英语翻译标题：The Velocity DilemmaAnother aspect of the gating picture that needs and is receiving attention is gate velocity.Until the advent of electronic instrumentation,little thought is given to this parameter in most die casting shops.So

英语翻译标题：The Velocity DilemmaAnother aspect of the gating picture that needs and is receiving attention is gate velocity.Until the advent of electronic instrumentation,little thought is given to this parameter in most die casting shops.So
英语翻译
标题：The Velocity Dilemma
Another aspect of the gating picture that needs and is receiving attention is gate velocity.Until the advent of electronic instrumentation,little thought is given to this parameter in most die casting shops.Some students of the process are vaguely aware that there is not complete freedom to roam up and down the gate velocity scale at will.Die casting engineers have often told of grinding the gate to change its direction only to find the casting quality deteriorating*.What was happening was that as they enlarged the gate area they reduced the gate velocity,virtually canceling the possible benefits of their efforts at redirection[1] .
A survey and analysis of hundreds of gating systems in successful production dies showed a peak in the velocity distribution curve in the range of 100-150 ft/sec for aluminum and 80-120 ft/sec for zinc.Researchers who have explored the influence of gate velocity at some length have frequently reported a “no man’s land” in the velocity scale.This slump* in casting quality may occur in one range with one casting and in another range with a different casting.Generally,however,it is seen most often in the 30-50 ft-sec range.
In an effort to understand further the role of gate velocity,the DCRF is currently sponsoring additional work under Wallace at Case Western Reserve University.By means of high speed photography (5 000 frames/sec),the influence of velocity on the nature of the metal stream emerging from the gate orifice is being studied.At this time several things have been learned.
True solid front flow is a myth.Velocities as low as 15 ft/sec were seen to produce a fanlike spray.At higher velocity,the streamers tend to break up into strings of coarse discrete* globules.At still higher velocity,the particles become very fine.This may be the sort of flow referred to by die casters as “fog,” “atomized,” etc.After the nature of the stream with respect to velocity is established and the boundary zones of these modes are determined,these factors will be correlated,with casting quality.Internal and surface quality optima may very possible occur at quite different gate velocity ranges.The reader should keep in mind that we have been referring to the nature of the metal stream immediately after it emerges from the gate orifice and leaps into the open space of the mold cavity.It is clear that in actual practice the stream that starts out as a spray may very well be slowed to a small fraction of its original velocity by impinging* on as few as one or two successive* walls of the die’s convolutions*[2].Thus,those who have observed clearly round nosed,solid stream fronts after the metal has progressed some distance from the gate were not dreaming.In fact,it is probable that as the stream is bounced from one wall to another,it could not possibly retain sufficient velocity to remain a spray of liquid metal particles.
先给15分,

英语翻译标题：The Velocity DilemmaAnother aspect of the gating picture that needs and is receiving attention is gate velocity.Until the advent of electronic instrumentation,little thought is given to this parameter in most die casting shops.So
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速度窘境
另一个门图片方面，需要注意的是接收门速度。直到电子仪器的出现，没有想到，对这一在大多数商店压铸模具参数。过程有些学生模糊地知道，是不完整的自由漫游向上和向下的速度将门规模。压铸工程师常常告诉研磨大门改变方向，却发现了铸件的质量日益恶化的*.发生了什么事是，他们扩大了门区，他们降低了门的速度，实际上取消了在重定向的努力可能带来的好处[1]。
调查和浇注成功生产系统模数分析...

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速度窘境
另一个门图片方面，需要注意的是接收门速度。直到电子仪器的出现，没有想到，对这一在大多数商店压铸模具参数。过程有些学生模糊地知道，是不完整的自由漫游向上和向下的速度将门规模。压铸工程师常常告诉研磨大门改变方向，却发现了铸件的质量日益恶化的*.发生了什么事是，他们扩大了门区，他们降低了门的速度，实际上取消了在重定向的努力可能带来的好处[1]。
调查和浇注成功生产系统模数分析显示，在100-150英尺范围内的速度分布曲线的峰值/铝和80-120英尺秒/锌秒。谁曾探讨了详尽的闸门速度的影响，研究人员经常报道“没有人在速度大规模的土地”。这在铸件质量下滑*可能发生在一个范围内的铸造和一个在另一个不同的铸造范围。但是，总的来说，它是最经常出现在30-50英尺，秒范围。
为了进一步了解的大门速度的作用，DCRF目前赞助下，华莱士在凯斯西储大学的额外工作。通过对高速摄影手段（5 000帧/秒）的速度对金属孔板从门新兴流性质的影响正在研究之中。在这几件事中汲取了时间。
真正坚实的前面流是一个神话。低至速度的15英尺/秒被视为产生fanlike喷雾。在较高速度的飘带，往往分成粗的字符串组成的离散*球。在更高速度，颗粒变得非常的罚款。这可能是流动排序提到死脚轮的“雾”，“雾化”，后流速度方面的建立等性质以及这些模式的边界地带的决定，这些因素将相关与铸件质量。内部和表面质量最优，可能很可能发生在完全不同的速度范围的大门。读者应该记住，我们一直提到的金属流的性质后，立即从门孔和飞跃出现到模腔空地。显然，在实际工作上流开始作为一项喷雾很可能是由撞击*放缓到其原来的速度小部分少一个或两个连续*的模具的回旋* [2墙]。因此，那些谁清楚地观察到鼻轮，固体流后的金属已经从门口有一段距离方面是不是在做梦。事实上，很可能是由于流墙上反弹从一个到另一个，它不可能保持足够的速度继续成为液态金属颗粒喷雾。

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