Hardness of steel rods in rod mills

Generally, HRC45~55 is required.

Wear-resistant steel rods (Huamin grinding rods) are used by numerous manufacturers that operate rod mills and coal grinding machines, such as those in cement plants, power plants, mines, quartz sand factories, silica sand factories, sand aeration plants, coal chemical industries, and aerated concrete factories. The steel rods currently in use in the market are produced by steel mills through rolling processes; they require no high level of technical precision, have extremely poor wear resistance, and result in high consumption during use, leading to significant waste of ** resources. Our company (Huamin Grinding Rods), in response to the call to **promote energy conservation for the benefit of future generations**. Targeting the consumable products currently available on the market (steel rolling rods). Therefore, our company invested heavily to hire various experts to specialize in researching this product, with the aim of developing a steel rod with higher wear resistance to replace the current consumable steel rods in use domestically. After years of research, our company has finally developed a new type of alloy wear-resistant steel rod. The wear resistance of this wear-resistant steel rod is 4 to 6 times that of a steel rod produced by rolling. Each year, it is possible to **save hundreds of thousands of tons, or even tens of millions of tons, of steel. The new type of alloy wear-resistant steel rods produced by our company (Huamin Grinding Rods) are manufactured using the latest methods; their dimensions can be adjusted to meet customers’ requirements, thereby enhancing flexibility and eliminating unnecessary waste. At the same time, it extends the service life, saves costs, and reduces the workload for workers. Don’t worry about stopping the mill and adding steel rods every day – it even **increases production**. 1. Analysis of the broken rod phenomenon: (1) Causes: A. Material: internal porosity. Regarding the issues with steel billets in steel mills, only very large-scale mills are able to meet the stringent technical requirements involved, especially for those with a diameter of 70 mm or more. While most steel mills can produce billets of this type, their compression ratio and hardenability are low, meaning that their structure is not dense enough. B. Process: The internal internal stress has not been relieved. Bar breakage is like an explosion, occurring from within; the process of producing steel bars in steel mills is similar to inflating a balloon – it is necessary to relieve the internal stresses in order to prevent bar breakage. (2) Solution: A. Focus on the materials. a. Try to use materials from **super-large steel mills** ； b. The new alloy material independently developed by our company (Huamin Grinding Rods) was specifically created by industry experts in wear resistance from Tsinghua University and Dalian University of Technology, taking into account the conditions under which rod mills operate. It possesses excellent hardenability, and is produced by a **very large steel factory (under a confidential agreement). B. Processing technology: The steel rod processing technology developed independently by our company (Huamin Grinding Rods) has been granted a **patent**. It significantly improves the wear resistance of the steel rods, and breakage does not occur (we will replace them free of charge if they break). C. The size specifications can be adjusted flexibly; generally, the steel bars supplied by steel mills are 6 meters long. If you use 4-meter long bars, then the 2 meters that remain will be wasted. Our company (Huamin Grinding Rods) can produce bars to custom lengths. D. Our company (Huamin Grinding Rods) produces wear-resistant steel rods using new materials and processes, which extends their service life, reduces costs, and lessens the workload on workers. Don’t worry about stopping the mill and adding steel rods every day – it even **increases production**. 2. Regarding the hardness of the steel rod: The optimal hardness level is 45-50. If it is lower than this, the rod is too soft and not wear-resistant; if it is higher, it is too hard and brittle, making it prone to breaking ； Furthermore, in terms of manufacturing processes, domestic manufacturers can only achieve an HRC hardness of over 45 on the surface of the steel rod for a maximum of one centimeter; once that 1 centimeter is ground, the surface becomes identical to that of a round steel bar. Our company (Huamin Wear-Resistant Steel Bars) produces wear-resistant steel bars for rod mills in accordance with international standards. Moreover, thanks to our company’s proprietary manufacturing process (which has been patented), the overall performance of these steel bars is improved. For example, while ordinary steel bars have a surface hardness of HRC 45 and an internal hardness of HRC 10, our bars can achieve a surface hardness of HRC 50 and an internal hardness of HRC 25. 3. Differences between wear-resistant steel bars, ordinary steel bars, and round bars: Round bars are raw materials produced by steel mills; they are not finished products. Using them as steel bars for rod mills leads to various problems such as bar breakage and failure (with sharp ends at both ends). Their hardness is only 20, meaning they are not wear-resistant at all! Steel bars are produced through further processing of round steel; their surface hardness is 45-50, making the surface wear-resistant while the interior is not. Wear-resistant steel rods are the true steel rods for rod mills. Shandong Huamin Wear-Resistant Steel Rod Co., Ltd. Zhang Xun/Marketing Director Mobile: 13953147415 QQ: 549551716 MSN: huamin-steelball@hotmail.com Email: huamin.steelball@gmail.com Product catalog: http://www.steelrod.eb80.com/

Huamin Company produces 30,000 tons of steel rods for rod mills each year; it is the largest manufacturer of such steel rods in China, and its products are sold to more than 20 countries and regions around the world. Huamin steel rods are suitable for a wide range of users of rod mills and coal grinding mills, including quartz sand plants, mines, cement plants, power plants, silica sand plants, sand aeration facilities, coal chemical industries, concrete plants, and manufacturers of new building materials. Huamin wear-resistant steel rods differ from ordinary rolled round bars; they are specialized new types of wear-resistant steel rods designed for use in rod mills and grinders, having undergone special quenching and tempering treatments. Their wear resistance is 4-6 times that of ordinary steel rods, resulting in significant economic benefits. The steel rods currently in use in the market are produced by steel mills through rolling processes; they require low technical standards, have very poor wear resistance, and result in high consumption during use, leading to significant waste of ** resources. The main problems are as follows: 1. High wear: Due to low hardness and poor toughness, the consumption of round steel is very high, which in turn increases the workload and costs in the magnetic separation process, and even affects product quality. 2. Sharp ends at both sides: The sharpness of the steel rod’s ends is caused by various factors. The main reason is that the ends of the steel rod in a rod mill come into contact with the material for longer periods and over a larger area compared to the middle part, resulting in a longer effective grinding time at those ends. Once there is a noticeable difference between the condition of the ends and the middle part, such a steel rod is considered “failed,” as it can no longer perform effective grinding functions inside the mill. 3. Broken rod: The reason is porosity within the material. Regarding the issues with steel billets in steel mills, only very large-scale mills are able to meet the stringent technical requirements involved, especially for those with a diameter of over 70 mm. While most mills can produce such billets, their compression ratio and hardenability are low, meaning that their structure is not dense enough. Furthermore, since the internal stresses in the round steel bars are not relieved at the time of production, breakage occurs as if by explosion, starting from the inside. The process of producing steel bars in factories is similar to inflating a balloon; it is necessary to relieve the internal stresses in order to prevent the bars from breaking. 4. Bent rod: The main reason for bent rods is that round steel has very low hardness and is relatively soft; therefore, it easily bends when subjected to external forces such as impacts in a grinder. Once one of the rods bends, it disrupts the parallel arrangement of the steel rods inside the mill (the rods run parallel to each other within the mill, and as material passes through the gaps between them, it is ground into small particles or powder). In mild cases, this disruption leads to reduced efficiency of the mill; in severe cases, the rods may be thrown out of the mill, posing a threat to the safety of the workers and causing damage to the mill as well as other production equipment. 5. Low production efficiency, and the qualified products do not meet the requirements. This problem plagues many companies for various reasons, and steel bars also have a significant impact on it. For example, issues such as an unreasonable ratio between steel rods of different diameters, improper loading amounts, inadequate replacement of steel rods, and failure to remove defective rods in a timely manner. Our company has invested heavily in hiring various experts to study this product, with the aim of developing steel rods with higher wear resistance to replace the current consumable steel rods in use domestically. After years of research, production equipment for new types of alloy wear-resistant steel rods, as well as manufacturing processes for grinding rods made of different materials, have finally been developed. The wear resistance of this wear-resistant steel rod is 4 to 6 times that of a steel rod produced by rolling. Each year, it is possible to **save hundreds of thousands of tons, or even tens of millions of tons, of steel. Huamin’s wear-resistant rod production process: Communicate with the customer to understand their requirements for the steel rods, after which the material, model, and quantity are determined; large-scale steel mills supply the raw materials; the raw materials are inspected upon arrival at the factory; they undergo quenching and other heat treatment processes using the balancing method; further heat treatment steps are carried out; the products are inspected, stored, and finally the customer is followed up. The new type of wear-resistant steel rod produced using the equipment and processes developed by our company boasts a wear resistance 4 to 6 times that of round steel, addressing issues such as high wear, rod breakage, rod bending, and sharp ends at both ends. The size specifications can be adjusted to meet the customer’s requirements, enhancing flexibility and eliminating unnecessary waste. At the same time, it extends the service life, improves the production efficiency of the mill, reduces production costs, and lessens the workload on workers. This wear-resistant steel rod has the following features: (1) Its wear resistance is 1.5–2 times that of steel rods made by rolling, offering excellent wear resistance and helping customers save a significant amount of cost. (2) Produced using the latest methods, the dimensions can be adjusted to meet customer requirements, resulting in enhanced flexibility and the elimination of unnecessary waste. (3) It extends the service life, reduces costs, lessens the workload on workers, eliminates the need to worry about stopping the grinder daily to insert steel rods, and also **increases production. Introduction to key parameters: 1. Diameter: 18mm–110mm. 2. Length: 2.5m–7m. 3. Hardness: Can be adjusted according to customer requirements; for standard products, the hardness is between HRC45 and 55. 4. The raw materials are sourced from large domestic steel mills, and round bars with special chemical compositions can be manufactured as per customer requests. We welcome customers from home and abroad to visit our company for discussions. We are committed to providing high-quality products, timely delivery, competitive prices, and satisfactory service as the foundation for long-term cooperation. Zhang Xun, Shandong Huamin Steel Ball Co., Ltd. 13953147415 QQ: 549551716 Answers to common questions: 1. Analysis of broken or bent rods: (1) Causes: A. Material: internal porosity. Regarding the issues with steel billets in steel mills, only very large-scale mills are able to meet the stringent technical requirements involved, especially for those with a diameter of over 70 mm. While most mills can produce such billets, their compression ratio and hardenability are low, meaning that their structure is not dense enough. B. Process: The internal internal stress has not been relieved. Bar breakage is like an explosion – it starts from within. The principle behind steel mills’ production of steel bars is similar to blowing up a balloon; it is necessary to eliminate the internal stresses in order to prevent bar breakage. (2) Solution: A. Focus on the materials. a. Try to use materials from **super-large steel mills** ； b. The new alloy material developed independently by our company (Huamin Grinding Rods) was specifically created by industry experts in wear resistance from Tsinghua University and Dalian University of Technology, taking into account the conditions under which rod mills operate. It possesses excellent hardenability, and is produced by a **very large steel factory (under a confidential agreement). B. Treatment Process: The steel rod treatment process developed independently by our company (Huamin Grinding Rods) has been granted a **patent**; it significantly improves the wear resistance of the steel rods and prevents breakage. C. Dimensions: The specifications can be adjusted flexibly. Generally, the steel bars supplied by steel mills are 6 meters long; if you use 4-meter long bars, then the 2 meters that remain will be wasted. Our company (Huamin Grinding Rods) can produce bars to custom lengths. 2. Hardness analysis of wear-resistant steel rods: The optimal hardness for these rods is between 45-50; values below this range result in the rods being too soft and not resistant to wear, while values above this range make them too hard and brittle, prone to breaking ； Furthermore, in terms of manufacturing processes, domestic manufacturers can only achieve a hardness of HRC 45 or higher on the surface of the steel rod over a depth of up to one centimeter; beyond that depth, the hardness is the same as that of plain steel bars. Our company (Huamin Wear-Resistant Steel Rods) produces wear-resistant steel rods for rod mills in accordance with international standards. Moreover, thanks to our proprietary manufacturing process (which has been granted a **patent**), the overall performance of these steel rods can be improved. For example, while ordinary steel rods have a surface hardness of HRC 45 and an internal hardness of HRC 10, our rods can achieve a surface hardness of HRC 50 and an internal hardness of HRC 25. 3. Differences between wear-resistant steel rods, steel rods, and round bars: Round bars are raw materials produced by steel mills; they are not finished products. Using them as steel rods for rod mills leads to various problems such as rod breakage and failure (with sharp ends at both ends). Their hardness is only 20, meaning they are completely not wear-resistant! Steel bars are produced through further processing of round steel; their surface hardness is 45-50, making the surface wear-resistant while the interior is not. In conclusion, wear-resistant steel rods are the true steel rods suitable for rod mills

This post was last edited by banyechan on 2012-9-24 at 14:43. I have a client who is using a rod mill of type 2130; the particle size of the feed material is 8 mm, and the particle size of the output material ranges from 20 to 120 mesh. Could you please provide me with the appropriate ratio for the steel rods used in this rod mill? Thank you! My contact information is: Mr. Chen, Phone: 13553180285

Brother, you’ve come to the right person. The proportions in the coal chemical industry are basically fixed: diameter: 55/65/75 mm, ratio: 3:4:3. I hope this can help you; I specialize in producing steel rods and grinding rods for coal mills, with a hardness of HRC45-55, in custom lengths, after heat treatment