reference. The aim was to generate such a hierarchical structure by means of direct laser writing in order to avoid adhesions on production surfaces and to substitute the coating of steel strip surfaces. Additionally, a testing method close to the process was developed and evaluated to test the laser structured microstructures, which will also be presented.

Research on the tension of steel cord conveyor belts based on transverse vibration modelling

The accurate non-contact tension measurement of steel cord conveyor belt, an important load bearing medium, is critical for long distance belt conveyors. It is necessary to establish the relationship between the conveyor belt transverse vibration and the tension, in order to analyse the conveyor belt tension changes through indirect measurement of transverse vibration. The paper analyses the existing models of transverse vibration in conveyor belts, and finds that these models can hardly directly and accurately calculate the tension of the conveyor belt. Therefore, modifications are needed. Firstly, the paper establishes a dynamic model of the belt conveyor and conducts simulation analysis using RecurDyn software. This allows the authors to obtain the belt tension and transverse vibration displacement of the conveyor belt. Fast Fourier transform is employed to determine the vibration frequency, which is used to evaluate the vibration characteristics of conveyor belts under different operating conditions. Then, the paper conducts simulation analysis on the frequency and tension of the belt conveyor with different idler spacing, and performs nonlinear least squares calculation in MATLAB software to modify the coefficients of the transverse vibration model. This process involves nonlinear fitting, resulting in an improved transverse vibration model. Finally, the modified transverse vibration model is compared with the original model. The modified transverse vibration model can more accurately calculate the tension of the conveyor belt based on its vibration frequency. The validity of the modified model is verified by different types of conveyor belts.

Influence of tensile stress on the magnetic flux leakage signal of the coated steel belt

ABSTRACT The safety of coated steel belts (CSBs) is crucial for reliable elevator operation, as they are critical components in elevator systems. Magnetic flux leakage (MFL) testing is the preferred non-destructive method for evaluating CSBs due to its high sensitivity. Previous studies overlooked tensile stress's impact on in-service MFL testing of CSBs, potentially resulting in inaccurate defect assessments. This research aims to investigate the impact of tensile stress on the MFL signal of CSBs by developing a theoretical model, conducting finite element simulations, and performing experimental verification. In this paper, the rectangular edge defects are considered as the primary defect type in CSBs, and the applied stress on the CSBs varies from 30 MPa to 160 MPa. Under the above conditions, a linear relationship between MFL signal of CSBs and stress is established based on the simplified Jiles-Atherton model and magnetic dipole model suitable for CSBs. The finite element simulation and experiments further indicate that the MFL signal of CSBs increases linearly with the increasing tensile stress. The primary contributions of this study are establishing an MFL model suitable for CSBs and uncovering the linear relationship between the MFL signal of CSBs and tensile stress.

Application of EMD combined with wavelet algorithm for filtering slag noise in steel cord conveyor belt

This study proposes a noise reduction technique that combines empirical mode decomposition (EMD) with wavelet thresholding to remove noise interference generated by metal slag in the damage signal of steel cord conveyor belts. The initial step involves decomposing the original signal into high-frequency and low-frequency intrinsic mode function (IMF) components using empirical mode decomposition (EMD), guided by the metal slag signal characteristics analysis. The high-frequency noise is filtered away while the low-frequency IMF components are kept intact through the wavelet threshold de-noising technique. The slag noise-containing IMF components are deleted, and the filtered signal and the low-frequency IMF components are utilized for signal reconstruction to provide the optimum noise reduction result. The study demonstrates that this method is more effective in suppressing metal slag noise, environmental noise, and other noise interferences than traditional EMD decomposition noise reduction and wavelet threshold noise reduction methods. This research provides a valuable reference for noise reduction in steel cord conveyor belt detection data.

Support Optimization of Open TBM Tunneling in Luohe Formation Sandstone by CT Test and Numerical Simulation

As underground engineering extends into the western and deeper regions of China, more and more Luohe Formation sandstone layers will be encountered, which have weak cementation and high water content. It is a significant challenge to apply the open TBM, and the support system is crucial in determining whether TBM can excavate quickly and safely. Therefore, in order to optimize the support scheme, this paper analyzes the pore structure and porosity through CT scanning, the results indicate that the volume percentage of pores ≥34 μm is 2.3% and 1.5%, respectively, the large pore apertures are predominant, the surrounding rock has strong permeability, and there is a high risk of rock burst and roof collapse accidents, hence requiring reinforced support measures. On this basis, numerical simulations were conducted to evaluate the support effectiveness. The results show that replacing the “bolt + mesh” with a “bolt + cable + mesh + steel belt”, and replacing the top three bolts with 7.3 m anchor cables, can better control the deformation and provide sufficient thrust force for the TBM, ensuring excavation speed. After the implementation of this scheme at the Kekegai coal mine in Shaanxi, China, the TBM excavation speed increased by 70%, from the previous 10 m/day to 17 m/d, significantly reducing the project duration and construction costs.

Dynamic response and vibration modes of multi-layer wound cylindrical shell for hydrogen storage under external blast loading

Multi-layer wound cylindrical shells are the preferred structures for storage vessels working in high pressure and hydrogen atmosphere. However, they are susceptible to external blast loads from accidental hydrogen explosions. In order to study the response of such structures under external blast loading, a numerical model was developed, which combined a thermo-viscoplastic constitutive model and a fluid-structure coupling approach, and was subjected to external blast loads of different TNT equivalency weights. The strain responses and initial velocity fields of the structure were analyzed. A rigid-plastic theoretical model was also developed to calculate the maximum displacement of the inner shell and was compared with the simulation results. Moreover, the axial velocity vibration histories and dominant frequencies at different locations of the steel belts were numerically obtained. In addition, four vibration modes of the steel belts were presented in this paper. Furthermore, strain growth was observed in the high-frequency vibration area, and the possible reasons for the strain growth were analyzed and discussed in detail. The results will be useful for predicting the deformation modes of such multi-layer wound cylindrical shell structures under the risk of external hydrogen explosions.

Before and After: Evaluation of Microbial and Organic Loads in Produce Handling and Packing Operations with Diverse Cleaning and Sanitizing Procedures

Inadequate cleaning and/or sanitation (C/S) of food contact surfaces (FCSs) has been frequently reported during Produce Safety Rule inspections; however, limited data are available evaluating the effectiveness of C/S processes in produce operations. Different C/S practices were evaluated in four fresh produce operations for their efficacy in reducing microbial and organic loads on various FCSs. Microbial (aerobic plate counts; APC) and organic (ATP) loads were quantified during production, after cleaning, and after sanitizing, if applicable. Operations included: a berry packinghouse (BerryPK; wet cleaning), a blueberry harvest contractor (BerryHC; cleaning + sanitizing, C+S), and two mixed vegetable packinghouses (MixedV1; C+S, and MixedV2; rinsing + sanitizing, R+S). Following wet cleaning, significant reductions in APCs (p < 0.05) were seen on high-density polyethylene (HDPE) storage trays (n = 50) in BerryPK (3.1 ± 0.9 to 2.5 ± 0.7 log CFU/100 cm2). In BerryHC, a greater reduction in APCs was seen on HDPE harvest buckets (n = 25) following C+S (3.8 ± 0.5 to 1.1 ± 0.4 log CFU/100 cm2), compared to wet cleaning only in BerryPK. Stainless steel and conveyor belt FCSs (n = 16) in MixedV1 were sampled, and a significant reduction in APCs (p < 0.05) was observed when comparing in-use (4.8 ± 1.3 log CFU/100 cm2) to post-C+S (3.9 ± 0.7 log CFU/100 cm2). When similar FCSs (n = 17) were sampled in MixedV2, R+S also led to significant reduction in APCs (3.3 ± 0.6 to 1.9 ± 0.6 log CFU/100 cm2) (p < 0.05). ATP testing in fresh produce settings yielded inconsistent results, with no correlation between organic and bacterial loads detected during production (R2 = 0.00) across four operations, and weak correlations observed after cleaning (R2 = 0.18) and after sanitation (R2 = 0.33). The results from this study provide the foundational basis for future research on practical and effective C/S methods tailored to the produce industry.

Graphene-Based Flexible Strain Sensor Based on PDMS for Strain Detection of Steel Wire Core Conveyor Belt Joints.

Because of their superior performance, flexible strain sensors are used in a wide range of applications, including medicine and health, human-computer interaction, and precision manufacturing. Flexible strain sensors outperform conventional silicon-based sensors in high-strain environments. However, most current studies report complex flexible sensor preparation processes, and research focuses on enhancing and improving one parameter or property of the sensors, ignoring the feasibility of flexible strain sensors for applications in various fields. Since the mechanical properties of flexible sensors can be well combined with rubber conveyor belts, in this work polydimethylsiloxane (PDMS) was used as a flexible substrate by a simple way of multiple drop coating. Graphene-based flexible strain sensor films that can be used for strain detection at the joints of steel cord core conveyor belts were successfully fabricated. The results of the tests show that the sensor has a high sensitivity and can achieve a fast response (response time: 43 ms). Furthermore, the sensor can still capture the conveyor belt strain after withstanding high pressure (1.2-1.4 MPa) and high temperature (150 °C) during the belt vulcanization process. This validates the feasibility of using flexible strain sensors in steel wire core conveyor belts and has some potential for detecting abnormal strains in steel wire core conveyor belt, broadening the application field of flexible sensors.

Deformation and Dynamic Response of Steel Belt Staggered Multilayer Cylindrical Shell Under External Blast Loading

Abstract The deformation and dynamic response of a multilayer cylindrical shell composed of an inner shell and fourteen outer layers under external blast loads of different trinitro-toluene equivalency weights were studied. A numerical model using the thermo-viscoplastic constitutive model and considering fluid–structure coupling between explosion wave and structure was developed. The displacement in axial direction and cross section, as well as the effective strain responses, were analyzed to demonstrate the potential deformation of the shell structure. Results demonstrate that different materials cause inconsistent displacement and separation to develop in the inner and outer shells. In order to address the problem that the displacement of the inner shell is hard to measure due to the shielding and covering of the outer shell, a theoretical formula for calculating the maximum displacement of the inner shell was developed. The deflection process and stress triaxiality histories of the inner shell were investigated, and the results showed that compressive stress is the primary cause of plastic deformation. Additionally, the delamination that appeared in the outer shell was discussed, and it was revealed that there are two factors of delamination: (1) Stress waves spread across adjacent layers in the opposite direction because steel belts were wound in the opposite direction between the two adjacent layers; (2) Outer layers experienced uneven compressive loads. The results will be helpful to provide a reference for the intrinsic safety design of such multilayer cylindrical structures for hydrogen storage, etc.