Belt Conveyor Cleaner Selection Guide : Scraper Material

1. Introduction

Why is Scraper Blade Material a Key Factor Influencing Cleaning Efficiency and Conveyor Belt Lifespan?

In modern production lines, belt conveyors are the core equipment for material flow. However, material residue after transport not only causes resource loss and on-site environmental problems, but may also trigger belt mistracking, and abnormal wear on rollers and equipment, thereby shortening the service life of the conveyor belt and leading to unexpected maintenance costs and downtime losses.

The belt cleaner is the most direct and important equipment for addressing this issue. Among all the components of a cleaner, the material selected for the scraper blade, directly determines its cleaning ability, durability, and compatibility with the conveyor belt.

Choosing an unsuitable material can lead to:

• Poor cleaning performance: It is difficult to handle materials with high humidity, high stickiness, or high abrasiveness.
   
• Conveyor belt damage: Overly hard materials or improper installation can accelerate belt wear, and may even scratch the belt.
   
• High-frequency replacement: Insufficient wear resistance leads to a shortened maintenance cycle, increasing labor input and downtime.

This guide aims to delve into the mainstream scraper materials on the market, objectively analyzing their characteristics, advantages, and application limitations to help you make the most suitable decision for your equipment.

2.In-depth Analysis of Mainstream Scraper Blade Materials

Currently, the most common scraper materials that directly contact the belt are mainly in two major categories: Polyurethane and Tungsten Carbide. Additionally, there are applications of rubber or alloy materials for special operating conditions.

1. Polyurethane (PU) - The Top Choice for Balance, Stability, and Versatility

Polyurethane is a polymer that, through formula adjustment, can have a wide range of physical properties, from soft to hard. Due to its outstanding comprehensive performance, it has become the most widely used scraper material today.

• Core Characteristics：
   
  • Good elasticity: It can maintain good contact with the belt surface, compensating for slight unevenness on the belt surface to ensure the scraping effect.
     
  • High belt compatibility: Compared to metal materials, PU has lower wear on the belt, which helps protect the conveyor belt.
     
  • Chemical resistance: It has good resistance to most weak acids, weak bases, and industrial oils.
     
  • High adjustability: Hardness (common Shore A 70-95), color (dual-color wear limit indication), and formula (such as adding wear-resistant or anti-static agents) can be adjusted according to application needs.
    
    
     
• Advantages：
   
  • Protects the belt: It causes minimal wear on the conveyor belt surface, making it especially suitable for new belts or applications with higher requirements for belt surface integrity.
     
  • Wide applicability: It can meet the cleaning needs for most materials, such as sand, gravel, coal, grains, and recycled materials.
     
  • Cost-effectiveness: The initial purchase cost is relatively reasonable.
     
  • Operational safety: The material is lightweight, and the modular design is convenient for installation and replacement.
     
• Usage Limitations and Considerations：
   
  • Wear resistance limit: For materials with high hardness and high abrasiveness (such as ore like slag, sinter, coke), the service life is shorter compared to tungsten carbide.
     
  • Temperature range: Choose a scraper with a suitable heat resistance temperature for the environment, from the standard 80°C to high-temperature resistant 150°C.
     
• Applicable Conditions：
   
  • A common choice for Primary Cleaner and Secondary Cleaner.
     
  • Suitable for conveying medium-to-low abrasive materials like sand, ore, coal, fertilizers, and wood chips, which fits the vast majority of sites.
     
  • Application scenarios that emphasize belt protection.

2. Tungsten Carbide - The Outstanding Choice for Severe Abrasive Conditions

Tungsten carbide is a metal-based composite material, known for its extremely high hardness and excellent wear resistance. The scraper blade typically uses a structure where a tungsten carbide tip is embedded in a steel base or hot-vulcanized onto rubber, to balance both wear resistance and structural strength.

• Core Characteristics：
   
  • High hardness: It has very outstanding anti-wear performance.
     
  • Edge retention: It can maintain the flatness and sharpness of the scraping edge for a long time, providing stable and efficient cleaning performance.
     
  • High temperature resistance: Compared to polyurethane, it can withstand higher material temperatures.
    
    
     
• Advantages：
   
  • Longer service life: When dealing with highly abrasive materials, its replacement cycle is longer than PU material.
     
  • Excellent cleaning performance: The cleaning effect is significant for dry, hard, or caked-on materials.
     
• Usage Limitations and Considerations：
   
  • Potential risk to the belt: When the installation angle is improper, the belt is already damaged, or it encounters external impact, the hard blade may cause scratches on the belt surface.
     
  • Higher initial cost: The material cost is higher.
     
  • Splice type restriction: It is strictly prohibited for use on belts with mechanical fasteners, as it may cause serious damage to the fasteners and the scraper, and may even tear the belt.
     
• Applicable Conditions：
   
  • Heavy-abrasion environments such as mines, quarries, cement plants, and steel mills, for conveying hard ore, clinker, and sinter.
     
  • Mostly used as a secondary or tertiary cleaner, where material impact is significantly reduced and the belt runs more stably.
     
  • Only for belts that use vulcanized splices.

3. Other Special Materials

• Rubber
   
  • Advantages: Soft texture, good conformity to the belt, especially for aging or worn old belts, and low cost.
     
  • Considerations: Lower wear resistance, wears out quickly, and the flatness of the edge is difficult to maintain, which reduces cleaning efficiency and leads to easy aging.
     
  • Applicable for: Conveying loose, low-adhesion materials, or as a transitional solution for old belts
    
    
     
• Ceramic
   
  • Advantages: Excellent wear resistance in some extreme abrasive conditions.
     
  • Considerations: High brittleness, extremely sensitive to impact, and expensive.
     
  • Applicable for: Only used in specific applications with extremely high abrasion but low impact.
     
• Specialty Alloy Steel
   
  • Advantages: Optimized for special chemical environments that require high temperature or corrosion resistance.
     
  • Considerations: Wear resistance is usually not as good as tungsten carbide, and the cost is higher.
     
  • Applicable for: Conveying high-temperature materials (such as fresh clinker) or corrosive chemical raw materials.

3.Quick Selection Comparison Table

4.Four Key Questions Before You Decide

Before you make your final material decision, you must evaluate the following four key questions:

1. What are the characteristics of the conveyed material ?
    
   • Abrasiveness: Is it a high-hardness ore or a low-hardness material? Abrasiveness is the primary indicator for choosing a wear-resistant material.
      
   • Moisture and stickiness: What is the moisture content and adhesion level of the material?
      
   • Temperature: Is the material in a high-temperature state?
      
2. What is the condition of the conveyor belt?
    

   • Splice type: Is it a smooth vulcanized splice, or a protruding mechanical fastener? This is acrucial prerequisite for evaluating whether a tungsten carbide scraper is suitable.
      

   • Belt speed: Do high-speed belts have higher requirements for the cleaner's dynamic impact and the material's heat resistance?
      
   • Belt surface condition: Is the belt in a new state or does it already have a certain degree of wear?
      
3. What is the installation position of the cleaner?
    
   • Primary Cleaner (at the head pulley discharge point): It withstands the largest material flow and impact, so it's usually recommended to choose high-elasticity polyurethane.
      
   • Secondary/Tertiary Cleaner (on the belt's return path): Material impact is greatly reduced, and the belt is more stable, making it an ideal position for installing scrapers with high-hardness materials like tungsten carbide.
      
4. What are your maintenance strategy and budget plan?
    
   • Are you focusing on reducing the initial purchase cost? Polyurethane is an ideal starting point.
      

   • Is the goal to extend the maintenance cycle and reduce long-term total operating costs? In the right conditions, tungsten carbide will show its long-term economic benefits.
      

   • What is the on-site maintenance personnel allocation? Materials with longer replacement cycles can effectively reduce maintenance frequency.

Conclusion:
There is no absolutely best material, only the most suitable choice for your specific conditions

Choosing the material for a belt cleaner's scraper blade is a technical decision that requires a comprehensive evaluation of application conditions.

• Polyurethane, with its excellent comprehensive performance, belt-friendly nature, and wide applicability, meets the needs of the vast majority of conditions, and is the most widely used after a comprehensive evaluation of conditions.
   
• Tungsten carbide, on the other hand, with its outstanding durability, becomes an efficient tool for enhancing production line stability in harsh conditions when professionally evaluated and correctly installed.

As a professional manufacturer of belt conveyor components, we at Junwei deeply understand the importance of precise selection for our clients' production lines. We hope this guide has provided you with valuable reference.

Phone: +886-07-8718126
Email: jw@roller.com.tw
Website: www.jimway.com.tw