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Gate valves provide sealing with metal-to-metal friction. When the right interior parts are selected, and the production is not made according to the proper design criteria, internal leaks occur in the valves in the medium term. Considering the ideal pressure, velocity equations and designs suitable for the process can be realized by determining the nominal pressure and velocity curves. This study designed a standard gate valve with 8-inch connection dimensions. Computational Fluid Dynamics (CFD) method investigated split, flexible, and solid wedge types of the designed valve, 0.5, 1, and 2 m/s flow velocities for zero, four and five-degree wedge closing angles and 20 mm, 40 mm, 60 mm, 90 mm, and 120 mm opening wedge positions. Ansys Fluent software was used for the analyses. Mesh optimization was performed for the ideal mesh number and analyzed according to the ideal mesh number. The k-Epsilon turbulence model was used for simulations. The same situations were repeated for a parallel wedge (0-degree wedge seating angle). The lowest pressure distribution and pressure loss occurred in the parallel wedge compared to the opening position of other types of wedges. The best gate type obtained from the analysis results was determined, and an experimental tightness test was performed. It can be said that the soft seat gate valve, designed according to the results of the sealing test, gives approximately 2.5 times more opening-closing life than the metal gate valve, thus reducing the maintenance-repair costs. [ABSTRACT FROM AUTHOR]

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The rate of discharge in pipelines can be controlled using a gate valve. A wheel located at the top of a stem that features a round disc (called the gate) at its top can turn the gate. Each time the wheel rotates, a distinct linear disc movement is produced, which modifies the flow region. An experiment is presented in this paper that details the transition of the gate valve from a device that controls flow to one that measures flow. The experiment is conducted on a regular gate valve as well as a gate valve that has a rubber sleeve. The CFD analysis of a standard gate valve and one that has been altered is explained, and the results of the experimental investigation are utilised to support the findings of the CFD study. The experimental investigation demonstrated that the modified gate valve has the ability to function as a flow metre by incorporating a piezometer at both ends of the valve for the purpose of pressure monitoring. The findings that were obtained point to a substantial advance in the correlation that exists between disc orientation (angle) and discharge. With the help of computational fluid dynamics software, the flow through a gate valve with and without a rubber sleeve was analysed. The results of the CFD tests conducted without the rubber sleeve demonstrate that the flow rate variations are, in large part, the result of the establishment of variable separation zones on each side of the gate. In this study, the disagreement between the experimental data and the CFD findings has been analyzed, and a solution to the problem is suggested. [ABSTRACT FROM AUTHOR]

The application of a gate valve is to make a straight-inline flow of fluid with less restriction as the turbulence is created through the aperture provided in the valve body. The change in direction of the fluid creates change on the operating stress of the vale body. The paper is targeted for designing the valve body for reduction in the overall weight of the body and making it light in weight. The optimized design keeps the operating stress with operating stress within change of 5% which thereby ensures that the original stress value is not altered much. In the current manuscript the ribs of various thicknesses are proposed those are to be welded across the outer periphery of the body. The ribs provided on the periphery are substitutes for the reduction in the weight. The sensitivity analysis along with the change in the materials is analyzed in the manuscript. The complete optimization is valve body is done by topology optimization tool in ANSYS. This paper help and give an aim for researchers on optimizing the gate valve body with help of finite element analysis (FEA) and optimized design by adding ribs to the gate valve body to reduce the stress and deformation. [ABSTRACT FROM AUTHOR]

In order to explore the influence of different types of valves on shutdown characteristics of delivery system, this paper builds a 3D CFD numerical simulation model including centrifugal pump, outlet valves and pipelines with the dynamic mesh and sliding mesh methods. The inner and outer flow characteristics are obtained. The results show that with the same closing law, the shutdown characteristics are similar when equipped with butterfly and ball valves, and has obvious difference in the second half of closing process when equipped with the gate valve. The main reason for the difference is that the gate valve has a weaker shut-off ability compared with butterfly and ball valves. Shorter closing time would make the timing corresponding to reverse extreme values to move backward, and therefore the difference between reverse extreme values would be larger when equipped with different types of valves. This study reveals the differences of shutdown characteristics with different types of valves. [ABSTRACT FROM AUTHOR]

This paper aims to experimentally evaluate the wear and corrosion resistance of the coated active parts surfaces of a cut off valve. This paper presents the electrochemical corrosion, hardness and wear tests of the gate valve coated surfaces with a plastic material, in order to evaluate the seat and gate valve couple behaviour in an aggressive medium containing crude oil with sand particles. Uncoated and coated surfaces were compared and evaluated by the coefficient of friction, wear rates and corrosion resistance. A comparison process between the previous results of the CFD analysis for erosion wear and the test results, at the covered gate valve, is also presented.

This paper aims to evaluate the erosion wear in coated valves where multiphase fluids containing oil and sand flow. Analysis models to evaluate the erosion rate of gate valves coated and uncoated with Everslik 1301 by using COMSOL Multiphysics 5.4 are presented. Also, based on these models, analysis results performed compare the erosion rates of coated and uncoated gate valves and evaluate the effect of the film thickness on the erosion rate. Finnie and Oka models were used to evaluate the erosion rate of the valve elements.

• Elastic stress and elastoplastic analysis to assess plastic failure were carry out. • A numerical model based on the finite element technique tool was developed. • ASME BPVC Section-VIII, Division-2 code guidelines to conducted the study was used. • Maximum von Mises stress was 200.6 MPa staying below the yield limit of the valve body. • The valve body material safety coefficient was 1.25 MPa. • Screws surpassed the yield limit by 725.72 MPa entering the plastic deformation zone. Assessing the structural integrity of valves is crucial during the development process. Design by analysis involves evaluating unconventional geometries and loads by researching and classifying stresses, then comparing them to allowable values. Although ASME BPVC Section-VIII, Division-2 does not specifically cover valves, key valve design standards reference this code. Hence, this numerical study aims to develop and apply specialized stress analysis models for evaluating plastic collapse and local failure in a rising stem-type gate valve. The methodology is developed to assess the elastic behavior of the valve under stress to evaluate plastic collapse. It is also designed to assess plastic collapse and local failure by considering the material's behavior beyond the elastic range and into the plastic deformation zone. A numerical model using the ANSYS–MECHANICAL tool was developed based on the finite element technique. The main failure modes of a rising stem-type gate valve according to ASME BPVC Section-VIII, Division-2 criteria were considered. The main contribution to valve development is providing specialized stress analysis models and numerical simulations, mainly focusing on the rising stem-type gate valve and aligning it with relevant ASME standards. The results showed that the maximum von Mises stress in the valve body was 200.6 MPa, staying below the yield limit, while the screws surpassed the yield limit with 725.72 MPa, entering the plastic deformation zone. [ABSTRACT FROM AUTHOR]

Abstract A gate valve is used to regulate discharge in pipelines. It is rotated by a wheel that is attached to a circular disc (i.e. gate) at the top of a stem. Each revolution of the wheel creates a particular linear disc movement that changes the flow zone. The paper describes the journey of gate valve from flow control device to flow measuring device and presents an experimentation on conventional gate valve and gate valve with flexible membrane pipe. The findings of experimental study are described and validated with CFD analysis of conventional and modified gate valve. The experimental study has shown that the modified gate valve can be used as flow measuring device. The results obtained represent the excellent improvement in the relationship between disc position (i.e., angle) and discharge. The results of CFD analysis for flow through gate valve with and without flexible membrane are compared. After carrying out the CFD studies without flexible membrane, it is found that, fluctuating separation zones formed on either side of gate are responsible to a great extent to the flow rate descripancies. This paper compares the experimental and CFD results and also suggests the remedy to address the problem. Article highlights Introduced simply a flexible membrane pipe inside PVC to convert gate valve into flow measuring device. Reduction in flow separation and fluctuation in flow rate. Smooth flow rate even though gate valve opening is small.

Transient control of process valves, including opening and closing processes, is consistently encountered in many fluid transportation and control industries. During opening and closing processes, valve-induced transient flow presents different unstable flow characteristics. This transient valve-induced unstable flow that develops along the pipeline can cause violent pressure and velocity fluctuations that considerably influence accurate flow measurement downstream. In this paper, gate valve-induced flow characteristics during opening and closing processes were comparatively studied. An experimental system was developed to monitor the downstream pressure along the pipeline, and corresponding transient numerical simulations were performed on opening and closing processes using a user-defined function and dynamic grid technology. The pressure distributions along the pipeline's downstream area during valve opening and closing processes were investigated to verify the accuracy of the numerical simulation. The mechanism of transient flow difference under the same valve opening during opening and closing processes was determined to be a hysteresis effect. The jet flow intensity under a small valve opening in the opening process was greater than that in the closing process, and the difference in flow field under the 50% valve opening was the largest. Moreover, the velocity and turbulent kinetic energy distributions in different downstream cross-sections during valve opening and closing processes were comparatively analyzed. The change rate of the maximum turbulent kinetic energy was introduced to further analyze the different effects of opening and closing processes on the transient flow stability downstream of the valve. Results showed that the flow stability between 40% and 50% valve opening was the worst irrespective of the adjustment process, that is, a large pipeline distance was required to stabilize this transient flow. This study helps in understanding transient valve-induced flow characteristics in fluid transportation pipelines and provides guidance for accurate flow metering industrial applications. [ABSTRACT FROM AUTHOR]

Control valves are generally flow control equipment is utilized in a variety of sectors. The authors' modeling and simulation studies of various control valves are reviewed in this study. The findings of this research enable users to comprehend the flow pattern of a valve at various flow rates, as well as identify approaches for improving the valve's function. A gate valve was designed using Computational Fluid Dynamics (CFD) and CFD-powered software. The valve coefficient (Cv), often known as the flow coefficient, is a commonly used valve parameter. This paper presents the results of Flow Coefficient Analysis research. [ABSTRACT FROM AUTHOR]

Gate valves are essential control components in pneumatic conveying systems and often experience erosion on their sealing structures due to impacts from solid particles. The erosion leads to a degradation of the sealing effectiveness and, in severe cases, system malfunction. To address this issue, a numerical model based on computational fluid dynamics (CFD) is developed for the simplified two-dimensional gate valve. The two-way Euler-Lagrange method is utilized to investigate the characteristics of gas-solid two-phase flow and erosion rate. The simulation procedure is verified by comparing the simulation results with experimental data. Results show that the sealing surface separates the free shear layer above the cavity and a low-velocity zone is created on the sealing surface. The particles moving at the downstream bottom are the main particles that impact the sealing surface. The erosion results show that the maximum erosion rate occurs near the top of the sealing surface. And the low-velocity zone reduces the erosion rate within that region. Particle diameter, gas velocity, and valve opening have an important effect on erosion on the sealing surface. The erosion rate increases as the valve opening decreases. The value of the maximum erosion rate increases with particle diameter and gas velocity, and its position changes. Finally, based on the established numerical model, a prediction model for the sealing surface erosion rate is constructed using the surrogate model approach. [Display omitted] • A numerical model for gas-solid flow and erosion of a gate valve is developed. • Most particles that hit the sealing surface are from the bottom of the upstream. • The erosion rate of the sealing surface increases as the valve opening decreases. • The core erosion area is located in the upper region of the sealing surface. • The KRG model accurately predicts the wall erosion rate. [ABSTRACT FROM AUTHOR]

Nested Delft 3D and Hydrus 1D models were applied to simulate variations in the hydrological process of tidal creeks, soil water, and salt transport in the soil profile of the reconstruction area in the Yellow River Delta under six gate dam scenarios. The results showed that the gate dam set up near the sea area was more conducive to reducing the variation range of water depth in the reconstruction area. The water depth changes in scenarios with 6 m gate valves were higher than those with 3 m sluice valves in the same gate dam location. The variations in surface water salinity, cumulative flooding time, flooding frequency, and cumulative infiltration in each scenario were similar to those for water depth. Rapid changes in soil water and salt content occurred in each scenario in periods without flooding. The fluctuation of soil salt content in different soil layers was contrary to the changes in soil water content. The overall difference in the soil salt contents and soil water content of the soil profile in scenarios with a gate dam near the sea was relatively larger than that of those with a gate dam near the shore. Obvious differences in both the soil water content and soil salt content between scenarios with 3 m and 6 m gate valves were not observed. Our results contribute to the understanding of the function of gate dams in controlling soil water and salt content in coastal wetlands. [ABSTRACT FROM AUTHOR]

As a very important element of most water supply systems, valves are exposed to the effects of strong hydrodynamic forces. When exposed to large physical quantities, the valve and piping can be damaged, which could endanger the performance of a water supply system. This is the main reason why it is necessary to foresee and determine the maximum values of velocity, pressure and other physical quantities that can occur in the system under certain conditions. Predicting extreme conditions allows us to correctly size the valve for the expected conditions to which the valve might be exposed, which is also the main objective of this paper. One of the methods for predicting and determining extreme values on a valve is to perform a simulation with computational fluid dynamics (CFD). This is exactly the method used in the preparation of this paper with the aim of gaining insight into the physical magnitudes for models of gate valves positioned inside a pipe under characteristic degrees of valve closure. The Ansys CFX 19.1 and Ansys Fluent 19.1 software was used to simulate the hydrodynamic analysis and obtain the required results. The hydrodynamic analysis was performed for four opening degrees of gate valve

A performance evaluation technology was studied for the performance evaluation of high temperature forging steel gate valve based on the American Society of Mechanical Engineers (ASME) code and finite element analysis method.In order to ensure the safe and reliable operation of the gate valve under high temperature conditions, a method of evaluating the temperature field and stress field for the high temperature forging steel gate valve by finite element software Ansys was introduced. The temperature field and total stress field of the valve was calculated, so as to perform the stress evaluation and estimate the structural performance.The results show that the height of the bonnet cylinder is sufficient, the design area of the heat sink is reasonable, and the pressure-bearing boundary components can meet the strength requirements, which would have good prospects in engineering apparitions.

Nested Delft 3D and Hydrus 1D models were applied to simulate variations in the hydrological process of tidal creeks, soil water, and salt transport in the soil profile of the reconstruction area in the Yellow River Delta under six gate dam scenarios. The results showed that the gate dam set up near the sea area was more conducive to reducing the variation range of water depth in the reconstruction area. The water depth changes in scenarios with 6 m gate valves were higher than those with 3 m sluice valves in the same gate dam location. The variations in surface water salinity, cumulative flooding time, flooding frequency, and cumulative infiltration in each scenario were similar to those for water depth. Rapid changes in soil water and salt content occurred in each scenario in periods without flooding. The fluctuation of soil salt content in different soil layers was contrary to the changes in soil water content. The overall difference in the soil salt contents and soil water content of the soil profile in scenarios with a gate dam near the sea was relatively larger than that of those with a gate dam near the shore. Obvious differences in both the soil water content and soil salt content between scenarios with 3 m and 6 m gate valves were not observed. Our results contribute to the understanding of the function of gate dams in controlling soil water and salt content in coastal wetlands.

As a very important element of most water supply systems, valves are exposed to the effects of strong hydrodynamic forces. When exposed to large physical quantities, the valve and piping can be damaged, which could endanger the performance of a water supply system. This is the main reason why it is necessary to foresee and determine the maximum values of velocity, pressure and other physical quantities that can occur in the system under certain conditions. Predicting extreme conditions allows us to correctly size the valve for the expected conditions to which the valve might be exposed, which is also the main objective of this paper. One of the methods for predicting and determining extreme values on a valve is to perform a simulation with computational fluid dynamics (CFD). This is exactly the method used in the preparation of this paper with the aim of gaining insight into the physical magnitudes for models of gate valves positioned inside a pipe under characteristic degrees of valve closure. The Ansys CFX 19.1 and Ansys Fluent 19.1 software was used to simulate the hydrodynamic analysis and obtain the required results. The hydrodynamic analysis was performed for four opening degrees of gate valve. [ABSTRACT FROM AUTHOR]

Gate valves are important pipeline components in pneumatic conveying systems, and they were eroded severely by the impact of solid particles. In this study, the CFD-DEM simulation method was adopted to study the gas–solid two-phase flow characteristics and erosion characteristics of the gate valve. The accuracy of the simulation was validated by comparing the simulation and experimental data. Results show that a high-speed jet flow appears under the flashboard and induces a free shear layer, and the free shear layer attaches at the rear wall of the cavity. Particle distribution shows that the particle number at the upstream of the flashboard increases with decreasing valve opening. The particle number inside the cavity has a similar trend. The erosion results indicate that the number of particles plays an important role in erosion. The range of the erosion gradient region and the maximum erosion rate decrease with increasing particle size. Erosion of the cavity is more serious than that of the flashboard. Unlabelled Image • 2D gate valves with various relative opening were investigated. • CFD-DEM method was used to study gas-solid flow and particle erosion. • Relative opening has significant effect on gas flow and particle distributions. • The number of particles plays an important role in erosion. • Erosion of the cavity is more serious than that of the flashboard. [ABSTRACT FROM AUTHOR]

This paper presents an experimental investigation of the pressure drop (DP) through valves in vertical upward flows. Experiments were carried out using a 1?" (DN 32) ball and gate valve. Five opening areas have been investigated from fully open to the nearly fully closed valve, using air with a superficial velocity of 0-3.5 m/s and water 0.05-0.91 m/s. These ranges cover single-phase and the bubbly, slug and churn two-phase flow regimes. It was found that for the single-phase flow experiments, the valve coefficient increases with the valve opening and is the same, in both valves, for the openings smaller than 40%. The single-phase pressure drop increases with the liquid flowrate and decreases with the opening area. The two-phase flow pressure drop was found considerably increased by reducing the opening area for both valves. It reaches its maximum values at 20% opening for the ball valve and 19% opening for the gate valve. It was also inferred that at fully opening condition, the two-phase flow multiplier, for both valves, has been found close to unity for most of the tested flow conditions. For 40 and 20% valve openings the two-phase multiplier decreases in the power-law with liquid holdup for the studied flow conditions. Models proposed originally for evaluating the pressure drop through an orifice in single-phase and two-phase flows were also applied and assessed in the present experimental data. [ABSTRACT FROM AUTHOR]

The constrained reaction volume (CRV) method for shock-tube experiments makes it possible to conduct chemical kinetics studies at nearly constant pressure while inhibiting remote ignition. The application of end-wall imaging revealed, however, that CRV experiments are susceptible to vertical stratification at the interface of the test and buffer gases. This work identifies gravity currents as the mechanism leading to the test gas stratification, providing both a theoretical development and experimental investigation of their behavior in a shock tube. Parametric studies are conducted with both the gate valve and stage-filled CRV methods using a novel beam-split laser absorption diagnostic. The speed of gravity-current-induced mixing in both gate valve and stage-filled CRV experiments is shown to depend on the molecular weight matching of the gases and the fill pressure. Mixing velocity in gate valve experiments is shown not to depend on the gate valve speed. In stage-filled experiments, mixing time is seen to be a strong function of the test gas length. Recommended practices for avoiding gravity-current-induced mixing and stratification are described, including gas density matching, utilizing double diaphragms, increasing test gas length in stage-filled experiments, and implementing a gas interface diagnostic. [ABSTRACT FROM AUTHOR]

EPDM O-rings of gate valves employed for the construction of a second-generation accelerator for the production of neutron-rich Radioactive Ion Beams were studied in order to assess their sealing performance both during the facility service time and the post-service storage phase. Several O-ring specimens were at first exposed to different dose levels of mixed neutron and gamma radiations. Correspondent modifications of physical and mechanical properties of the material were investigated by means of uniaxial tensile tests, dynamic mechanical analyses, aging, compression set and vacuum leak tests. A hyperelastic strain energy function was adopted to fit the mechanical response of the material as a function of the absorbed dose. The minimum squeeze degree that guarantees O-ring sealing efficiency at different irradiation levels was determined by varying the interference between O-rings and grooves. A finite element model of the vacuum leak test was then set up to assess the contact pressure level required to ensure sealing. Numerical simulations of the gate valve main O-ring were subsequently carried out. By comparison of the predicted contact pressure and strain levels with experimental results, a life prediction map, as function of the service time, the storage time and the O-ring squeeze degree, was proposed. [ABSTRACT FROM AUTHOR]