By 'chevrons' I assume you mean the red and white icons representing the crewman's job / specialty? In English 'chevron' usually refers to a V shaped rank insignia, like this:
I think the icons are mostly quite clear with a few exceptions. I've tried to guess what each of them is - if I get it wrong, maybe it is not clear enough:
![](http://i.imgur.com/LRUIAQB.png)
- Torpedoes / weapons
![](http://i.imgur.com/4CENMLG.png)
- Maneuvering?? Dive control maybe?
![](http://i.imgur.com/yXCMnZD.png)
- Steering or maneuvering
![](http://i.imgur.com/SMSLDmk.png)
- Engines / propulsion
![](http://i.imgur.com/WXWqxrz.png)
- Radio communications
![](http://i.imgur.com/ZYyCYlC.png)
- He plays the drums!
![](http://i.somethingawful.com/forumsystem/emoticons/emot-rimshot.gif)
(I don't know this one)
![](http://i.imgur.com/OOEZWO7.png)
- A diver
![](http://i.imgur.com/pwp0bWv.png)
- Maybe a political officer?
I hope this helps. Keep up the good work!