... in park, amusement ground, district, Kindergarten, Supermarket, Garden. outdoor play system:standard steel pipe, galvanized pipe, Aluminum alloy pipe, diameter is 114cm ... solders after clean by acid and bonderizing, then polishing by machine, mould by POLYESTEY/TCICSYSTEM, and heated in high temperature, ... to cast shape at one time, surface is polished by machine, gush mould by POLYESTEY/TCICSYSTEM.