... Φ20mm, Φ25mm, Φ32mm, Φ38mm, Φ42mm, Φ50mm, Φ100mm and other dimensions protective sleeve of the crystallizing dish for various irregular-shaped products ... graphite mold is installed, of which the threads can’t be screwed completely and there should be 2-3 threads ... not only convenient, but also difficult to damage the protective sleeve. Protective sleeve and inner liner usde for oxygen-free copper ...