Mattress machine ----sx820i fully automatic transfer line for bonell type innerspring units is latest model for producing bonell type innerspring units. It can produce innerspring units directly from wire. Firstly the steel wire is coiled to a spring, and then transferred and inserted to the assembler by the automatic feeding system. After this, the upper and lower springs are coiled together at the same time and helical wire coiled, cut and clamped at both ends automatically. When a unit is finished, it could be ejected automatically.