Safety assessment of sand casting explosion accidents through on-site testing and numerical simulation of the temperature variation in sand molds to protect employee health

Sand casting operations, though commonplace, pose a significant threat of explosion accidents. This paper presents a novel sand casting safety assessment technique based on fault tree analysis, Heinrich accident triangle, hazard and operability–layer of protection analysis (HAZOP–LOPA) and bow tie model components. Minimal cut sets and minimal path sets are first determined based on fault tree analysis, then the frequency of sand casting explosion accidents is calculated based on the Heinrich accident triangle. Third, the risk level of venting quality can be reduced by adopting HAZOP–LOPA; the residual risk level of venting quality remains excessive even after adopting two independent protective layers. The bow tie model is then adopted to determine the causes and consequences of venting quality. Five preventative measures are imposed to enhance the venting quality of foundry sand accompanied by 16 mitigative safety measures. Our results indicate that the risk attributable to low foundry sand venting quality can be minimized via bow tie analysis.

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Numerical Simulation of Filling and Solidification in Sand Casting by Procast

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.791-793.550 ◽

2013 ◽

Vol 791-793 ◽

pp. 550-553 ◽

Cited By ~ 1

Author(s):

Dong Dong Han ◽

Cheng Jun Wang ◽

Juan Chang ◽

Lei Chen ◽

Huai Bei Xie

Keyword(s):

Numerical Simulation ◽

Heat Dissipation ◽

Solidification Process ◽

Simulation Software ◽

Sand Casting ◽

Production Costs ◽

Raw Material ◽

Casting Defects ◽

Three Dimension ◽

Filling And Solidification

At present, pulley produced in China has been able to meet the demand of domestic and international markets. But there are many problem of the pulley industry in our country, such as too many production enterprises and the low level of export products. And as components of drive system are light weight and raw material price of pulley casting are rising, manufacturing requirements of the pulley are also more and more high. Aiming at the casting defects of pulley that enterprise current product, pulley casting blank model of common material HT250 be made by three-dimension software, numerical simulation of filling and solidification process for pulley sand casting by the casting simulation software Procast, the size and location of the various casting defects were forecasted and analyzed, reflecting the pulley filling and solidification process of the actual situation, due to the thicker pulley rim and less heat dissipation, position of shrinkage is close to the middle of rim [, a method of eliminating defects is proposed to realize sequential solidification, and thus to minimize porosity shrinkage and improve casting performance and reduce casting time and reduce production costs.

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Simulation and Analysis of Swing Motion of Lifting Load System on Rescue Vehicle

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.538-541.725 ◽

2012 ◽

Vol 538-541 ◽

pp. 725-729

Author(s):

Han Ming Liu ◽

Heng Zhao ◽

Ning Li

Keyword(s):

Numerical Simulation ◽

Theoretical Basis ◽

Safety Assessment ◽

Kinematic Model ◽

Excitation Frequency ◽

Lagrange’S Equation ◽

Set Up

In lifting, remoted operated dive vehicle（ROV） may swing with the effect of wave. Based on the general form of Lagrange’s equation, a 3-DOF nonlinear swing motion kinematic model was set up. The kinematic response was studied using methods of numerical simulation. The results demonstrated that the kinematic response depends on the length of cable, lifting speed and excitation frequency. Conclusions drawn from this work can be used for safety assessment and theoretical basis for lifting ROV.

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Numerical Simulation of Sand Casting of an Aluminium Part

DAAAM Proceedings - Proceedings of the 22nd International DAAAM Symposium 2011 ◽

10.2507/22nd.daaam.proceedings.221 ◽

2011 ◽

pp. 0445-0446

Author(s):

George Christopher Vosniakos ◽

Anastasia Vassiliou ◽

Spyridon Tsekouras

Keyword(s):

Numerical Simulation ◽

Sand Casting

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Safety Assessment of Casting Workshop by Cloud Model and Cause and Effect–LOPA to Protect Employee Health

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph17072555 ◽

2020 ◽

Vol 17 (7) ◽

pp. 2555 ◽

Cited By ~ 1

Author(s):

Qingwei Xu ◽

Kaili Xu ◽

Fang Zhou

Keyword(s):

Safety Assessment ◽

Cloud Model ◽

Least Square Method ◽

Assessment Method ◽

Employee Health ◽

Least Square ◽

Entropy Weight ◽

Safety Level ◽

Cause And Effect ◽

Assessment Approach

Safety assessment of a casting workshop will provide a clearer understanding of the important safety level required for a foundry. The main purpose of this study was to construct a composite safety assessment method to protect employee health using the cloud model and cause and effect–Layer of Protection Analysis (LOPA). In this study, the weights of evaluation indicators were determined using the subjective analytic hierarchy process and objective entropy weight method respectively. Then, to obtain the preference coefficient of the integrated weight more precisely, a new algorithm was proposed based on the least square method. Next, the safety level of the casting workshop was presented based on the qualitative and quantitative analysis of the cloud model, which realized the uncertainty conversion between qualitative concepts and their corresponding quantitative values, as well as taking the fuzziness and randomness into account; the validity of cloud model evaluation was validated by grey relational analysis. In addition, cause and effect was used to proactively identify factors that may lead to accidents. LOPA was used to correlate corresponding safety measures to the identified risk factors. 6 causes and 19 sub-causes that may contribute to accidents were identified, and 18 potential remedies, or independent protection layers (IPLs), were described as ways to protect employee health in foundry operations. A mechanical manufacturing business in Hunan, China was considered as a case study to demonstrate the applicability and benefits of the proposed safety assessment approach.

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Land Surface Temperature Variation Following the 2017 Mw 7.3 Iran Earthquake

Remote Sensing ◽

10.3390/rs11202411 ◽

2019 ◽

Vol 11 (20) ◽

pp. 2411

Author(s):

Zhu ◽

Jiao ◽

Shan ◽

Zhang ◽

Li

Keyword(s):

Numerical Simulation ◽

Surface Temperature ◽

Temperature Variation ◽

Observational Data ◽

Land Surface Temperature ◽

Crustal Deformation ◽

Land Surface ◽

Projection Area ◽

Fluid Migration ◽

Seismic Slip

During an earthquake, crustal deformation, fluid flow, and temperature variation are coupled; however, earthquake-related land surface temperature (LST) variations remain unclear. To determine whether post-seismic fluid migration can cause changes in LST, and taking the Mw 7.3 2017 Iran earthquake as an example, we modeled surface cooling (CA) and warming (WA) areas induced by co-seismic slip and fluid migration using a thermo-hydro-mechanical (THM) coupled numerical simulation. Moreover, using nighttime LST data with 15-min resolution, the daily attenuation coefficient k of nighttime LST was extracted by attenuation function fitting, and the trend of the k time series was analyzed using the Mann–Kendall and Sen’s methods. Based on the comparison of k trends between the post-seismic and 2010–2016 periods, we obtained cooling and warming trends for the modeled CA and WA. The numerical simulation and observational data show good consistency, and both indicate that fluid migration caused by crustal deformation can lead to changes in LST. The numerical simulations show that after the Iran earthquake, the surface projection area of co-seismic slip correlated with a cooling area (CA), while the surrounding area correlated with a warming area (WA). For the LST observational data, the post-seismic k trends of the calculated CA and WA are positive and negative, indicating sustained cooling and warming processes, respectively. This study provides evidence that LST variation is caused by co-seismic crustal deformation and fluid migration and reveals the coupled evolution of deformation, fluid, and temperature fields. The results provide new insights into the mechanisms of seismic thermal anomalies.

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