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What is ring die?

Jul. 28, 2023

1.What is ring die?

There are many advantages to choosing ring die made in China. These advantages include price, quality, transportation, and delivery.

Ring dies are ring fittings with porous surfaces. Ring molds have thin walls, and dense holes, and assembly requires high dimensional accuracy. It is one of the most important and easily worn accessories in the pellet mill.


The hardness of the ring die is ensured by high temperature carbonizing or vacuum quenching. The ring die should have a suitable die hole arrangement and compression ratio based on the product to be manufactured so that it will be more productive with the same opening area.During the production of a ring die, each step must be finished to the standard size in order to ensure that the various indicators will meet the requirements.


As raw materials are extruded into the die hole of the pellet mill, the ring die cooperates with the roller shell to produce the desired granular product. Ring dies are very easy to wear due to the constant friction of the material. As a result, a ring die's quality directly affects the extruded particles' quality.Currently, ring dies are widely used for producing animal feed, biomass pellets, pharmaceuticals, aquatic feed, livestock feed, and other pellets.

2.Application of ring die

Ring die granulation technology is widely used in the feed industry, the renewable biomass energy industry and the pharmaceutical industry. Different granulators are used for different materials, but the core part is the granulator ring die. Ring die has a great impact on improving product quality, reducing energy consumption, and reducing production costs. At the same time, the ring die is also an accessory that is very easy to wear. For this reason, it is extremely important for the manufacturer to understand the design and application of the ring die, select the correct ring die, and use and maintain the ring die properly.

3. Function of ring die

The ring die is the most important part of the pellet mill, and it is also the one with the most loss. In this stage, raw materials entering the pellet mill are transformed into granular products. The material of the ring dies pellet mill enters the working area between the die rolls from the feeding table. Under the action of centrifugal force and frictional force, the material is close to the inner wall of the ring die. With the rotation of the roller shell and ring die, the material is squeezed continuously, pressed into the die hole with a certain density, formed in the die hole, and then extruded from the die hole and cut into the granules.

4. Use of Ring Die

During the use of the ring die, the most critical part is to adjust the working gap between the ring die and the roller shell. If the gap is too large, the extrusion force is less than the frictional force of the material passing through the die hole, and the material will block the die hole and cause the machine to plug. If the gap is too small, the ring die and the roller shell will be easily damaged.


The control of the gap size requires the operator's actual operating experience and long-term experience accumulation in order to better master it.


The ring die of the pellet mill needs to be used together with the roller shell. Usually, the new ring die must be matched with the new roller shell in order to ensure that the working surface of the new ring die is pressed evenly, that is, that the ring die can maximize its use efficiency.


After granulation, if the pellet mill needs to be shut down or the ring die needs to be changed, and when the ring die is not in use for a period of time, the residual feed in the die hole should be cleaned with non-corrosive oil, so that the material can discharge smoothly when it is used again, and prevent die hole corrosion.

5.How to Choose ring die


Ring dies are important components for pelletizing machines used in a wide range of industries, from livestock feed to herbs and spices. They are normally composed of a mild steel or stainless steel cylinder with holes of a specific size, shape and number to produce the desired size, shape and quantity of pellets. In order to achieve a high level of pelletizing efficiency and a high product quality, it is important to choose the right type and size of ring die for the specific application.


When choosing a ring die, the first factor to consider is the size of the material that needs to be pelletized. This will determine the pellet size and shape required. The size of the ring die should be chosen so that the diameter of the pellet produced matches the size of the material.


Next, you must consider the application for which the ring die will be used. Several factors must be taken into account. For example, if the pellets will be used as feed for livestock, then you will need to consider the texture and nutrition content of the pellets as well as the size and shape. If the pellets are being used for other purposes such as herbs and spices, then you will need to consider which type of spices, and perhaps its grind size, as well as the size, shape and number of pellets.


Once the size, shape and number of the pellets have been established, the next step is to choose the type of ring die material. This will depend largely on the type of pelletizing machine used. Some pelletizing machines use a die made of mild steel while others use a die made of stainless steel. Mild steel dies are generally less expensive than stainless steel dies, but may require more frequent replacement than stainless steel dies. Stainless steel dies can withstand more wear than mild steel dies, resulting in a longer life.


After determining the type of material to be used, the next step is to identify the specific size and type of ring die required. The size of the die should match the size of the material to ensure an efficient pelletizing process. Additionally, the type of die required will depend on the type of pelletizing machine used. Different types of die shapes may be required for different machines, such as a flat-topped, open-ended, stepped, or counterbored die.


Finally, it is important to consider the manufacturer and quality of the ring die. The reputation of the manufacturer should be taken into account when choosing a ring die, particularly for larger and more complex dies. Good quality dies will be designed according to the specific size and shape requirements, and will be produced with precise dimensions to ensure an efficient pelletizing process with a high quality end product.


In summary, when choosing a ring die for a pelletizing machine, it is important to consider the size of the material that needs to be pelletized, the application, the type of material, the size and type of die required, as well as the quality and reputation of the manufacturer. By following these steps, a suitable ring die can be chosen to ensure an efficient pelletizing process and a high quality end product.

6.Common Issues and Troubleshooting Tips for Ring Die Pellet MillsRing die pellet mills are essential pieces of equipment in the production of wood pellets, animal feed, biomass pellets, and other product types. These mills have been designed and produced for decades, and in this time, many different issues have been encountered by operators of these mills. In this article, we will discuss some of the most common issues and troubleshooting tips for ring die pellet mills.


The first common issue is the build-up of material inside the die. This is caused by moisture in the raw material combining with heat and pressure generated by the die. As material builds up inside the die, the amount of material that can be processed is reduced and die output will be decreased. The best way to prevent this issue is to make sure that the raw material is properly conditioned before use. This involves making sure that material has the correct moisture content and that any foreign material has been removed. In addition, regularly cleaning the exterior of the die to remove any built-up material can help reduce the amount of material that builds up inside the die.


Another common issue is jammed die holes, which can occur when the die is clogged or overfilled with feed. This issue is caused by the feed being too moist or by the size of the feed particles being too large. The best way to prevent this issue is to make sure that the feed is properly conditioned before use. This involves making sure that the material has the correct moisture content and that any foreign material, such as rocks, has been removed. Additionally, using correctly sized die holes can help reduce the chances of jamming.


The third common issue is poor pellet quality. This can be caused by a number of different factors, including incorrect die size, incorrect die temperature, overfeeding, and incorrect conditioning of the feed. The best way to prevent this issue is to make sure that the pellet mill is set up properly and that the correct die size and die temperature are being used. Additionally, properly conditioning the feed before use and avoiding overfeeding can help to ensure high-quality pellets.


The fourth common issue is wear and tear on the die and rollers. This is caused by the friction of the feed against the die and rollers as it is being processed. To reduce the amount of wear and tear, it is important to make sure that the die and rollers are lubricated on a regular basis. Additionally, replacing any worn or damaged parts as soon as possible can help to extend the life of the die and rollers.


Finally, the fifth common issue is bearing failure. This is caused by a lack of lubrication or contamination of the bearing. To prevent bearing failure, it is important to make sure that the bearings are properly lubricated on a regular basis and that any contaminants are removed. Additionally, replacing any worn or damaged bearings as soon as possible can help extend the life of the bearing and reduce the chances of failure.


These are just a few of the most common issues and troubleshooting tips for ring die pellet mills. By understanding the causes of these issues and following the troubleshooting tips outlined above, operators can ensure that their mill is running at maximum efficiency and producing high-quality pellets.

7. The Role of Ring Die Design in Pellet Quality and Yields

The ring die design of a pellet mill plays an integral role in pellet quality and yields. To better understand the impact of the design, it is important to analyze the mechanical components used to produce a pellet. A roll-type pellet mill consists of four main parts – a die, rollers, an upper feeder system, and a drive system – each of which plays a critical role in forming the pellet. 


The die of a roll-type pellet mill is the most critical component of the machine. It is made from one-piece, forged steel with a hole pattern that forms the shape and size of the pellet. The hole pattern is determined by the type of feed being pelletized and the performance criteria of the final product. For example, if the goal is to produce a pellet with high durability and long shelf-life, then the hole pattern should allow for maximum exposure of the feed surface, which will make more contact with the heat generated during the compression and extrusion process, thus improving the product’s durability. On the other hand, if the goal is to produce a pellet with softer density, then the hole pattern should be designed to retain a higher amount of moisture in the feed during the process, improving the product’s elasticity. 


The ring die design of a pellet mill affects its performance in multiple ways. The die’s hole pattern is designed to maximize the product’s production rate by controlling its compression and extrusion speed. By increasing the compression speed, more pellets can be made in a shorter amount of time. However, if the compression speed is too high, the pellets can often melt and stick to the die walls or to each other. This can lead to reduced output quality and reduced yields. Similarly, if the extrusion speed is too low, too much time is required for the pellets to form a proper shape. 


The die temperature is also an important factor when it comes to pellet production. High temperatures can lead to reduced pellet quality, since excessive heat can cause thermal degradation of the feed. The higher the die temperature, the lower the pellet durability will be. Therefore, it is important to use a ring die design that minimizes the heat generated during the pelletizing process. This is typically achieved through the use of hollow die rollers and heat-dispersal chambers. Heat-dispersal chambers allow the generated heat to be dissipated over a larger surface area, thus keeping the temperature of the die at a safe level. 


Finally, the ring die design of a pellet mill affects feed consumption and how efficiently the pellets are formed. High feed consumption is often the result of improper die design, as it can lead to an inefficient compression-extrusion process. To reduce feed consumption, the hole pattern of the die should be designed to minimize any loss of material during the process. Less material lost during compression and extrusion leads to a higher pellet quality and higher yields. 


In summary, the ring die design of a pellet mill has a tremendous impact on the pellet quality and yields. Its hole pattern should be designed to maximize the feed surface exposure for high durability pellets, while also minimizing the die temperature and feed consumption. Additionally, the die design should be optimized to control the compression and extrusion speeds, as this can help to ensure that the pellet has the desired characteristics and stability. All of these factors, when taken into account, can help to maximize the performance of a pellet mill.



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