Guzobe na 1999, Qisheng nwere ihe karịrị ndị ọrụ 200 na usoro nke mmepụta dị elu, ule na akụrụngwa nyocha. Anyị isi ngwaahịa na-agụnye extrusion roba sooks, ebu roba sooks, silicone sooks, fluorosilicone sooks na ndị ọzọ na usoro ngwaahịa, n'ọtụtụ ebe etinyere na ubi nke gwongworo, ụgbọ ala, njem ụgbọala, injinịa ugbo ala, ugbo ugbo ala, agha ugbo ala wdg.