I work for a big company and I walk by HB's that work in different departments sometimes. They usually acknowledge me and say hi or sometimes nothing at all from the shy ones.
I don't think club or street openers would work in this environment.
What would be good openers to use in these situations when they are walking by quick?

Hey Krush!
This is my suggestion, no routines planned out, just something easy and effective:

Next time you walk by a HB in your department, say "Hey, how's it going?" and ask them a quick question as you're walking by. She won't feel like you're tryna get into a conversation wit her cause you're both walking away from eachother. You get your answer and laugh a little, give a smile & say thanks. Presto! you've made a connection with her, you've put a smile on her face and you shown you're not needy of a conversation, but that you're not shy to talk. all that raises your value in her eyes and the game has begun.

Next time you see her, you can stop her & ask her for her name, introduce yourself & then continue walking away or start a converstation.
What is sure is that the next times you see her, you can easily start a convo, flash a smile & get one back, and then do your magic (figuratively speaking, or not)

Try that out man! And I hope the janitor doesn't mind you using his closet (if ya know what I mean )

At work it should be a lot easier because you see each other more. If you get extended eye contact just a 'hey, how is it going?' is enough. The great thing is once that is done, you can go easily into small talk because at work you have your whole job, work, company to discuss.

Another possible opener is:
You: hey, wait, are you also from the (insert specific job/sectione here - e.g. customer service)?
She: yes, no, blah blah.
You: oh, what a suprise, I have seen you here so many times but I never quite knew what you did. Anyway, I have to bounce works calling. Btw, I am fabie...
She: I am blah.
You: Pleased to meet you.

Bingo right there.

i think fabie's got it there man, i have done that, works great, nonthreatenin and great openin