Like havasu said, you need to be more specific.
I know what you are asking, but you can't hang steel pipe on vinyl siding. The pipe supports need to be anchored to the wall studs, assuming it is a wooden frame building. And depending on the size of the pipe and the service of the pipe, the answer will vary.
And you need to consider rust stains if you are talking about steel or even galvanized pipe. Copper or stainless piping or tubing may be a better option, depending on the quantity or pipe you are needing and the service.