谁能准确的翻译此句模具英文短句的含义?!

myjobpeter

<P>The compressibility of  plastic can be observed by blocking off the nozzle and then pressing the injection button.The ram will jump forward when the pressure is applied,spring back when the pressure is released.<BR><BR><BR>Thanks kindly man!</P>

jiey

<P>通过堵住喷嘴，按下注射按钮可以观察到塑料的可压缩性</P>
<P>施加压力时，（驱动螺杆的液压）活塞前进，释放压力时，活塞回弹</P>

joyfull

<P>jiey 翻译的那么好！我就只有看看的份了</P>

netsking

暂时搞不懂~~hoho~~还要努力!!!