Design specification
The object of this graduation design is to design 2000t annual output U-PVC chemical pipeline workshop process. All parts of graduation design were finished by consulting relative reference. This technological design includes the introduction, recipe, molding method, gross process, twin-screw extruder molding, and equipments determine. Then the content of design was improved by the calculation of material balance, energy consumption, non-process design, economic accounting and workshop layout.
The purpose of the design is includes finishing the design inpidually with what I have learned from books and the ability to finding target data and documents by consulting relative reference.
At the stage of recipe, PVC-SG5 is chosen as the resin. Because of amorphous feature of PVC,taking into account the softening point, viscosity and lubricity, Lead Sulfate Tribasic and Dibasic lead stearate are used as a heat stabilizer. To shorten the time of the melt blend of the plasticizer to improve the uniformity of the melt structure, lower plasticizing temperature, improve the quality appearance of the product,ACR201 is used as the processing aid. To reduce costs and facilitate the molding, calcium carbonate is used as the filler. In lubricants respect, calcium stearate, polyethylene wax, paraffin and external lubricant are used to achieve good lubrication effect.