Improvement of the wear-resistant "ИГР" shut-off unit of oil and gas reinforcement

Analysis of the geometric features of the flow path of the operating gate and ball valves of tube fittings made it possible to establish the zones of formation of the most intense blocking of the flow of the polluted medium, the speed of which is a significant factor in its aggressiveness. Recommendations for improving the effectiveness of the protective functions of the moving parts of the shut-off units are given. Keywords: slide gate valve, ball valve, shut-off unit, passage area, relief grooves, technical ceramics. [email protected]

Non-Structural Damage Verification of the High Pressure Pump Assembly Ball Valve in the Gasoline Direct Injection Vehicle System

The injection pressure of the gasoline direct injection vehicle is currently developing from the low pressure to the high pressure, and the increase of the injection pressure has brought various damage problems to the high pressure pump structure. These problems should be solved urgently. In this paper, the damage problem of the high pressure pump unloading valve ball in a gasoline direct injection vehicle under high pressure conditions is studied. The theoretical calculation of the force of the pressure relief valve is carried out. Firstly, the equivalent friction coefficient is obtained by decoupling analysis of the statically indeterminate model. Based on this, a finite element model is established. The equivalent stress is obtained by numerical simulation. The equivalent stress is compared with the yield strength of the valve ball material to determine that the valve ball damage is a non-static damage. At the same time, the s-N curve of the probability of destruction of one-millionth of the material of the valve ball is given. Then, the fatigue numerical simulation is performed. A safety factor of 3.66 is obtained. In summary, the high pressure relief valve ball in the direct injection high pressure pump should not be a traditional structural damage under high pressure conditions. In the theoretical calculation, the tangential displacement and radial displacement of the ball are all on the micrometer level. It can be presumed that the surface damage of the valve ball is microscopic damage, such as fretting wear.

Analisis Perbedaan Tekanan Fluida pada Ball Valve Kondisi Full Closed dan Full Open dengan Computational Fluid Dynamics

Ball valve is one type of rotary motion valve. Ball valve functions as a round disc-shaped ball-like controller. Ball valve is widely used because it is easy to repair and the ability in high pressure and high temperature. The fluid flow in the ball valve does not always flow, sometimes the flow is closed. This will affect the fluid pressure in the valve. Fluid pressure is also affected due to valve open condition. This study aims to analyze the difference of the fluid pressure in ball valve -4 inch ANSI during closed condition and open condition. The method used is Computational Fluid Dynamics with f Flow Simulation Solidworks software. The analysis was performed for two valve conditions with a temperature of 425 °C. Decrease in pressure does not significantly affect the condition of the ball valve, even when the temperature of the fluid is high. The difference of fluid pressure between full closed condition and full open is only 0.01 psi.

Test Method for Rheological Behavior of Mortar for Building Work

This paper offers a test method for rheological behavior of mortars with different mobility and different composition, which are used for execution of construction work. This method is based on investigation of the interaction between the valve ball and the mortar under study and allows quick defining of experimental variables for any composition of building mortars. Certain rheological behavior will permit to calculate the design parameters of machines for specific conditions of work performance – mixing (pre-operation), pressure generation, pumping to the work site, workpiece surfacing.

A Study of Analysis and Simulation of the Valve Ball’s Lapping Instrument with a Cup Shaped Cutter

The valve ball is one of the most important parts in the ball valve. Lapping is a very important pressing method in valve ball’s production. A valve ball's lapping instrument with a cup shaped cutter, and build the lapping mathematics model is studied in this paper. To build the mathematical of valve ball, theoretical analysis and the simulation, the results proven that some key parameters could be properly controlled to improve the lapping process.

Remanufacturing of High Temperature Ball Valve by Surface Engineering Technology

Four kinds of coating materials and two kinds of brush plating materials were screened and sprayed on the surface of valve ball by plasma spraying technology and brush plated on the surface of valve seat by electrical brush technology, respectively. The wear resistance of the sealing pairs and the properties of the plasma sprayed coatings were tested. The results indicate that the sealing pair composed of the valve ball with the plasma sprayed coating of Al2O3-TiO2 and the valve seat with the brush plating layer of nickel tungsten has best combination property. The gap of the sealing pair at room temperature and the leakage rate at elevated temperature of the high temperature ball valve were obtained by FEM method and analysis method, respectively. Therefore, the open and close torque of the high temperature ball valve was determined. According to the results of the research, the failed ball valve was remanufactured, and the performance inspection was also conducted. The remanufactured ball valve has much longer service life than the original one and its sealing behavior was also improved significantly.

Overdrainage of cerebrospinal fluid caused by detachment of the pressure control cam in a programmable valve after 3-tesla magnetic resonance imaging

The authors report a rare case of overdrainage of the CSF caused by the malfunction of a Codman-Hakim programmable valve (CHPV) following a 3-T MR imaging procedure. Nine years ago this 72-year-old woman underwent ventriculoperitoneal shunt placement with a CHPV system for hydrocephalus due to subarachnoid hemorrhage. The postoperative course was uneventful and the system functioned well. A radiograph obtained immediately after 3-T MR imaging revealed that the pressure control cam in the valve system was detached from the base plate. Intracranial hypotension syndrome occurred several hours after the MR imaging study, and a CT scan revealed a decrease in ventricle size. A revision of the system promptly resolved the symptoms, and a postoperative CT scan revealed that the ventricle size was restored to normal. Examination of the extracted valve showed a Y-shaped crack in the plastic housing as well as detachment of the white marker and cam from the base plate. A reduction in the power of the flat spring to press the valve ball led to CSF overdrainage because of a loss of support by the cam. Because the patient had incurred no head injury during the day and radiographic studies of the system 5 years previously had shown detachment of the white marker, damage to the system might have been caused by a past impact. These facts may indicate that the antimagnetic performance of the system could have decreased due to a previous impact and that the strong magnetic force in a 3-T MR imaging environment might have caused detachment of the cam.

Effect of Plasma Sprayed Ceramic and Cermet Coatings on Wear-Out Failure of High Temperature Ball Valve

Three kinds of coating materials, namely Cr2O3 ceramic, Al2O3-TiO2 ceramic and WC-Co cermet, were screened and sprayed on the surface of valve ball by plasma spraying technology, and two kinds of brush plating materials, namely high speed nickel and nickel tungsten, were also screened and brush plated on the surface of valve seat by electrical brush technology. The microstructure and morphology of the plasma sprayed coatings were analyzed by means of scanning electron microscopy. The tribological properties of the plasma sprayed coatings sliding against the high speed nickel and nickel tungsten layers were investigated on a pin-on-disc friction and wear tester. The microhardness, thermal shock property and bonding strength of the coatings were also tested. The results indicate that the sealing pair composed of the valve ball with the plasma sprayed coating of Al2O3-TiO2 and the valve seat with the brush plating layer of nickel tungsten has the best combination property.