Customs Three Rolls Calender of Plastic Sheets Extrusion Line

Basic Info.

Machinery Unit Description

The machinery unit for the coating line includes several key components that work together to apply protective coatings to steel pipes. The main components are:

1. Extruder: Responsible for melting and shaping the coating material.
2. Screen Changing Device: Ensures the removal of impurities from the melt.
3. Melt Pump: Maintains consistent pressure and flow of the melted material.
4. T-Die: Shapes the molten material into a flat film or coating.
5. 3-Roller or Multiple-Roller Calender: Flattens and smooths the coating to the desired thickness.
6. Cooling Device: Rapidly cools the coated pipe to solidify the material.
7. Edge Cutter: Trims the edges of the coating for a clean finish.
8. Haul-Off System: Pulls the coated pipe through the line at a controlled speed.
9. Plate Cutter: Cuts the coated pipe into specified lengths.
10. Winder: Rolls the finished product for storage or transportation.
11. Electrical Control System: Manages the operation of the entire machinery unit.

Working Principle

The operation of the machinery unit involves three distinct states of the hot plastics at various temperatures:

1. Glass State: The initial state where the material is rigid.
2. High Elastic State: As the temperature rises, the material becomes more pliable, allowing for shaping.
3. Glutinous and Fluid State: At higher temperatures, the material reaches a molten state, enabling it to flow through the slim gap of the die.

Following the extrusion process, the remaining procedures include:

• Calendering: Smooths and shapes the coating.
• Cooling and Shaping: Solidifies the coating to ensure proper adhesion and shape.
• Edge Cutting: Ensures a clean, uniform edge.
• Haul-Off: Controls the movement of the coated pipe.
• Cutting and Winding: Finalizes the product for delivery.

Summary

This machinery unit is essential for producing high-quality coated steel pipes, employing a systematic approach to ensure efficiency and precision throughout the coating process.