VRM Roller
One-stop service covering design, process and manufacture
Processing weight: 20-132T
Applicable industries: cement, building materials, power, metallurgy, etc.
Main Materials: ordinary carbon steel, silicon manganese steel.
Size: customization
VRM rollers or grinding rollers are the main grinding components of cement vertical mills, usually consisting of multiple (usually 2-6) grinding rollers. They rely on their own weight and the pressure of the hydraulic loading system to crush the material into fine powder.
As a professional vertical mill parts manufacturer, we focus on providing high wear resistance, high strength, and long life cement vertical mill rollers, which are widely used in cement, slag, coal, raw material preparation, and other vertical mill equipment. Our VRM rollers use an advanced casting process and wear-resistant technology to ensure excellent performance under extreme conditions.
The main functions of VRM roller are as follows:
- Rolling and crushing of materials: The rotating belt of the grinding roller on the grinding disc compresses and shears the materials, achieving the grinding process.
- Ensure grinding uniformity: Multiple grinding rollers work together to ensure that the material is evenly distributed throughout the entire grinding disc, improving grinding efficiency.
- Maintain stable mill pressure: The grinding rollers are regulated by a hydraulic system to adapt to different material characteristics and operating conditions.
High wear-resistant material, longer lifespan
- We offer three different materials of grinding rollers: High Cr Iron, Alloy Steel, and composite materials, which can be customized according to customer needs.
- High chromium cast iron grinding roller: HRC 55-65， Extremely high wear resistance, suitable for high load cement production lines.
- Alloy steel grinding roller: made of 42CrMo, 50Mn and other materials, with high toughness, suitable for high-speed and long-term operating conditions.
- Composite material grinding roller: using ceramic reinforced wear-resistant coating or bimetallic composite process to improve impact resistance and extend service life.
Advanced manufacturing technology, more reliable quality
- Precision casting+heat treatment optimization: The internal structure of the casting is uniform, stress is eliminated, and the risk of cracking is reduced.
- High precision machining: CNC machining ensures dimensional accuracy, reduces assembly errors, and improves equipment stability.
- Ultrasonic flaw detection: Ensure that the grinding roller has no casting defects such as pores, inclusions, cracks, etc.
Professional wear-resistant coating technology reduces maintenance costs
- Plasma Cladding Technology: A high hardness wear-resistant layer is formed on the surface of the grinding roller, with a thickness of up to 5-10mm.
- HVOF thermal spraying: using tungsten carbide (WC Co) coating to improve wear resistance and increase roller life by more than 30%.
- Laser Cladding: The wear-resistant layer is dense and has strong adhesion, making it suitable for ultrafine grinding applications.
Integrated solution, compatible with various brands of vertical mills
Our grinding rollers can be adapted to major domestic and foreign brands of vertical mills, including LOESCHE (Laiche vertical mill), Polysius (Polysius vertical mill), Gebr. Pfeiffer (Pfeiffer mill), Ube (Ube Ritsuro)
At the same time, we can also customize and process non-standard grinding rollers based on the drawings or samples provided by customers.
Manufacturing process of grinding table
1. Raw material selection
Grinding rollers need to withstand high pressure, high temperature, and long-term wear, so high-strength wear-resistant materials are usually used, such as:
- High Cr Iron: With high hardness (HRC 55-65) and good wear resistance, it is suitable for working conditions with strong wear such as cement, raw materials, slag, etc.
- Alloy Steel: such as 42CrMo, 50Mn, 35CrMo, etc., has high toughness and good wear resistance.
- Composite Materials: Using high chromium cast iron and ceramic reinforced coating to improve wear resistance and service life.
Different manufacturers will choose the appropriate material ratio based on the specific application requirements of the vertical mill.
2. Manufacturing process of grinding roller
Forging grinding rollers are suitable for alloy steel materials with high strength and toughness:
- Steel ingot heating: Heat the alloy steel ingot to 1100-1250 ° C to maintain good plasticity.
- Forging forming: Using forging equipment (such as hydraulic forging machines) for multiple passes of forging to improve the density of the structure.
- Machining: Rough machining is performed on the forged blank to ensure dimensional accuracy.
- Heat treatment: Adopting quenching and tempering treatment to improve hardness and toughness.
- Precision machining: including grinding and turning to meet the final assembly requirements.
3. Machining
The produced grinding roller blanks require further mechanical processing:
- Turning machining: Use a CNC lathe to machine the basic shape of grinding rollers, such as cylindrical surfaces, shaft holes, etc.
- Boring and drilling: Processing bearing seats, fixing holes, etc. to ensure assembly accuracy.
- Precision grinding: Improve surface smoothness, ensure the dimensional accuracy and dynamic balance performance of the grinding roller.
4. Wear resistant treatment (welding or spraying)
The wear resistance of the grinding roller is crucial. In order to extend its service life, high wear resistant materials are generally used for surface treatment through welding or thermal spraying technology
Plasma Cladding
- Weld a layer of wear-resistant alloy (such as Ni Cr Mo alloy or high chromium wear-resistant layer) on the surface of the grinding roller.
- The typical thickness is 5-10mm, and the hardness can reach HRC 55-65.
- Suitable for high load and high wear conditions.
Laser Cladding
- Using high-energy laser cladding metal powder to form a dense wear-resistant layer on the surface of the grinding roller.
- Compared to welding, the overlay layer is more uniform and has stronger bonding strength.
HVOF (High Velocity Oxygen Fuel Spraying)
Suitable for certain ultrafine grinding applications, it uses high-temperature and high-speed spray hard alloy (such as WC Co) coating to improve wear resistance.
5. Quality inspection
After production is completed, the grinding rollers need to undergo strict quality inspection to ensure compliance with usage requirements:
- Dimensional inspection: Use a coordinate measuring machine (CMM) to measure parameters such as the diameter, concentricity, and shaft hole accuracy of the grinding roller.
- Hardness testing: Use Rockwell hardness tester (HRC) or Brinell hardness tester (HB) to measure the hardness of the wear-resistant layer.
Ultrasonic testing (UT): detects whether there are cracks, pores, and other defects inside the casting. - Dynamic balance test: Ensure that the grinding roller does not produce uneven vibration during high-speed rotation.
6. Grinding roller assembly
Qualified grinding rollers need to be assembled:
- Install bearings: Use high-precision bearings to ensure smooth operation.
- Assemble the hydraulic loading system: Connect the hydraulic cylinder to achieve pressure control of the grinding roller.
- Overall assembly and debugging: Install the grinding roller onto the cement vertical mill and conduct a no-load or material test run to ensure stable operation.
7. Packaging and Transportation
As a large component, the grinding roller needs to be protected during transportation:
- Adopting rust prevention treatment to prevent rusting during storage and transportation.
- Packaged in wooden boxes or steel frames to prevent collision damage.
- Equipped with lifting structures for easy on-site installation.
why choose AGICO CEMENT?
1. Customized services to meet the needs of different working conditions
- characteristics of the material (clinker, slag, coal powder, etc.).
- Size customization: Supports the manufacturing of grinding rollers with various diameters (Φ 1000mm – Φ 3500mm) and weights (300kg-5 tons).
- Coating customization: Provide different wear-resistant layer treatment solutions to extend equipment life.
2. Fast delivery, reducing downtime
- Standard model grinding roller: always in stock, can be quickly shipped, reducing customer downtime.
- Non standard customized grinding rollers: Short production cycle, integrated control of casting, processing, and coating, with delivery time reduced by 20% -30% compared to the industry average.
3. On site installation and technical support
- Provide on-site surveying, assembly guidance, and debugging services to ensure accurate installation of grinding rollers and reduce vibration issues.
- Our professional technical team provides roller wear analysis and optimization solutions to help customers reduce operating costs.
4. Worry free after-sales service
- 18 months quality guarantee, free replacement for non-human damage issues.
- We provide remanufacturing services and can refurbish old grinding rollers, reducing customer replacement costs by over 30%.
- Global customer case support, serving over 300 cement plants both domestically and internationally, with a customer satisfaction rate of over 98%.
