What is Rubber Conveyor Belt
Rubber Conveyor Belt is specifically a highly flexible industrial mechanical system used to move loads such as raw materials,/test products, or finished products. These are normally made of rubber compounds, natural or synthetic and they are provided with one or more layers of fabrics /steel to increase load bearing capacity.
The correct belt is selected according to the material being conveyed, belt width, belt speed, conveyor length, load, temperature, impact and required tensile strength.
How Is a Rubber Conveyor Belt Constructed?
A Rubber Conveyor Belt has three main parts:
1. Top Cover
The top cover comes into direct contact with the conveyed material. Its thickness and rubber grade are selected according to abrasion, impact, temperature and material characteristics.
Typical top-cover thicknesses include 3 mm, 4.5 mm and 6 mm, although the required thickness depends on the application.
2. Carcass
The carcass is the reinforcing structure inside the belt. Common constructions include:
- EP fabric – polyester in the longitudinal direction and polyamide/nylon in the transverse direction
- NN/Nylon fabric – nylon-based reinforcement
- Steel cord – used where very high tensile strength and long conveying distances require it
EP construction is widely used because it combines high longitudinal strength with relatively low elongation.
3. Bottom Cover
The bottom cover runs over the return rollers and pulleys. It protects the carcass from mechanical wear and contributes to the belt’s overall durability.
A common specification may be expressed as 6 + 2 mm, meaning a 6 mm top cover and 2 mm bottom cover. The actual cover thickness should be selected according to operating conditions.
Rubber Conveyor Belt Technical Specifications
The following parameters are normally considered when specifying a Rubber Conveyor Belt:
| Technical Parameter | Typical Specification / Range |
|---|---|
| Belt Width | 300–2000 mm or as required by conveyor capacity and design |
| Tensile Strength | 315–3150 N/mm, depending on carcass construction and belt rating |
| Carcass Construction | EP fabric, NN/Nylon fabric or Steel Cord |
| Common Belt Ratings | EP 315, EP 400, EP 500, EP 630, EP 800, EP 1000, EP 1250, EP 1600, EP 2000 and EP 3150 |
| Number of Plies | 2, 3, 4, 5 or application-specific multi-ply construction |
| Top Cover Thickness | Typically 3–6 mm; selected according to abrasion, impact and material characteristics |
| Bottom Cover Thickness | Typically 1.5–3 mm; selected according to conveyor configuration and operating conditions |
| Example Cover Construction | 6 + 2 mm, where 6 mm is the top cover and 2 mm is the bottom cover |
| Total Belt Thickness | Approximately 8–20 mm or as required by belt construction and application |
| Cover Grade | General-purpose, abrasion-resistant, heat-resistant, oil-resistant or fire-resistant |
| Operating Temperature | Application dependent; heat-resistant constructions are selected for elevated-temperature conveying |
| Elongation | Typically low elongation for EP constructions; exact value depends on carcass and belt design |
| Minimum Pulley Diameter | Application and carcass dependent; must be matched to belt construction and belt thickness |
| Belt Surface | Plain, Chevron or other application-specific profile |
| Belt Length | Manufactured according to conveyor layout and required endless or open length |
| Typical Applications | Mining, cement, stone crushing, aggregates, power plants, steel plants, ports and bulk material handling |
What Does EP Mean in a Conveyor Belt?
EP refers to the fabric carcass construction in which polyester provides longitudinal strength and polyamide/nylon provides transverse strength.
For example, an EP 500 belt represents a nominal tensile-strength class of approximately 500 N/mm. Other commonly used ratings include EP 315, EP 400, EP 630 and higher, depending on belt construction and manufacturer.
The required tensile rating should be determined from conveyor tension, belt width, conveying distance, material load, incline and operating conditions rather than selecting the highest available rating.
How to Select the Right Rubber Conveyor Belt
The correct belt depends on the complete operating condition.
Material Characteristics
Check whether the conveyed material is:
- Abrasive
- Sharp-edged
- Heavy or high-density
- Fine or dusty
- Hot
- Oily
- Chemically aggressive
Abrasion and impact conditions directly influence the required cover compound and thickness.
Belt Width and Capacity
Belt width must be suitable for the required conveying capacity, material characteristics and troughing arrangement.
The belt must also match the conveyor’s:
- Idlers
- Pulleys
- Skirting
- Belt cleaners
- Loading points
Incorrect width or inadequate load support can contribute to spillage, edge wear and tracking problems.
Tensile Strength
The required tensile rating depends on conveyor tension and operating conditions.
Higher-strength belts are generally considered for conveyors carrying heavier loads, longer distances or higher tensions. The belt rating should be selected through proper conveyor design calculations rather than simply choosing the highest available rating.
Frequently Asked Questions
1. What is a Rubber Conveyor Belt?
A Rubber Conveyor Belt is a continuous reinforced belt used to transport materials. It generally consists of rubber covers surrounding a reinforced carcass made from fabric or steel cord.
2. What is EP in a Conveyor Belt?
EP means polyester in the longitudinal direction and polyamide/nylon in the transverse direction of the belt carcass. EP construction provides high tensile strength with relatively low elongation.
3. How is Rubber Conveyor Belt strength measured?
Belt tensile strength is commonly expressed in N/mm, representing the nominal breaking-strength class per millimetre of belt width. The required rating depends on conveyor tension and design conditions.
4. What determines Rubber Conveyor Belt cover thickness?
Cover thickness depends mainly on material abrasiveness, impact, temperature, operating conditions and expected wear. Top and bottom covers may have different thicknesses.
5. How do I choose the right Rubber Conveyor Belt?
Consider the material, capacity, belt width, speed, conveyor length, belt tension, temperature, impact, abrasion, cover grade and carcass construction. For a replacement belt, the existing belt specification and conveyor design should also be checked.
Choose the Right Conveyor Belt
The right Rubber Conveyor Belt should be specified from the actual conveyor operating conditions rather than from belt size alone.
For complete belt options and application-specific configurations, explore CHERRY Conveyor Belts.