Strand pelletizer

Types of strand pelletizers

A strand pelletizer is a vital component used in various manufacturing industries, including chemicals, plastics, food, and pet feeds, to convert different kinds of materials into spherical particles. These particles, also called pellets, are usually uniform in size and easy to handle. The pellets are then used as raw materials in other manufacturing processes or sold as end products. Strand pelletizers come in different types, each suitable for particular applications.

• Hot-and-cool strand pelletizers: Hot-and-cool strand pelletizers involve the two-step cooling process. First, they cool the strands with cooling water, and then they remove the strands from the cooling drum to let them cool to the room temperature on the table. These types of pelletizers are suitable for plastic recycling.
• Air-cooled strand pelletizer: An air-cooled strand pelletizer uses compressed air to cool down the strands before cutting them into pellets. This strand pelletizer is often used to process high-performance and engineering-grade materials that melt at high temperatures. It can be used with water-soluble polymers as well, but the pellets must be dried afterward to get rid of the moisture.
• water-cooled strand pelletizer: The water-cooled strand pelletizer involves cooling a strand in a water bath before it is cut into strands. Water-cooled strand pelletizers offer good strand cohesion and, therefore, efficient cutting for materials that generally require low-temperature processing. 
• vacuum vented pelletizer: This type of pelletizer is suitable for processing materials that release volatiles when subjected to high temperatures. It can also be used to remove moisture from the material before processing to improve the quality of the pellets.
• central knife cutting pelletizer: In this type, the strands are cut by a knife that presses down on the strands from above. The knife is usually stationary, and the strands are cut by moving the strand through the knife. Central knife cutting pelletizers offer a wide range of cutting sizes, which is one of their key advantages.
• In a die-face-cutting pelletizer, the strands are cut right at the face of the die, usually by a set of knives that move towards the die. The die typically has round holes through which molten material is extruded in strand form. The knives then slice the strands into pellets. This type of pelletizer offers good strand control, quick cutting, and uniform pellet size.

Specifications and Maintenance of a Strand Pelletizer

Specifications

• Die Plate Size

  The die plate size determines the quantity of material that the strand pelletizer can extrude in a single cycle. The size is directly proportional to the throughput of the machinery. They are available in different widths, diameters, and lengths to cater to various production requirements.

• Cutting Speed

  It is the speed at which the strand falls. The cutting speed impacts the rate of production and consistency of pellet size. Usually, strand pelletizers have cutting speeds from 500 to 4000 strands per minute. HSI मशीनरी offer cutting speeds of 3000 to 4200 strands per minute.

• Pellet Size

  These are the diameter and length of the individual pellets. They are usually between 2-20 mm. Pellet size is dependent on application and customer specifications.

• Material Compatibility

  Various strand pelletizers can handle different types of materials. It includes thermoplastics, bio-mass, engineering plastics, and more. Each material requires a specific processing mechanism.

• Pelletizer Blade

  These are the blades used to cut strands into pellets. They can be made of stainless steel, carbon steel, or any other specialized alloy.

• Power Requirement

  The power requirement of a strand pelletizer influences the types of materials it can handle and the processing speeds it can achieve. The power is usually between 10HP to 300HP.

Maintenance

• Lubrication

  Pelletizing machines have many moving parts. Lubricating them regularly, as per the manufacturer's guidelines, is essential to keep them operating smoothly.

• Inspecting and replacing blades

  Over time, the cutting blades become dull, affecting the quality of the pellets. Regularly inspect the blades and replace them whenever necessary.

• Electrics and Controls

  Functionality of the controls and electrical connections should be inspected regularly. Look for loose connections, damaged wires, or malfunctioning switches and promptly address any issues found.

• Cleaning

  Strand pelletizing can be a messy operation as materials and strands tend to get everywhere. Therefore, cleaning it regularly is critical to preventing material buildup and contamination.

Usage scenarios of strand pelletizers

Strand pelletizers have diverse applications and are used in various industries and sectors.

• Plastic Recycling:

  The recycling industry uses strand pelletizing to process different types of plastic waste. This includes plastic bottles, containers, films, and fibers. By using strand pelletizing, the plastics can be recycled effectively, producing high-quality plastic pellets that can be used to make new products.

• Food Industry:

  Apart from plastics, strand pelletizers are also used to produce animal feed and food products. They can handle materials like underwater pelletizer corn, soybeans, and other grains. The pellets made by strand pelletizing are easy to measure and have good nutritional value. Moreover, strand pelletizers help improve processing efficiency in the food industry.

• Textile Industry:

  Strand pelletizing plays a significant role in the textile industry. It is used to process fiber materials such as polyester, nylon, and polypropylene. Pellets produced by strand pelletizing serve as the raw materials for making fibers and filaments, which are then utilized to manufacture textiles, fabrics, and non-woven products.

• Chemical Industry:

  Strand pelletizing is widely used in the chemical industry to handle polymer materials and chemical products. These materials may include engineering plastics, high-performance plastics, and other chemical additives. By utilizing strand pelletizing, the products can be shaped into pellets for easy storage, transportation, and application.

• Rubber Processing:

  Strand pelletizing also finds application in the rubber industry. It is employed to process materials like natural rubber and synthetic rubber. The pellets produced through strand pelletizing are suitable for further processing and production of rubber products, including tires and seals.

• Research and Development:

  Strand pelletizing is extensively used in research and development labs. It assists scientists and engineers in accurately measuring material processing characteristics and optimizing production techniques. Additionally, strand pelletizing enables small-scale production and testing of new materials and formulations, thereby expediting the innovation and development of new products.

How to choose strand pelletizers

For the buyers of pelletizing equipment, it is important to note that selecting the right strand pelletizer for a specific application has a lot to do with the understanding of the needs of the business. To begin with, it is important to identify the material required to be processed. Once this is identified, consider the material's characteristics, such as temperature sensitivity, moisture content, and viscosity. Next, understand the production capacity that is required for the business. This will help in knowing the precise pound-per-hour or kilogram-per-hour capacity that is needed. Other important things to consider are the space requirements, low noise operation, ease of maintenance, and any specific customization features that are needed, such as die plate configuration or downstream equipment integration.

Generally, in terms of capacities, there are strand pelletizers for small capacity, as well as those for large capacities. Anyway, it is good to know that many modern strand pelletizers have a variety of automatic features that assist operators in effortlessly managing the pelletizing process. Moreover, with several strand pelletizers available for selection, it is ideal to weigh the benefits of each kind before making a choice. The common types are the underwater strand pelletizer, the dry strand pelletizer, and the wet strand pelletizer.

When selecting a strand pelletizer, do research on the supplier and prod their knowledge about post-sale support, such as spare parts availability and technical support. It is a good idea to seek references from others who have purchased the same equipment. Remember that a meaningful partnership with the supplier can make future business easier and more successful.

Q&A

Q1: Are there any alternatives to the strand pelletizer?

A1: The underwater pelletizer is the most common alternative to the strand pelletizer. It also cuts plastic strands into pellets but does the job underwater.

Q2: What materials can strand pelletizers handle?

A2: They can handle a wide range of thermo-plastics, such as PPS, PEEK, HIPS, POM, etc. PEEK strand pelletizer makers usually get asked for equipment that can handle high-temperature plastics such as PEEK.

Q3: What are recent developments in pelletizing technology?

A3: Some recent developments in the strand pelletizing technology include improved cutting precision, enhanced automation, and the integration of environmentally sustainable practices.

Q4: How durable are strand pelletizers?

A4: These machines are built to last. With proper maintenance, they can operate for years without breaking down. However, some components will wear down faster than others. It's a good idea to stock up on spare parts and accessories.