You should be very happy that you are not banned. I've seen many people banned recently and I'm seriously scared right now. I don't know how many posts I can write without being assaulted by banning team.
Afaik, there isn't a certain number of posts that you need to accumulate in order for you to get banned. The main point for you to get banned by posting is posting nonsense post (usually bump, +1, single pictures etc.) and replies that are really far from what the topic really is. You can actually post as many as you want and as you like, as long as it is constructive and doesn't stray away from what is being tackled upon in the topic.
Have you read the forum guidelines?
Although the staff seems to miss some of the "good spammers".