... plastics, steel pipes Shanghai Baosteel, Two. Production flow: 1. Plastic Rotational Molding. 3. Pipe polished, mechanical sandblasting, electrostatic spray, ... baking.4. Steel pipes diameter is 1140MM,thick 2MM,plastic powers thick is 0.3MM5. Plate roofs material ... thick at least have 5MMWell,these products will develop children's ability of balance, independent coordination and increase their self ...