I read it as one end being fixed in both x and y, and the other only in y, thus free to move so as to allow buckling, like http://upload.wikimedia.org/wikipedia/commons/5/54/Buckled_column.png" Is that the problem you're describing, karthickaero1?
What SteamKing said seems like a good answer, I'd just like to add one thing: Pumps like to work in either a fully liquid or fully gaseous regime. This is why the condenser completely condenses the working fluid. If the working fluid were to have some gaseous component to it, you run the risk of...