Safety Enclosure Research Articles

Анализ нормативного метода оценки доли перелившейся через ограждение жидкости при квазимгновенном разрушении резервуара

Purpose. When assessing fire risks at oil and petroleum product storage facilities, it is necessary, alongside, to consider the scenario of a liquid spill in case of quasi-explosive tank destruction. The breakthrough wave formed in this case is able to overflow through safety enclosure. The normative method allows assessing the proportion of overflowing liquid only through the enclosure in the form of vertical protective walls, while earth dikes of trapezoidal shape with different slope angles have become most widespread at the specified objects of protection. The article justifies the relevance of continuing the research on assessing the proportion of liquid overflowing through enclosures of various geometric shapes in case of quasi-explosive destruction of the tank. Methods. Statistical data analysis methods on actual quasi-explosive tank failures at production facilities in Russia and abroad have been used, including a full-scale experiment on the destruction of VST-700 with water, as well as observations, comparisons, descriptions, and generalizations. Findings. It is shown that the definition of the term quasi-explosive tank failure requires additions and clarifications based on statistical data analysis on the destruction of vertical steel tanks. The mechanism for opening the wall of a vertical steel tank has been clarified, which leads to the occurrence of a breakthrough wave, and its characteristics has been given. The application limitations of the existing method for estimating the proportion of overflowing liquid only through the enclosures in the form of vertical protective walls have been justified. Research application field. The results of the study can be used for developing the tenets of the method for determining fire risk design values at production facilities when considering a scenario related to a liquid spill in case of quasi-explosive destruction of a vertical steel tank. Conclusions. Based on the analysis results of the tenets of the method under consideration, the necessity to continue studies aimed at assessing the proportion of liquid overflowing through enclosures of various geometrical shapes during tank destruction, the value of which is needed for quantitative assessment of fire risks at production facilities, has been justified.

Design of a containment apparatus for synchrotron XAS measurements of radioactive fluid samples under high temperatures and pressures.

The simple working principles and versatility of the hydrothermal diamond-anvil cell (HDAC) make it highly useful for synchrotron x-ray studies of aqueous and fluid samples at high pressure-temperature (P-T) conditions. However, safety concerns need to be overcome in order to use the HDAC for synchrotron studies of aqueous radioactive samples at high temperatures and pressures. For accomplishment of such hydrothermal experiments of radioactive materials at synchrotron beamlines, the samples are required to be enclosed in a containment system employing three independent layers of airtight sealing at some synchrotron facilities while enabling access to the sample using several experimental probes, including incoming and outgoing x-rays. In this article, we report the design and implementation of a complete radiological safety enclosure system for an HDAC specialized for high P-T x-ray absorption spectroscopy (XAS) measurements of aqueous solutions containing the actinides at synchrotron beamlines. The enclosure system was successfully tested for XAS experiments using the HDAC with aqueous samples containing depleted uranium at temperatures ranging from 25 to 500 °C and pressures ranging from vapor pressure to 350 MPa.

Containment system for experiments on radioactive and other hazardous materials in a Paris-Edinburgh press.

Recent technical developments using the large volume Paris-Edinburgh press platform have enabled x-ray synchrotron studies at high pressure and temperature conditions. However, its application to some materials of interest, such as high hazard materials that require special handling due to safety issues, reactivity, or other challenges, has not been feasible without the introduction of special containment systems to eliminate the hazards. However, introduction of a containment system is challenging due to the requirement to provide full safety containment for operation in the variety of environments available, while not hindering any of the experimental probes that are available for inert sample measurement. In this work, we report on the development and implementation of a full safety enclosure for a Paris-Edinburgh type press. During the initial development and subsequent application stage of work, experiments were performed on both cerium dioxide (CeO2) and uranium (U). This device allows for full implementation of all currently available experimental probes involving the Paris-Edinburgh press at the High Pressure Collaborative Access Team sector of the Advanced Photon Source.

Second generation laser-heated microfurnace for the preparation of microgram-sized graphite samples

We present construction details and test results for two second-generation laser-heated microfurnaces (LHF-II) used to prepare graphite samples for Accelerator Mass Spectrometry (AMS) at ANSTO. Based on systematic studies aimed at optimising the performance of our prototype laser-heated microfurnace (LHF-I) (Smith et al., 2007 [1]; Smith et al., 2010 [2,3]; Yang et al., 2014 [4]), we have designed the LHF-II to have the following features: (i) it has a small reactor volume of 0.25mL allowing us to completely graphitise carbon dioxide samples containing as little as 2μg of C, (ii) it can operate over a large pressure range (0–3bar) and so has the capacity to graphitise CO2 samples containing up to 100μg of C; (iii) it is compact, with three valves integrated into the microfurnace body, (iv) it is compatible with our new miniaturised conventional graphitisation furnaces (MCF), also designed for small samples, and shares a common vacuum system. Early tests have shown that the extraneous carbon added during graphitisation in each LHF-II is of the order of 0.05μg, assuming 100pMC activity, similar to that of the prototype unit.We use a ‘budget’ fibre packaged array for the diode laser with custom built focusing optics. The use of a new infrared (IR) thermometer with a short focal length has allowed us to decrease the height of the light-proof safety enclosure. These innovations have produced a cheaper and more compact device. As with the LHF-I, feedback control of the catalyst temperature and logging of the reaction parameters is managed by a LabVIEW interface.

Dynamic Thermal Modeling of MV/LV Prefabricated Substations

With the expansion and infilling of urban areas, the demand for electric power is driving the design and capacity of distribution substations to their thermal limits. Distribution transformer substations are increasingly required to be compact, reliable, safe, and intelligent. To efficiently utilize city space and to support the intermittent load flows imposed by smart-grid features, such as distributed generation, the transformers are expected to operate close to or occasionally over their ratings, with stalled or little air circulation inside the safety enclosure. Dynamic thermal models with physically validated convection and radiation heat-transfer components are essential for the real-time thermal rating of substations. Natural convection via the air inside the cabin to the outside ambient air plays the major role in cooling down a transformer. In this study a scale model of a prefabricated substation is examined to draft a numerical solution which is based on stack ventilation principles. A clear and expandable first principle approach is used to quantify heat transfer through ventilation openings. Measurements from actual cabins and 3-D finite element method simulations are used to validate the numerical model.

Modular Automation Platforms: A Case Study of a Flexible NMR Sample Preparation Robot

A variety of features used by our Department in the design and integration of Automation Platforms are presented here. A challenging project for any automation group is the automation of NMR sample preparation. The dispensing of highly volatile or viscous solutions into the typical 5 mm ID NMR glass tube, and the subsequent capping of the tube, presents unique problems. An angled incremental single-channel dispensing technique prevents bubble formation when a 10-mM protein—based solute is used. A novel gripper finger design, used in conjunction with in-house fabricated Teflon caps, allows reliable capping of NMR tubes. In situ vortexing minimizes vial handling with increased throughput. Magnetic mounting of robot tools (hands) provides precise snap-in positioning with collision-safe breakaway. This simplifies crash recovery during development testing and production use. A wraparound Safety Enclosure with modular safety circuit fulfills ANSI/RIA R15.06–1999 Safety Requirements. Flexible control software permits run interruption for loading and preparation of additional NMR tubes. Prepared samples may be removed during run interruption. A “Fly-By” barcode scanning tool enables positive compound sample ID with improved throughput. Preexisting instrument control software is conveniently interfaced to a Scheduler application through an open-architecture instrument integration framework. This framework allows the development of automation platform—independent Middleware for schedule and assay portability. A new generation of low-power, lightweight, portable and expandable platforms is also presented where a building block tandem approach is used in conjunction with the Rent-a-robot concept for robot recycling.

Semper develops new safety enclosure for post-room workers

Semper develops new safety enclosure for post-room workers

Carbon impurity characterization on a linear plasma device using visible emission spectroscopy

Visible emission spectroscopy is used to quantify the carbon impurity concentration in the linear plasma divertor simulator of the Plasma Interaction Surface Component Experimental Station (PISCES-B). A technique has been developed to obtain noninvasively the absolute photometric calibration of a visible spectrometer in order to minimize exposure of equipment in the beryllium safety enclosure of PISCES-B. The principal intrinsic source of carbon appears to be chemical sputtering at the vessel walls, with a typical background concentration ∼0.2% with deuterium plasmas. Helium plasmas have a lower carbon contamination ∼0.01%. Methane gas injection is used to increase the carbon contamination in a controlled manner to better simulate tokamak edge plasma conditions. It is found that the spectroscopic method of determining the carbon fraction agrees well with the relative gaseous carbon contamination measured with a residual gas analyzer during plasma operations.

Some considerations to the failure analysis of a pointwise attached steel liner membrane under constraint load

In the application of reinforced or prestressed concrete reactor containments, the safety enclosure will be obtained through a steel liner membrane, which is attached pointwise to the interior concrete surface. It is the objective and aim of this study to analyse the overall structural behavior of the bonded system consisting of concrete containment, studs, and steel liner—especially under the aspect of extreme load and deformation conditions. The parametric analysis is carried out on the basis of the geometric length/depth ratio l t = 12 of a single liner field. In order to reduce the considerable computational effort to a minimum, it is necessary to decouple the overall system in its structural components, i.e., at first an imperfect predeflected ‘buckling’ field and the residual ‘plane’ liner field are considered separately. A further reduction enablesm the use of stud anchor characteristics which are based on experiments. Three-dimensional analyses are performed for the single ‘buckling’ field to obtain specific load-displacement functions; the residual plane system is considered with two- as well as one-dimensional models. For the comprehensive parametric evaluation of the overall system behaviour, a linear model is assumed to which these load-displacement functions are applied. Constraint temperatures are introduced as a unit scale—up to failure of the overall system; hereby partial structural failure might lead to temporary relief.

Safety enclosure for mercury filled McLeod Gauge.

The enclosure presented both protects the gauge and contains the mercury if breakage should occur.

Penitenciaría federal de Marion. Illinois (U. S. A.)

This federal prison is designed to house 600 prisioners, and has been planned so that it can be easily enlarged, to accommodate 1,000 inmates. The distribution is radial, and entry is via an administrative building, which lies outside the double metallic safety enclosure. A main corridor leads to the central nucleus, from which three other corridors branch off. The one on the right connects with five units, containing the cells, a general dormitory, the library, public hall, gymnasium and a school. The central corridor leads to further cell units, the admission office, hospital and secondary services, whilst the left hand corridor provides access to the chapel, the prisoners dining mess, kitchens and washing rooms. The building is of high quality and has a noble aspect, following modern trend in this type of constructions.

Safety Closure Caps

To the Editor:— I am writing in defense of safety closure caps, as a reply to Dr. W. M. Schmidt's letter inThe Journal(180:1144 [June 30] 1962). With over 4 million babies born each year and with miniature drug stores in every home, drug poisoning in children, can soon become a colossal and even more tragic problem in a few short years. I should like to see a safety enclosure of some type (not necessarily the one in my published report) placed on all bottled medications, proprietary and nonproprietary, and on all household products with toxic chemicals as well. Over one-third of the poison fatalities in children are due to drugs, and the incidence runs a good bit higher—over 50% Safety caps are not fool-proof by any means. Children will at times circumvent any and all precautionary measures. Yet, for each child successful in removing the cap, there