process specification of screw and barrel: specification:Ф15-Ф360MM The ratio of length to diameter:L/D=12-45 types of screw: For good plasticizing effect,we have different design of screw barrel to meet customers demand.Gradual type,mutant type,wave type,barrier type,double screen type,shunt type,separation type,exhaust type,pin type,mixed type,double-head type,three-head type,multi head type etc.