Weihua Electrical Machinery is a professional manufacturer of electrical machinery products integrating design, production, sales and service.
Extruder deceleration principle
2017-06-06 15:30
Extrudable plastics are thermoplastics which melt when heated and solidify again when cooled. Where the heat of melting plastic comes from. Feed preheating and barrel/die heaters may play a role and are very important at start-up, but the motor input energy-the frictional heat generated in the barrel when the motor rotates the screw against the resistance of the viscous melt-is an important heat source for all plastics, except small systems, low-speed screws, high melt temperature plastics and extrusion coating applications. For all other operations, it is important to recognize that the barrel heater is not the primary source of heat in the operation, and thus the effect on extrusion may be less than we expected. The post-barrel temperature may still be important because it affects the rate of delivery of solids in the tine or feed.
The die and mold temperatures should generally be at or near the desired melt temperature unless they are used for some specific purpose like polishing, fluid distribution, or pressure control. Extruder Speed Reduction Principle In most extruders, the screw speed is varied by adjusting the motor speed. The motor typically rotates at full speed of about 1750rpm, but this is too fast for one extruder screw. If it is rotated at such a fast speed, too much frictional heat is generated and the residence time of the plastic is too short to produce a uniform, well-stirred melt.
Typical deceleration ratios are between 10:1 and 20:1. Stages can use either gears or pulley sets, but stages use gears and the screw is positioned on the latter large gear. In some slow running machines (such as twin screws for UPVC), there may be 3 deceleration stages and large speeds may be as low as 30rpm or low (ratio up to 60:1). On the other end, some of the very long twin screws used for mixing can run at 600rpm or faster, thus requiring a very low deceleration rate and a lot of deep cooling. Sometimes the deceleration rate is incorrectly matched to the task-there will be too much energy to use-and it is possible to add a pulley block between the motor and the deceleration stage that changes the large speed. This either increases the screw speed above the previous or reduces the large speed allowing the system to run at a large percentage of the speed. This will increase the available energy, reduce the amperage and avoid motor problems. In both cases, depending on the material and its cooling needs, the output may increase
Extruder deceleration principle
recommend reading
Key Features to Look for in a Cold Feed Rubber Extruder for Electrical Wiring
Key Features to Look for in a Cold Feed Rubber Extruder for Electrical Wiring Understanding Cold Feed Rubber Extruders Cold feed rubber extruders play a crucial role in the manufacturing of electrical wiring. These machines process raw rubber materials into various forms, ensuring they meet specific standards for electrical applications. Understanding the key features of cold feed rubber extruders
Understanding Rubber Extruders: Key Insights for the Electrical Industry
In the electrical and cable industry, the rubber extruder plays a pivotal role in the manufacturing process, particularly when it comes to producing insulation and jacketing for wires and cables. A rubber extruder is a machine that shapes rubber materials into specific profiles or forms by forcing them through a die. Understanding the fundamentals of rubber extruders can significantly enhance oper
The Essential Guide to Cable Types in Production Lines
The Essential Guide to Cable Types in Production Lines Table of Contents Introduction to Cable Types in Production Lines Understanding Different Types of Cables Single-Core vs. Multi-Core Cables: Which Is Right for You? Types of Cables Commonly Used in Production Lines Power Cables Control Cables Data Cables Specialty Cables
The Essential Role of Plastic Extruders in Cable Manufacturing
Plastic extruders play a pivotal role in the modern manufacturing of electrical wires and cables, particularly in the creation of insulation and protective coatings that ensure durability and performance. These machines are designed to melt plastic pellets and then force the molten material through a die to create continuous shapes, making them indispensable in the production of various cable comp
Comparative Analysis: Different Types of Wire and Cable Extrusion Production Lines
Comparative Analysis: Different Types of Wire and Cable Extrusion Production Lines Introduction to Wire and Cable Extrusion Extrusion is a critical process in the production of wires and cables. This procedure involves forcing molten material through a die to create a continuous product with a fixed cross-sectional profile. In the context of the electrical industry, wires and cables are pivotal fo
Understanding Cold Feed Rubber Extruders: A Key Component in Electrical Wire and Cable Manufacturing
In the realm of electrical wire and cable manufacturing, the cold feed rubber extruder stands out as a pivotal technology. This specialized piece of equipment is designed to process rubber compounds at ambient temperatures, offering several advantages over traditional extrusion methods. Understanding the functionality and benefits of cold feed rubber extruders can help manufacturers optimize their
