Road Tankers Research Articles

ALCOA ALLOY 5182 RTSG1

Abstract Alcoa has developed this special grade of alloy 5182 for construction of road tankers. This datasheet provides information on composition, physical properties, elasticity, tensile properties, and bend strength. It also includes information on corrosion resistance as well as forming and joining. Filing Code: Al-441. Producer or source: Alcoa European Mill Products, Switzerland.

Injection of CO2 at Ambient Temperature Conditions – Pressure and Temperature Results of the “cold injection” Experiment at the Ketzin Pilot Site

Abstract From June 2008 to August 2013, slightly more than 67 kt of CO2 were injected at the Ketzin pilot site (Brandenburg, Germany). The CO2 reservoir is a saline aquifer at a depth of 630 – 650 m with initial pressure and temperature conditions of about 33 °C/62 bar. These reservoir conditions are near the critical point of pure CO2 (31.0 °C/73.8 bar) and the CO2 liquid-vapour equilibrium. In order to avoid phase transitions and near-critical phenomena throughout the injection process the CO2, which was delivered by road tankers and stored in intermediate storage tanks on site at ∼ -18 °C/21 bar, was pre-conditioned at site and pressurised to ∼ 65 bar and heated to ∼ 40 °C during regular operation. This injection process design worked exceptionally well. However, such a pre-conditioning and heating of the injected CO2 to elevated temperature is unrealistic for an industrial sized CO2 storage setting as the energy need is high and costly and the CO2 will be delivered by pipeline already at ambient temperature. To study the effects of lower pre-conditioning temperature and effects of potential two-phase flow on the injection process, a “cold injection” experiment was carried out between March and July 2013. The injection wellhead temperature was decreased stepwise from 40 °C down to 10 °C. Below 20 °C two-phase flow developed in the surface installations and in the injection well down to the reservoir and a mixture of gaseous and liquid CO2 has been injected. This two-phase CO2 injection ran smoothly for eight weeks without any operational issues.

Road Haulage Constraints in the Transportation of Petroleum Products in Northern Nigeria

In Nigeria, about 80% of petroleum movements are done on the road and there has been a steady growth in number of road tanker vehicles. This study examines road haulage constraints in the transportation of petroleum products. The study relied on primary data obtained through systematic administration of questionnaire to truck drivers at the point of waiting to load petroleum products in Kaduna Refinery. In all, 182 respondents were sampled. These problems were rank-ordered, the result of the study reveals that the major constraint confronting tanker drivers in conveying petroleum products to the selected locations is delay at police and military check points (mean= 1.72), followed by mechanical problems (mean=2.17), using K-W non parametric test. Furthermore, the correlation matrix of the trucking problem result reveals that five pairs of the constraints were significant with the strongest positive correlation being that of bad roads and delay in offloading, r=0.81, p< 0.001. These results are fundamental for the prioritization of palliative measures to improve the constraints of road haulage of petroleum products in northern Nigeria.

Конструирование автомобильных танкеров с учетом осевой нагрузки и боковой устойчивости

Конструирование автомобильных танкеров с учетом осевой нагрузки и боковой устойчивости

Finite element simulation of road tanks for ADR and fatigue assessments

Purpose – The paper aims to illustrate the application of a state-of-the-art fatigue prediction concept (IIW recommendations) to the ADR calculation requirements, in order to include failure-critical weld details to the strength assessment of road tanks. The level of calculation accuracy and, therefore, safety of such structures transporting dangerous goods can be substantially increased. Design/methodology/approach – A case study of a 2-compartment aluminum alloy LBGF tank used for the transportation of gasoline/petroleum products is conducted adopting the meshing directives of the structural hot spot stress concept (SHSSC) of the IIW recommendations for the weld details of the structure. The stresses on the prescribed Hot Spots are extracted from the solutions of each load case described in the ADR legislation and assessed both in terms of static strength according to EN 14286 and fatigue strength using the standardized IIW assessment curves (FAT curves). Findings – The detailed analysis of the road tank has successfully allocated the failure critical points of the structure. Additionally it has illustrated the ability of the embedded fatigue concept to accurately calculate the stresses which can later be used for the durability evaluation, providing that at least some operational load spectra become available. Research limitations/implications – The use of a global meshing and calculation concept offers a relatively limited accuracy level considering any individual weld detail. On the other hand, it offers a sufficient overview of the whole structure with minimum effort and costs. Practical implications – Time-consuming integrity inspections of road tanks can be minimized, as the failure critical locations are identified and therefore easily monitored. Furthermore, the transformation of the fatigue life prediction issued by the proposed calculation into actual operational time may be used to determine realistic time intervals between service pauses required for the safe operation of such structures. Originality/value – The present study constitutes the first approach of embedding the SHSSC into the calculation of large-scale structures such as road tanks and verifies the applicability of this concept beyond simple geometries and load cases.

CFD analysis of the dispersion of toxic materials in road tunnels

The present work is aimed at analyzing the evolution of accidental scenarios deriving from the release of toxic materials inside a tunnel. This scenario, compared to the more frequently investigated cases of fire, followed by smoke dispersion, may involve a large variety of common products characterized by widely differing physical properties; nonetheless it has been analysed in the literature less than expected. The present study compares the dispersion of two common toxic chemicals (chlorine and ammonia), in order to derive some preliminary information about the influence of the physical properties and the release rate. A reference road tunnel geometry is assumed, while the release occurs from ground level, at the centre of one lane and in the middle of the tunnel. Two study cases involving a road tanker, transporting the product as liquefied gas under pressure, were considered: a catastrophic release, from a 220 mm hole, emptying the tanker in a few tens seconds (case A), and a continuous release, from a much smaller hole (15 mm), lasting 5 min (case B). For the sake of simplicity, the release is assumed to be in gaseous phase; the dispersion of the toxic is simulated for the 5 min period following the start of the release using a CFD (Computational Fluid Dynamics) analysis, according to an RANS (Reynolds-Averaged Navier–Stokes) approach with the standard k–ε turbulence model, assuming no ventilation conditions. Structured curvilinear grids with hexaedric cells, refined according to the local concentration gradient, are used. For case A scenarios, especially for the whole release duration, dispersion is mainly governed by the “plug-flow” effect caused by the large volume of toxic entering the tunnel in a rather short time; then, the role of diffusivity and gravity becomes more important. Chlorine, heavier than air and with lower diffusivity than ammonia, progressively accumulates towards the floor; the dispersion of ammonia, which is lighter than air, appears more influenced by diffusivity than by gravity, since a limited stratification is observed. These trends are more evident for case B scenarios, where the toxic flow rates are much lower. It is expected the results will give some useful insight into the dispersion phenomenon within highly confined spaces and maybe also provide some suggestion about ventilation systems design and emergency procedures.

A Methodology to Assess Road Tankers Rollover Trend During Turning

A Methodology to Assess Road Tankers Rollover Trend During Turning

Comparison of the stress distributions of liquid gas road tankers with various configurations during braking, cornering, and vertical bump maneuvers

This paper compares the stress and displacement distributions of different head-shell junction configurations in LPG road tankers during different vehicle design maneuvers, such as braking, cornering, and vertical bumps, for the first time. Various combinations of heads (e.g., spherical and toroidal) and shell cross sections (circular and elliptical) are considered. The ABAQUS finite element software is used to model and analyze the fluid-filled tankers. The results show that the most critical maneuver affecting the fluid-filled tankers is cornering and the safest maneuver is braking. Moreover, the results reveal that the outer surface of the tanker generally behaves the most critically in all maneuvers, and cylindrical tankers with smaller cross-sections behave more acceptably compared to those with larger cross-sections. Among fluid-filled vehicle tankers with identical platform areas, tankers with elliptical cross-sections behave the most acceptably.

Review on Design Optimization of Liquid Carrier Tanker for Reduction of Sloshing Effects

This Paper Reviews Briefly The Current Research On Sloshing And Its Effect In Liquid Carrier Tanker. The Aim Of This Paper To Study The Basics Of Sloshing And Its Prevention (Mainly In Liquid Carrier Tanker) The Liquid Sloshing Is Free Surface Fluctuation Of Liquid When Its Container Is Excited By External Vibrations Such As Earthquakes. The Liquid Sloshing May Cause Various Engineering Problem, For Example Instability Of Ships In Aero Engineering And Ocean Engineering, Failures On Structural Systems Of The Liquid Container. The Tanker Used For The Transportation Of Liquid Over The Road-Ways Is An Integral Part Of The Carrier/Vehicle. The Tanker Is Expected To Withstand The Unbalanced Forces On Account Of Transit Over Uneven And Irregular Surfaces/Contours Of The Road As Also Due To Sudden Acceleration Or Deceleration (Due To Application Of Brakes). Keywords-Sloshing, Impact, Baffle, Simulation Sloshing can be defined as dynamic load acting over a tank structure as a result of the motion of a fluid with free surface confined inside the tank. Liquid sloshing is a kind of wave motion inside a partially filled tank. The sloshing phenomenon is of great practical importance to the safety of the liquid transport. Under external excitations, with large amplitude or near the natural frequency of sloshing, the liquid inside a partially filled tank is in violent oscillations. In this paper we will see the background behind the sloshing phenomena to define the problem in proper manner. Also we will see the research work carried related to this problem, proposed methodology to go for solution and scope of work. The tanker used for the transportation of liquid over the road-ways is an integral part of the Carrier/ Vehicle. The tanker is expected to withstand the unbalanced forces on account of the transit over uneven and irregular surfaces/ contours of the road as also due to sudden acceleration or deceleration (due to application of brakes). As a result, `sloshing' of the liquid is experienced within the tanker. Different aspects of analyses are necessary to design the tanker but sloshing analysis is also one of the prominent aspects for reducing its detrimental effects over structure of tanker. Sloshing can be the result of external forces due to acceleration/deceleration of the containment body. Of particular concern is the pressure distribution on the wall of the container reservoir and its local temporal peaks that can reach as in road tankers twice the rigid load value. In road tankers, the free liquid surface may experience large excursions for even very small motions of the container leading to stability problems. Analysis of the sloshing motion of a contained liquid is of great practical importance. Motion of a fluid can persist beyond application of a direct load to the container; the inertial load exerted by the fluid is time-dependent and can be greater than the load exerted by a solid of the same mass. This makes analysis of sloshing especially important for transportation and storage tanks. Due to its dynamic nature, sloshing can strongly affect performance and behavior of transportation vehicles, especially tankers filled with oil. In fact, a significant amount of research has gone into developing numerical models for predicting fluid behavior under various loads. Hence liquid sloshing is a practical problem with regard to the safety of transportation systems, such as oil tankers on highways, liquid tank cars on railroads, oceangoing vessels with liquid cargo, propellant tank used in satellites and other spacecraft vehicles, and several others

Carrying Capacity of Horizontal Cylindrical Shells on Saddle Supports

The article is devoted to the influence of carrying capacity on the stability of laterally loaded cylindrical shells. The influence of initial imperfections on the stability of the laterally loaded shell is also taken into consideration. The investigated structure is a simplified variant of the case of cylindrical shell (road tank – for example Pascenko, 2009; Pascenko, Stejskal, 2008) located on two saddle supports. The initial shape imperfections are created by pushing the saddle support into the shell. The new deformed shape is used as an imperfect shell in the following nonlinear analysis of stability. The main objective of the analysis is to find the reduction factor α depending on the change of geometric parameters of the numerical model (embracing angle 2θ, wall thickness t). The shell deformation around the saddle support is also monitored. Numerical analysis is carried out by means of a computer program COSMOS/M based on the finite element method (FEM).

Dynamic Analysis of Behavior of Three-axle Semi-trailer Road Tank Going on Special Waved Roadway

This paper deals with the dynamic analysis of a truck with semi-trailer three-axle road tank for transport of loose materials like corn (barley, wheat, rye, oats, etc.). Firstly, the natural frequencies and mode shapes of truck-tank combination are calculated. Computer simulations of going on special waved road are performed for several speeds. Responses and maximum displacements are analyzed in vertical and lateral directions. These analyses represent a theoretical preparation of the experimental testing of the road tank. Obtained forces and reactions of these simulations may be used for the quasi-static analysis of deformation and stresses of the road tank. These results may also be used for extensive dynamic and fatigue analyses of the road tank and its behavior in real traffic conditions. Dynamic simulations of the simplified truck-tank model are carried out using software SIMULATION 2012 which is based on the finite element method (FEM).

Structural Integrity and Health Monitoring of Road and Railway Tanks based on Acoustic Emission

Structural Integrity and Health Monitoring of Road and Railway Tanks based on Acoustic Emission

Finite Element Analysis of In-Plane Displacements and Von-Mises Stresses in Ellipsoidal and Circular Cylinderical Petroleum Tankers

Road tankers are the most used means of transporting petroleum product to end users due to its cost effectiveness and energy-efficiency. The cylindrical tank has been well designed for by ASME VIII divisions 1 and 2 using analytical equations. Petrol tankers are not circular but elliptical probably for stability during transportation. This paper has used the finite element method to investigate in-plane displacements and Von-Mises stresses in both circular and elliptical cylindrical tanks under full loading. An elliptical OANDO? tanker of 66.78 m3volume and shell thickness of0.2 mmand an equivalent volume circular cylindrical tank was used for the simulation. MATLAB? was used to generate geometrical mesh model of the petroleum tankers, extract element coordinates and conduct the finite element analysis. Plane strain condition was used in analyzing a section of the petroleum tanker. It was observed that an equivalent volume circular cylindrical tank was under a higher internal pressure (16,858 N/m2) compared to the elliptical cylinder (14,480 N/m2). Von-Mises stress and in-plane displacements showed direct linear relationships with internal fluid pressure. Von-Mises stress in the elliptical tank was found to be lower (5.7 × 106 N/m2) than for the circular tank (8 × 106 N/m2). In plane displacements was zero in the longitudinal direction for both tanks and of the order of 10-4 mm in the y-direction for both tanks with the circular larger by about 2.5 × 10-3 cm. So in addition to tank stability on the lorry, the Von-Mises stresses were lower as well for the elliptical tank. It was also observed that Von-Mises stresses were far below the yield stress of the steel plate. However, the effect of weldment area on lowering of yield stress was not studied. Stress values were validated using analytical method and found to be insignificantly different (P > 0.05).

Thermal Radiation and Impact Assessment of the LNG BLEVE Fireball

Abstract Correlations are presented that represent consensus views on the influence of mass of LNG in the release on BLEVE fireball diameter, duration, and radiation output. And when the BLEVE fireball accidents of different load of LNG road tankers occurred, the corresponding safety distances of thermal radiation influence are calculate.

Transportation of Liquefied Gases: Assessing the Risk of Thermal Damage to Roadside Infrastructure from a Road Tank “Bleve”

An assessment of risk posed by a road transportation of liquefied gases to roadside property is considered. The attention is focussed on an estimation of the probability of thermal damage to a roadside object. Such damage can be caused by a boiling-liquid expanding-vapour explosion (BLEVE) of a road tank. It is suggested to estimate this probability by a combined application of stochastic simulation and deterministic models used to predict a thermal effect of a BLEVE fireball. A development of a fragility function expressing the probability of ignition of the roadside object is discussed. The fragility function is integrated into the simulation-based procedure of an estimation of the thermal damage probability. The approach proposed in this study is illustrated by an example which considers an assessment of thermal damage to a reservoir built in the vicinity of a road used for transportation of liquefied gases.

Detection of Corrosion Processes and Fatigue Cracks by Means of Acoustic Emission Monitoring

Kurzfassung Fatigue crack growth and active corrosion processes are the main causes for structural failures of transport products like road tankers, railway tank cars, and ships. Within the 7th EC framework programme the aim of project CORFAT is to develop a new monitoring technology based on acoustic emission testing (AT) of the structural integrity in terms of proceeding degradation. Differentiation of acoustic emission (AE) signals of real degradation processes by fatigue crack growth or active corrosion from operational or environmental background noise requires the signal classification using also pattern recognition. Therefore, a data base of AE signals related to the different source mechanisms was built up experimentally. In this article selected results of corrosion and fatigue tests in the laboratory as well as results of monitoring background noise during moving of a road tanker are described.

Heuristic Approach to Fleet Composition Problem

The paper deals with the Fleet Composition Problem (FCP) for a 2-echelon fuel distribution system, composed of a fuel regional warehouse (depot) and 100 gas stations (customers). The customers’ orders include random quantities of 4 types of fuel, which are distributed by a specialized fleet of road tankers. The fleet includes 4- and 8-chamber tankers that are characterized by different load capacities and fixed and variable costs. Since different types of fuel cannot be mixed together during transportation process specific assignment of orders (transportation tasks) to the vehicles (their chambers) is required. The decision problem consists in composing an optimal fleet of tankers, i.e. in defining optimal types of tankers to be used and an optimal number of vehicles in each type. It is considered as a vehicle assignment problem in which different types of vehicles are assigned to customers’ orders and formulated as a single objective mathematical programming problem, where the optimization criterion is a total daily distribution cost. Two alternative formulations of the decision problem are proposed, based on different definitions of the vehicles to be assigned to transportation tasks. To solve the problem, represented by both formulations, specialized alternative heuristic procedures are constructed. They are based on: local search (LS), evolutionary algorithms (EA) and hybrid algorithm (LS + EA). Computational experiments are carried out and their results are presented and compared in the paper.

A societal risk study for transportation of class-3 hazmats – A case of Indian state highways

United Nations Class-3 hazardous materials (hazmats) are basically liquid products and transported in road tankers under ambient temperature and atmospheric pressure. They are mostly flammables and some of them are toxic (e.g. benzene) as well. The spillages due to collision related incidents involving the road tankers, carrying such hazmats through highways, pose not only flammability hazards due to pool fire, flash fire and vapor cloud explosion (VCE), but create substantial toxic hazards also. The paper presents the risk-based study of route evaluation of two state highways and one urban city road in western India on account of transportation of class-3 hazmats, namely benzene, toluene, p-xylene, methanol, cyclohexane and acetone. A comparative evaluation of study routes was undertaken based on their societal risks presented in terms of F–N curves and assessed against HSE, UK as well as VROM, The Netherlands risk acceptance criteria. Societal risks contribution of cyclohexane to the overall flammability risk mainly VCE is found to be the highest followed by acetone and benzene compared to other study hazmats. This is due to highly explosive nature of cyclohexane resulting into vapor cloud explosion. While acetone and methanol pool fires are likely to cause larger area of damage compared to others, benzene supersedes others as far as toxicity risk is concerned and larger evacuation area is encountered, as it poses greater Immediately Dangerous to Life or Health (IDLH) distance than others. Besides, study of initial isolation distance following an accident in case of benzene tanker found that benzene spillage requires larger initial isolation distance than others and so are the day and night protective action zone distances.

SIMULATION-BASED PREDICTING THE POSITION OF ROAD TANK EXPLOSIONS. PART II: A CASE STUDY

A case study describing a simulation-based prediction of geometric characteristics of a road tank accident is presented. The case study evaluates the performance of the accident prediction model proposed in the first part of this study (Vaidogas et al. 2012). The prediction of accident characteristics is decomposed into three tasks: (i) prediction of the longitudinal rest position of the tank vehicle within the road segment under analysis; (ii) prediction of the transverse rest position with respect to road centreline; and (iii) prediction of the departure angle of the tank. These tasks are performed by applying stochastic (Monte Carlo) simulation. The results of the prediction are simulated samples of the geometric accident characteristics. These samples are considered to be input information for the assessment of risk posed by a potential explosion of tank vehicle vessel. In this case study, the potential targets of the explosion are three reservoirs built in the roadside territory. The case study presents and discusses in detail probabilistic models used for the simulation. It is stated that a considerable part of these models are chosen subjectively due to scarcity of circumstantial data on road tank accidents. The predictive Bayesian approach to risk assessment is used as a methodological basis of the simulation. Results of the simulation are intended to be utilised for increasing the safety of transportation of hazardous materials by road tanks.

SIMULATION-BASED PREDICTING THE POSITION OF ROAD TANK EXPLOSIONS. PART I: DATA AND MODELS

Road tankers used for the transportation of flammable liquids and liquefied gases can be involved in accidents which escalate into fires and the so-called boiling liquid expanding vapour explosions. The damaging effects of these phenomena on roadside property depend on the position and orientation of exploding tanks in relation to vulnerable roadside objects. This study presents a simulation-based approach to the prediction of the position of road tank explosions. The position is expressed by longitudinal and transverse rest position of an exploding tank as well as departure angle of the tank. As a part of this study, data on transverse rest position and departure angle was collected and used to fit probability distributions which express uncertainties in these circumstantial characteristics of road tank accidents. It was found that data on the longitudinal rest position is difficult to obtain and modelling this accident characteristic will have to rely on a subjective specification of probability distributions. Such distributions can be chosen by applying approaches used in the field of quantitative risk assessment. Probability distributions, partly subjective and partly based on hard data, are applied to simulate values of potential explosion coordinates. The simulation results have the premise to be applied to forecasting mechanical and thermal effects of explosions on road and assessing damage from them. A case study used to evaluate the performance of the models proposed in this study is presented in the second part of the paper.