12 research outputs found
SELECTION OF TOOL GEOMETRY IN REGARD TO MATERIAL BEHAVIOR DURING DEFORMATION PROCESS
U ovome istraživanju analizira se ponašanje lima X5CrNiMo17-12-2 tijekom procesa dubokog izvlačenja. Prikazana su mehanička i kemijska svojstva ispitivanog lima dobivena pomoću spektrometrije i standardnog vlačnog testa. U radu je ispitan osnovni proračun koji daje dobru pretpostavku očekivanog ponašanja materijala prilikom oblikovanja ulaznog uzorka u konačni oblik. Na temelju mehaničkih svojstava izvedena je simulacija ponašanja materijala metodom konačnih elemenata u softveru ABAQUS. Rezultati proračuna matematičkog modela alatne geometrije u ovisnosti o ponašanju materijala i simulacije su uspoređeni.This paper analyzes the behavior of the X5CrNiMo17-12-2 steel plate during the deep drawing process. Mechanical and chemical properties obtained by spectrometry and standard tensile test are presented. The paper examines the basic calculation that gives good approximation of expected behavior during modeling of input specimen into final product. Based on the mechanical properties, simulation of material behavior was performed by using the method of finite elements in the ABAQUS software. The calculation results of the tool geometry mathematical model depending on steel plate behavior and simulations were compared
Models of evidence in function to reduce injuries of firefighters
Djelatnost profesionalnih vatrogasnih postrojbi je od posebnog javnog interesa te se ukazuje potreba za organizirani pristup, kako u spašavanju osoba i imovine te zaštiti zdravlja i sigurnosti vatrogasaca, tako i u očuvanju operativne sposobnosti vatrogasnih postrojbi.
Radi zaštite zdravlja i sigurnosti vatrogasaca potrebno je za izgradnju tehničko- tehnološke sposobnosti te organizaciju i edukaciju vatrogasaca primjenjivati pravila zaštite na radu koja propisuje Zakon o zaštiti na radu čime se razina rizika u aktivnostima vatrogasnih postrojbi smanjuje na najmanje moguću mjeru. Pravilnik o poslovima s posebnim uvjetima rada NN br. 5/84 od 14. veljače 1984. godine propisuje poslove s posebnim uvjetima rada i posebne uvjete koje moraju ispunjavati radnici za obavljanje tih poslova. U članku 3. su nabrojani poslovi s posebnim uvjetima rada, a pod točkom 14 su navedeni i poslovi vatrogasaca. Temeljem Zakona o zaštiti na radu sukladno članku 13. Pravilnika o izradi procjene opasnosti (N.N. br. 48/97, 114/02 i 126/03.) potrebno je izraditi procjenu opasnosti radnih mjesta u vatrogasnoj postrojbi. Procjenom opasnosti obrađuju su sljedeća područja: realizacija Plana za smanjenje razine opasnosti, revizija opasnosti u radnom prostoru, mjesta rada i radnih operacija, analiza radnih mjesta po grupama opasnosti, procjena preventivnih postupaka u društvu (osnovna i posebna pravila zaštite), analiza ozljeda na radu, plan mjera za smanjenje razine opasnosti, zaključak. Primjena pravila zaštite na radu je vrlo važna, ali na žalost nije dovoljna. Vatrogasci su izloženi mnogim rizicima na vatrogasnim intervencijama pa primjena pravila zaštite na radu, osobnih zaštitnih sredstava i opreme te ispravnost iste, nije uvijek garancija da neće doći do ozljede na radu. Radi toga je vrlo važno i pravilno evidentirati vatrogasne intervencije i evidencije eventualnih ozljeda na radu. Navedena evidencija bi bila velika pomoć kod budućih otklanjanja mogućih pogrešaka, ali i kao potpora društvenoj skrbi za vatrogasne djelatnike. Uvidom u bazu podatka koja se nalazi dijelom u evidencijama Ministarstva unutarnjih poslova, a dijelom u evidencijama Državne uprave za zaštitu i spašavanje, izgledno je da nedostaju podaci o sudionicima na intervencijama, ozljedama vatrogasaca na intervencijama, težina ozljeda kao i ozljede vatrogasaca sa smrtnom posljedicom. Zbog toga je potrebno izvršiti ponovno oblikovanje, suštinsko i formalno, postojećih evidencija, tj. tablica u koje bi se uvrstili svi potrebni podaci koji bi olakšali i sam postupak kod prijava ozljeda na radu te priznavanja profesionalnih oboljenja. Također, poboljšala bi se i preglednost stanja te učestalost ponavljanja određene vrste ozljeda. Svi ti podaci nalazili bi se u jednoj tablici. Takva upotpunjena evidencija bolje bi prikazala rizike na vatrogasnim intervencijama što bi rezultiralo kvalitetnijom procjenom opasnosti radnih mjesta, a time i bolji opis poslova vatrogasaca, rizika kojima su izloženi na radu te u konačnici i kvalitetniji plan mjera za smanjenje rizika.Professional fire departments is of special public interest and there is a need for an organized approach to the rescue of people and property and protecting the health and safety of firefighters, and the preservation of the operational capability of fire brigades. To protect the health and safety of firefighters necessary to build technical and technological capabilities, organization and training of firefighters to apply safety rules specified by the Law on Occupational Safety, and therefore the level of risk in the activities of fire departments is reduced to a minimum. Ordinance on jobs with special conditions Official Gazette 5/84 of 14.02.1984. The prescribed duties with special conditions and specific conditions that must be met by workers performing these tasks. In Article 3 are listed jobs with special conditions under section 14 are listed jobs firefighters. Pursuant to the law on health and safety in accordance with Article 13 Regulations on risk assessment (Official Gazette no. 48/97, 114/02 and 126/03.) Is necessary to make a risk assessment of jobs at the fire department. A risk assessment process the following areas: implementation of the Plan to reduce the level of risk, audit risk in the workplace, workplaces and work operations, analysis of jobs at risk groups, evaluation of preventive procedures in society (basic and special rules of protection), the analysis of work-related injuries , plan of measures to reduce the level of hazard conclusion. Application of the rules of safety at work is very important but unfortunately not enough. Firefighters are exposed to many risks on fire interventions, and application of the rules of occupational safety, personal protective equipment and devices, and the correctness of the same, is not always a guarantee that there will not be hurt at work. Therefore, it is very important to properly record the fire intervention and records of any injuries. Such records would be a great help in the future to eliminate possible errors, as well as support for social welfare to fire workers. Insight into the database, which is part of the records of the Ministry of the Interior, and partly in the records of the National Protection and Rescue Directorate, it is likely that data on participants in the intervention, and injuries to firefighters interventions, the weight of injuries and injury-related deaths of firefighters.
Therefore, it is necessary to perform re-formatting, and formally, existing records, or tables in which the data included all the needy and to facilitate the procedure for registration of occupational injuries and recognition of occupational diseases. Would improve the visibility of the state as well as the recurrence certain types of injuries. All information should be contained in a single table. Such completed records to reflect better the risks to fire interventions that would result in higher quality hazard assessment jobs and thus a better description of firefighters, the risks to which they are exposed to at work and ultimately better plan of measures to reduce risk
Assessment of workplace hazards of firefighters – the shortcomings of existing legislation, remarks and suggestions for alterations, based on scientific evidences
Posao vatrogasca karakterizira izloženost svim vidovima fizičke, kemijske i biološke ugroženosti života i zdravlja. Vatrogasci obavljaju poslove struke najvećim dijelom u mirnodopskom razdoblju, ali jednako tako su aktivni i u intervencijama prouzročenim ratnim djelovanjima. Moderan način života zahtijeva i upotrebu novijih vrsta kemikalija, novih materijala s različitim svojstvima i ponašanjem u procesu gorenja, te upotrebu novih tehnologija, pa je veoma teško predvidjeti i planirati sve vrste intervencija. Kao posljedica izazvanog, neposrednog i kratkotrajnog (mehaničkim, fizikalnim, kemijskim djelovanjem) ili naglog promijenjenog položaja i iznenadnog opterećenja tijela nastaje ozljeda. Težina ozljeda se određuje u odnosu na nekoliko faktora: opasnost po život, oštećenje organa, funkciju organa i radnu sposobnost. U skladu s tim dolazi do razvoja profesionalne bolesti koja je uzrokovana dugotrajnim i neposrednim utjecajem radnih uvjeta na zdravlje. Međutim, za primanje u ovu odgovornu i vrlo napornu službu kandidat mora ispunjavati više uvjeta, a između ostalog da je utvrđena njegova zdravstvena psihofizička sposobnost za poslove vatrogasca temeljem specijalističkog zdravstvenog pregleda na medicini rada koji je u skladu Pravilnikom o poslovima s posebnim uvjetima rada (NN 5/84), članak 3, točka 14. Prema Pravilniku vatrogasci se šalju na redovite liječničke preglede u vremenskom razdoblju od 24 mjeseca. No, uvidom i praćenjem obrađenih liječničkih nalaza evidentno je da kao posljedica rada u vatrogasnoj službi dolazi do raznih oštećenja i narušavanja zdravstvenog stanja i radne sposobnosti vatrogasaca. Jedan od čimbenika njihove radne sredine koji je veoma malo istražen u poslovima vatrogasaca, a dokazano liječničkim pregledima negativno djeluje na njihovo zdravlje i radnu sposobnost - je visokofrekventna buka. Štetno djelovanje buke na vatrogasce do sada nije istraživano iako postoje indicije i dokazi da je ona prisutna i štetno djeluje na zdravlje vatrogasaca. Izloženost vatrogasaca buci je u stalnom porastu jer raste broj vatrogasnih intervencija. Pri dizajniranju vatrogasnih sprava i vozila, kao i osobnih zaštitnih sredstava, nije primijećen značajniji pomak u iznalaženju kvalitetnijih rješenja koja bi smanjivala proizvodnju buke ili njen štetan učinak na zdravlje vatrogasaca. Analizirajući poslove vatrogasaca i njihovu radnu okolinu dolazi se do činjenice da buka kao jedan od faktora narušavanja zdravlja postoji, te da ona pri određenim situacijama prelazi dozvoljene razine. Stoga, kroz istraživanje uvjeta rada vatrogasaca, odnosno iznalaženje optimalnih materijala i opreme koja se koristi u vatrogastvu i koja će u odnosu na buku dovesti do postupnih smanjenja ili potpunog eliminiranja buke, rizik od profesionalnih oboljenja organa sluha svodi se na najmanju moguću razinu. Posljedično rezultatima znanstvenih istraživanja nameće se potreba da se Zakonskom legislativom odredi i propiše obvezno korištenje, kako osobnih zaštitnih sredstava za pojedinog vatrogasca na intervencijama, tako i da se u samom dizajnu opreme i vozila ide ka rješenjima koja bi emisiju buke smanjila na dopuštenu razinu. Osim toga, nameće se potreba promjene Pravilnika o poslovima s posebnim uvjetima rada (NN 5/84) prije svega zbog definiranja složenosti i kvalitete pregleda vatrogasca. Dakle, Pravilnikom bi trebalo odrediti da se vatrogascu sluh pregleda svakih godinu dana, a ne samo onda kada to struka/poslodavac traži. Ukoliko se kroz postojeće znanstvene indicije, ali i dokaze, problem svjesnog uništavanja sluha kod vatrogasaca kojima su izloženi kroz dugogodišnji rad bude zanemarivao, struka će imati velikih problema s kroničnim i ireverzibilnim posljedicama na zdravlje vatrogasaca.The work of firefighters is characterized in exposure to all forms of physical, chemical and biological threat of life and health. Firefighters perform profession duties in peacetime for most but are also active in interventions caused by war period. A modern way of life requires the use of newer type of chemicals, newer materials with different properties, the behavior in the process of burning and the use of new technology, so it is very difficult to predict and plan all kinds of interventions. As a result of induced, immediate, short-term (mechanical, physical, chemical action) or a sudden changed position and an unexpected load of the body also, the injury to the body is caused. Weight injury is determined in relation to several factors: the risk to life, damage to the organs, organs function and working ability. In line with this development comes to an occupational disease that is caused by long-term and direct influence of working conditions on health. However, for admission to this highly responsable and arduous office, the candidate must fulfill several conditions, among others things that his health is determined by pshycophysical ability for the firefighter jobs based on the specialist medical examination at the medical work in accordance with the Regulations on jobsrequiring special working conditions (Official 5/84), article 3, item 14. According to the Regulations, the firefighters are sent to regular medical examinations in a period of 24 months. Nevertheless, with inspection and monitoring of processed medical reports it is evident that as a consequence of the fire department work can lead to a variety of damage and disruption of health status and work ability of firefighters. One of the factors of their working enviroment, which is not much explored, and medical examinations prove the negative impact on their health and working ability, is the high frequency noise. Harmful effects of the noise on firefighters have not been investigated, althought there are indications and evidence that it is present and adversely affects the health of firefighters. Noise exposure of firefighters is increasing because of the growing number of fire intervention. When designing firefighter equipment and vehicles as well as personal protective equipment was not seen significant progress in finding better solutions todecreasing the production of noise and its detrimental effect on the health of firefighters. Analyzing the work of firefighters and their work environment leads to the fact that the noise exists as a factor in the decline of health and that in certain situations it exceeds the permitted level. Therefore, through study of working conditions of firefighters, apropos finding the optimum materials and equipment used in firefighting, which will in relation to noise, lead to a gradual reduction or complete elimination of noise, the risk of occupational diseases of the organs of hearing is reduced to the lowest possible level. Consequently the results of the scientific research a need is imposed, with the statutory legislation, to determine and prescribe the mandatory use of personal protective equipment for each firefighter on interventions and also that the design of equipment and vehicles moves toward solutions that would reduce the emission of noise to the allowed level. In addition, there is a need to change the Regulations on jobsrequiring special working conditions (Official 5/84) primarily due to defining the complexity and quality of the firefighters inspection. Thus, it should be determined by Regulations that the firefighter hearing is examined annually and not only when the profession/employer requires. If through the existing scientific indications, but evidences also, the problem of conscious destruction of hearing at which firefighters are exposed throughout years of service continues to be neglected, the profession will have considerable problems with chronical and irreversible consequences on the health of firefighters
SELECTION OF TOOL GEOMETRY IN REGARD TO MATERIAL BEHAVIOR DURING DEFORMATION PROCESS
U ovome istraživanju analizira se ponašanje lima X5CrNiMo17-12-2 tijekom procesa dubokog izvlačenja. Prikazana su mehanička i kemijska svojstva ispitivanog lima dobivena pomoću spektrometrije i standardnog vlačnog testa. U radu je ispitan osnovni proračun koji daje dobru pretpostavku očekivanog ponašanja materijala prilikom oblikovanja ulaznog uzorka u konačni oblik. Na temelju mehaničkih svojstava izvedena je simulacija ponašanja materijala metodom konačnih elemenata u softveru ABAQUS. Rezultati proračuna matematičkog modela alatne geometrije u ovisnosti o ponašanju materijala i simulacije su uspoređeni.This paper analyzes the behavior of the X5CrNiMo17-12-2 steel plate during the deep drawing process. Mechanical and chemical properties obtained by spectrometry and standard tensile test are presented. The paper examines the basic calculation that gives good approximation of expected behavior during modeling of input specimen into final product. Based on the mechanical properties, simulation of material behavior was performed by using the method of finite elements in the ABAQUS software. The calculation results of the tool geometry mathematical model depending on steel plate behavior and simulations were compared
CALCULATION AND PARAMETER SELECTION FOR CONVEYOR BELT
U ovome radu prikazan je proračun transportne trake za kontinuirani prekrcaj robe. Odabran je materijal ugljena prašina, te duljina transportne trake od 300 metara uz promjenu visine od 10°. Zadan je učin od 150 tona satnog kapaciteta, proračunati svi potrebni funkcionalni dijelovi prema standardima te konačan rezultirajući učin. Prikazan je postupak odabira brzine transportne trake, širine trake, proračun pogonske snage, odabir dimenzija pogonskog bubnja i nosivih valjaka. Korišten je standardni model proračuna. Sile koje se javljaju u procesu su proračunate te je korištena metoda kontrole proračuna obilaskom po konturi.This paper presents the calculation for conveyor belt for continuous transportation of material. The investigated conveyor is designed for transportation of coal dust, the selected length of the conveyor belt being 300 meters with the rising angle of 10°. The required carrying capacity was 150 tons per hour. All necessary functional components of the conveyor belt were calculated according to the standards, as well as the desired final output. The paper describes the process of selecting conveyor belt speed, belt width, the calculation of operating power, the choice of dimensions of the drive drum and bearing rollers. The standard model for belt conveyor calculation was used. The forces occurring in the process were investigated and the method of force contour calculation was used for control
Statistical analysis and grade of occupational injuries in the Republic of Croatia
Temeljni cilj ovoga rada jest istražiti stanje sigurnosti na radu u Republici Hrvatskoj. Ukupan broj ozljeda na radu i broj smrtno stradalih na radu predmetom se analize pomoću metode deskriptivne statistike za razdoblje od 1996. do 2016. godine. Posebna pozornost posvećuje se istraživanju korelacije između broja ozljeda na radu, broja smrtno stradalih i kretanja bruto domaćeg proizvoda, ukupne zaposlenosti i zaposlenosti po pojedinim gospodarskim djelatnostima. Dobiveni rezultati istraživanja omogućit će sagledavanje osnovnih trendova sigurnosti na radu u Republici Hrvatskoj te detektiranje onih gospodarskih grana u kojima kretanje zaposlenosti determinira ukupan broj ozljeda na radu. Rezultati istraživanja temelje se na metodama deskriptivne statistike i statističkoj metodi korelacijske analize.The basic objective of this paper is to investigate the state of work safety in the Republic of Croatia. The total number of injuries at work and the number of fatalities at work were analyzed using the method of descriptive statistics for the period 1996 - 2016. Special attention is paid to the correlation between the number of injuries at work, the number of fatalities and the movement of gross domestic product, total employment and employment by individual economic activities. The results of the research will provide an overview of the basic labor safety trends in the Republic of Croatia and the identification of those industries in which employment trends determine the total number of injuries at work. The results of the research are based on the methods of descriptive statistics and the statistical method of correlation analysis
Tactic application of system for obtaining compressed foam
CAFS je sustav za gašenje komprimiranom pjenom (Compressed Air Foam System) koji omogućuje aktivno i preventivno gašenje požara, a pogodan je kada požar poprima obilježja nekoliko vrsta požara. Zahvaljujući mogućnosti finoga doziranja vlažnosti pjene, višestruko se povećava učinkovitost samo jednoga spremnika vode na vatrogasnom vozilu. Ova karakteristika dolazi do izražaja poglavito u sredinama s ograničenim količinama vode. Dobro prianjanje na površine svih vrsta čini komprimiranu pjenu izuzetno dobrim sredstvom za gašenje i prevenciju širenja požara klase “A”. Osim za požare klase “A”, komprimirana pjena dobro je sredstvo za gašenje i požara klase “B”.In accordance with increasing technological innovations in operational work, necessarily comes to changing of operational-tactical procedures depending on the type of intervention. Main goal is to enable better fire protection by the use of newly developed and available equipment and extinguishing agents. In 2002. the CAFS system for fire compressed foam (Compressed Air Foam System) was introduced in Croatia. The system allows active and preventive fire extinguishing, suitable when a fire takes on the characteristics of several types of fire. Thanks to the fine dosing of humidity foam, increase of efficiency is obtained by the use of only one tank of water on the fire trucks. This characteristic comes to the fore especially in areas with limited amounts of water. Furthermore, the quality of the foam is several times improved compared to the foam obtained in a classical method. Good adhesion to surfaces of all kinds makes compressed foam an extremely good mean of preventing spread of fire class “A “. Compressed foam can also be used as a good extinguishing agent for fire class “B “. There are some limitations with regard to the capacity CAFS is significantly lower compared to the possibilities of classical foam system. However better insight in foam system capabilities offers new operational-tactical procedures for fire extinguishing
Firefighting protection for LNG terminals
U ovom radu prikazana je protupožarna zaštita kod LNG terminala. Za uspostavljanje takve zaštite prvenstveno je ključno poznavanje svojstava LNG-a, koja mogu varirati u ovisnosti o njegovom porijeklu. Zbog boljeg i lakšeg razumijevanja problematike, daje se i kratki opis lanca opskrbe LNG-em, a navodi se i razlog njegovog ukapljivanja s naglaskom na njegove izvanredne ekološke, ekonomske i energetske prednosti. Opisuju se i opasni fenomeni koji uključuju bukteći požar, požar lokve, požar mlaza, eksplozije, gušenje, ali opasnosti koje su povezane sa samom kriogenom temperaturom LNG-a. Tu je važno naglasiti da sve ove opasnosti neće predstavljati visok rizik ukoliko se smanje posljedice ili vjerojatnost njihove pojave. Opisuje se i zaštita od požara na ovakvim terminalima koja uključuje sigurnosne sustave kao što je ESD sustav, detekcija požara, ispuštanja i izlijevanja, sustavi za zaštitu od požara i gašenje vodom, druga oprema za gašenje i kontrolu požara, te mjere i oprema za zaštitu osoba.This paper presents aspects of firefighting protection for LNG terminals. For establishing such protection it is primarily important to know the characteristics of the LNG, which can vary depending on its origin. For easier and better understanding of the relevant problem area, a short description of the LNG supply chain is also given, accompanied by giving the reasons for its liquefying, with emphasis on its extraordinary ecological, economic, and energy advantages.
Certain dangerous occurrences are described such as flash fires, pool fires, jet fires, explosions, and suffocation, as well as some dangers connected with the cryogen LNG temperature.
It is important to emphasize that all of these dangers will not pose a high risk if the consequences or the probability of their occurrence are reduced. The paper also describes the firefighting protection at this kind of terminal, which includes safety systems such as ESD systems, fire detection, discharge and outflow, firefighting systems and water extinguishment, other equipment for firefighting and fire control, as well as personal safety measures and personal protective equipment
Transport of Gasoline by Road and Extinguishing Tactics
U radu je provedeno istraživanje transporta cisterne pri prijevozu opasne tvari s fokusom na opasnost od prevrtanja, te taktički pristup gašenju požara takvog incidenta. Kao ključan dokument u prijevozu opasnih tvari cestom, sporazum ADR je konzultiran uz analizu vijeka trajanja vozila za transport u Republici Hrvatskoj. Analizirani su glavni uzroci nepravilnosti na tehničkim pregledima vozila za prijevoz opasnih tvari. Prikazana je i procedura koja se obavlja pri prijevozu opasnog tereta - benzina na Hrvatskim autocestama uz pomoć karti rizika, odabira sigurnih ruta. Temeljem odabranog prijevoza opasne tvari dane preporuke za vatrogasnu taktiku u slučaju incidenta.The paper investigates the transport of tanks during the transport of dangerous goods with a focus on the danger of overturning, and a tactical fire extinguishing approach to such an incident. As a key document in the transportation of dangerous goods by road, the ADR agreement was consulted with the analysis of the service life of transport vehicles in the Republic of Croatia. The main causes of irregularities in the technical inspections of vehicles for the transport of dangerous goods were analyzed. The procedure performed when transporting dangerous goods - gasoline on Croatian motorways with the help of risk maps, selection of safe routes is presented. Based on the selected transport of dangerous goods, recommendations for firefighting tactics in case of an incident were given
Transport of Gasoline by Road and Extinguishing Tactics
U radu je provedeno istraživanje transporta cisterne pri prijevozu opasne tvari s fokusom na opasnost od prevrtanja, te taktički pristup gašenju požara takvog incidenta. Kao ključan dokument u prijevozu opasnih tvari cestom, sporazum ADR je konzultiran uz analizu vijeka trajanja vozila za transport u Republici Hrvatskoj. Analizirani su glavni uzroci nepravilnosti na tehničkim pregledima vozila za prijevoz opasnih tvari. Prikazana je i procedura koja se obavlja pri prijevozu opasnog tereta - benzina na Hrvatskim autocestama uz pomoć karti rizika, odabira sigurnih ruta. Temeljem odabranog prijevoza opasne tvari dane preporuke za vatrogasnu taktiku u slučaju incidenta.The paper investigates the transport of tanks during the transport of dangerous goods with a focus on the danger of overturning, and a tactical fire extinguishing approach to such an incident. As a key document in the transportation of dangerous goods by road, the ADR agreement was consulted with the analysis of the service life of transport vehicles in the Republic of Croatia. The main causes of irregularities in the technical inspections of vehicles for the transport of dangerous goods were analyzed. The procedure performed when transporting dangerous goods - gasoline on Croatian motorways with the help of risk maps, selection of safe routes is presented. Based on the selected transport of dangerous goods, recommendations for firefighting tactics in case of an incident were given