Comparison Between Counter Rotating Conical Twin-screw Extruder and Parallel Twin-screw Extruder

Ningbo Fangli Technology Co., Ltd. is a mechanical equipment manufacturer with nearly 30 years’ experiences of plastic pipe extrusion equipment, new environmental protection and new materials equipment. Since its establishment Fangli has been developed based on user’s demands. Through continuous improvement, independent R&D on the core technology and digestion & absorption of advanced technology and other means, we have developed PVC pipe extrusion line, PP-R pipe extrusion line, PE water supply / gas pipe extrusion line, which was recommended by the Chinese Ministry of Construction to replace imported products. We have gained the title of “First-class Brand in Zhejiang Province”.

According to the rotation direction of twin-screw extruder, it can be divided into two types: co rotating extruder and counter rotating extruder. Co rotating twin-screw extruder means that the rotation direction of two screws is the same when they work; The opposite direction extruder refers to that the rotation direction of two screws is opposite when they work. Today, we will briefly introduce and compare the characteristics of counter rotating conical twin-screw extruder and counter rotating parallel twin-screw extruder.

Performance and structure characteristics of counter rotating conical twin-screw extruder and parallel twin-screw extruder

1. The similarities between parallel and conical twin-screw extruder are the same, and the conveying mechanism of forced forward material is the same; good mixing plasticization ability and dehydration volatilization ability; basically the same practicability for the molding process of materials and plastic products

2. Differences between parallel and conical twin-screw extruders

1) Diameter: the diameter of parallel twin-screw is the same, and the diameter of small end of conical twin-screw is different from that of large end.

2) Concentric distance: the center distance of the flat twin screw is the same, the two axes of the conical twin screw are at an included angle, and the size of the center distance changes along the axis.

3) Length diameter ratio: parallel twin screw (L / D) refers to the ratio of the effective part length of the screw to the outer circle of the screw, and conical twin screw (L / D) refers to the ratio of the effective part length of the screw to the average value of large end diameter and small end diameter.