如何大批量生产曲轴

曲轴的加工有多种方法,可根据实际的应用场合选取最适合的方法。在选择最具竞争力的解决方案之前,必须仔细评估每种应用的需要和特点。     

从粗加工到精加工的铸铁铣削

铸铁铣削是发动机和壳体类零件制造的重要部分。在发动机制造中,正确的几何形状、良好的表面粗糙度以及全面质量保证中的零废品,都是绝对重要的目标。然而面对日益增加的成本压力,它们都黯然失色。为了满足以上所有要求,我们需要可靠高效的刀具和解决方案,例如缸体和缸盖各平面的粗铣和精铣。     

A 7 year long measurement period investigating the correlation of corrosion,deposit and fuel in a biomass fired circulated fluidized bed boiler

The present investigation involves a unique, 7 year (2001–2007) long study of corrosion and deposits on superheater tubes in a biomass fired circulated fluidized bed boiler. These measurements are correlated against the different fuels used over this period. In the earlier years, the boiler was run with a mixture of different biomass fuels and peat. In later years, recycled wood was introduced into the fuel mix. The deposit growth rate approximately doubled when the recycled wood content of the fuel was increased to 10–20%. Small amounts of chlorine and zinc were found both in the recycled wood and in the deposit layer. These elements together with alkali metals from the biomass, have the potential to form sticky compounds that increase the deposit growth rate. The corrosion rate of the superheater tubes varied over the study period. A number of possible explanations for this phenomenon are discussed.     

正确的切入方法对耐热超级合金的成功车削至关重要

要想以相对较高的生产效率来加工耐热超级合金,必须充分准备相应的加工策略。由于加工此类材料的零件时至少50%以上的工序为车削,因此其基本原则应立足于采用合适的切削刃切入方法。     

永不妥协：让声音说明一切

挑战：用新的铣刀概念提升面铣水平,提供多种不同型号满足具体需求。 解决方案：一种独特新颖的多个切削刃面铣刀——堪称高新切削刀具技术。     

可转位刀片刀具的性能改进

挑战：为立铣加工提供整体硬质合金刀具和可转位刀片刀具的双重优势。     

独特的用于硬车削的可转位刀片

现在,车削淬硬零件的切削刀具及其应用方面的最新进展,正在将车削工艺提升到更高的效率水平.作为磨削工序的替换或补充工序,硬零件车削具有诸多优势,独特的新刀片概念令这种工序更具吸引力. 最近,两家制造商在淬硬零件加工的生产效率方面产生了立竿见影的效果:生产效率分别提高116％和322％.无需更换设备,也不用引入新的加工方法,只需改变数控车床上使用的可转位刀片的类型即可实现.与之前相比,一种新型的刀片能够使刀具的进给率较之前提高三倍.众所周知,进给决定了车削时所花费的切削时间.这样一来,每年就能节省相当多的生产时间,对成本而言也是如此.     

Influence of culture conditions on metal-induced responses in a cultured rainbow trout gill epithelium

A primary culture technique for rainbow trout (Oncorhynchus mykiss) gill cells was optimized to better represent the intact gill in vivo in response to waterborne toxic metals. Modifications in cell seeding density and culture conditions resulted in a gill epithelial cell culture model, which displayed classic in vivo responses to toxic metals. Metallothionein-A (MTA), metallothionein-B (MTB), zinc transporter-1 (ZnT-1), glutathione-S-transferase (GST), and glucose-6-phosphate-dehydrogenase (G6PD) all showed dose-dependent increases in expression at the mRNA level in response to waterborne zinc. Of these genes, the change in zinc-induced expression relative to the control was greatest for MTA, MTB, and ZnT-1. MT expression was also induced by silver, lead, copper, and cadmium. Cells cultured with freshwater on the apical side maintained the net transepithelial influx of Ca2+ displayed by freshwater trout gills in vivo, and there was an active inward movement of Ca2+. Waterborne zinc applied to the apical compartment reduced the net uptake of Ca2+ by stimulating the efflux component. The use of endogenous metal-responsive gene expression and inhibition of ion transport in the developed cell culture system will facilitate studies of metal-gill interactions and may prove to have future practical applications within biomonitoring of natural waters.     

Effect of fuel injection pressure on a heavy-duty diesel engine nonvolatile particle emission

The effects of the fuel injection pressure on a heavy-duty diesel engine exhaust particle emissions were studied. Nonvolatile particle size distributions and gaseous emissions were measured at steady-state engine conditions while the fuel injection pressure was changed. An increase in the injection pressure resulted in an increase in the nonvolatile nucleation mode (core) emission at medium and at high loads. At low loads, the core was not detected. Simultaneously, a decrease in soot mode number concentration and size and an increase in the soot mode distribution width were detected at all loads. Interestingly, the emission of the core was independent of the soot mode concentration at load conditions below 50%. Depending on engine load conditions, growth of the geometric mean diameter of the core mode was also detected with increasing injection pressure. The core mode emission and also the size of the mode increased with increasing NOx emission while the soot mode size and emission decreased simultaneously.