2014年1月13日星期一

Supporting base product is currently widely used in the world, forming the casting process

Support base is a key and important part of the railway bogie truck on its product quality and performance of the railway wagon speed , overloading has an important impact . Supporting base product is currently widely used in the world, casting forming. In recent years , with rail transport to improve on overloading, high-speed requirements of the key components of the support base is also increasing  Stainless steel needle valve  inherent product defects steel support base exists ( the mechanical properties of steel castings itself , fatigue toughness, resistance impact is not high , casting products exist unavoidable porosity , shrinkage , inclusions, cracks, etc. ) for the safe operation of high-speed rail has been a threat. Improve the overall mechanical properties of the product 's support base is a major reform and structural adjustment of China's Ministry of Railways to resolve rail transport facing the implementation of overloading, speed , security,  Instrument manifolds  , major issues need to be addressed to improve the effectiveness and efficiency of transportation . To ensure the safety and reliability of the rail wagons running speed , the paper creatively put forward the reform of the support base cast- forging process solutions to improve their mechanical properties. Since the original steel support base products of complex shape , casting the presence of high-gluten product support base , thin-walled structures , to bring support base increased difficulty forging casting change .

Ball has been used as a cutting device used in high temperature and high pressure piping conditions

Since the development of materials and manufacturing technology, pipeline ball valves have been used as a cutting device used in high temperature and pressure conditions. Production of high temperature and pressure valve metal seal valve in supercritical thermal power units are used, replacing the original cut-off valve and the valve, its bubble-tight performance and longer life than traditional globe valves and gate valves. High parameters and high-performance steel ball valve body has not meet the requirements, so a better toughness, higher reliability of forged steel body is very necessary. Structural design forged steel ball valve  Stainless steel needle valve  valve body design first thing to consider forging process, namely the forging process less than a block, a small margin, shape and size close to finished parts, material utilization. Consider the economy, as far as  High pressure ball valve  process of forging equipment, forging equipment because of the large and special use fee is high, while the cost of mold manufacture and use is also more expensive. Forged steel ball valve has two and three-piece. Two-piece body structure more suitable for forging, the body needs to squeeze in a closed die forging, large deformation force requirements, require large forging equipment.

2013年12月9日星期一

Research on heat transfer process plays a very important role in the development of the engine

Due to new technologies such as new combustion system, pressurized, low loss, high strengthen,  Instrumentation ball valve  and the use of alternative fuels, resulting in increased engine heat load. Therefore, the study of heat transfer process plays a very important role in the development of the engine . heat load leads to critical engine parts, such as  Instrument manifolds , pistons, cylinder heads and other thermal fatigue failure, affecting the safety and reliability of the engine is running this paper flow - solid coupling method on the engine exhaust manifold heat stress analyzes, the results of the analysis presented manifold improvements.

The exhaust manifold is the most important part of the engine exhaust system

The exhaust manifold is the most important part of the exhaust system of the engine , the engine is in the middle of the engine exhaust system and the subsequent coupling hub. Since the cylinder head and the engine is directly connected , in the role of high-temperature exhaust gas discharged from the engine , the larger the impact hot exhaust manifold . The complex structure of the exhaust manifold and the temperature distribution is uneven, has long been under the joint action of  Instrument manifolds  and alternating stresses , easily lead to heat crack initiation and expansion , and with the requirements of lightweight vehicles , many of the exhaust manifold by thin-walled tube made ​​. Therefore, in the design and development process of the exhaust manifold , an important guiding significance for its thermal load research . First, based on the engine parameters and  Stainless steel needle valve layout assembly, 3D modeling software application to establish a model of a gasoline engine exhaust manifold . Secondly , the United CFD simulation software and FEA analysis software to predict the exhaust manifold at rated conditions of temperature field, thermal stress and deformation. Finally, the simulation engine in the normal operation state and stop the cooling cycle two , an equivalent plastic strain as the reference standard , the reliability evaluation manifold . The results show that the exhaust manifold is closely related to the complexity of the conditions of temperature distribution and heat and exhaust manifold , exhaust manifold heat stress release focused on the stiffness of the weak structure transition region.

Gasoline stainless steel exhaust manifold airflow performance, thermal stress, thermal mode, performance thermoplastics such as numerical analysis

As cars become a trend and lightweight supercharged engine exhaust temperature brought, stainless steel exhaust manifold has been widely used with gasoline engines. Therefore, this paper has important value engineering studies Gasoline stainless steel exhaust manifold heat load. Analysis, combined with the simulation results to optimize the structure of the exhaust manifold designed to meet product  Stainless steel needle valve  of this article for a gasoline engine airflow performance stainless steel exhaust manifold, heat stress, heat mode, the thermoplastic properties of numerical simulation. Firstly, the flow field through a mathematical model,  Valve manifold  knowledge of fluid dynamics, simulation software for the flow field in the case of the engine exhaust manifold all conditions of different cylinders turned analyzed were obtained pressure distribution and flow lines distribution.

Using fiber grating sensing technology and devices and to achieve a downhole flow control valves without interference signal transmission

Since the microcontroller slice mining technology began to use flow control system for traffic control, significantly increased the rate of oil extraction. In this context, for the precise control and information flow can not interfere with a serious problem,  Instrument valve manifolds  a fiber grating based sensing downhole flow control valve opening detection system. The system uses fiber optic sensing technology and devices, and to achieve a downhole flow control valves  Stainless steel needle valve  signal transmission, can also get traffic information in real time underground, reducing the traditional routine operations. Introduces the research status of downhole flow control valves, flow made ​​using fiber grating detection methods.

The downstream part of the riser is circulating fluidized particle circulation loop

The downstream part of the riser is circulating fluidized particle circulation loop. Mobile phase flow characteristics within the riser of a particle along the high gravity from low-end to high-pressure flow of the lower end, this approach has led to volatility in the flow stream state of diversity and flow processes. As part of a circulating fluidized bed riser particles circulatory system, usually installed with a valve for  Instrumentation ball valve  mass flow rate and control of a circulating fluidized bed, such as fluidized catalytic cracker (FCC) of renewable inclined tube slide valve and pending Health chute slide valve. However, the valve  Instrument needle valve  is different from the gas-solid flow valves generally fluid valve opening change will affect the flow pattern inside the standpipe valve before and after the gas-solid flow valve, causing the valve opening change the particle changes in flow rate is a nonlinear relationship, thereby affecting the regulatory effect of the valve. Riser on the particles flow through the valve orifice similar nesting.