Business connections at networking events are great. Whatever the case, do not churn the entire event away in a single endeavor. Nothing says that you need to engage in a dozen different conversations over the course of an hour. Two or three is plenty. Remember this is not speed dating, rather, its networking (building relationships). Given that, you should develop some ways of moving on. As with anything else, honesty is the best policy.
Here are some great lines for doing that:
• “Thanks for your time. I told myself I would meet three interesting people at this. I have two more to go.”
• “There is someone over there that I need to connect with.”
• “Is there anyone here in particular you would like to meet? I would be glad to introduce you.”