How To Choose Conveyor Structure

Like how the chassis of an automobile helps offer ruggedness, durability and smooth driving, the structure of a conveyor largely performs a similar role.

It doesn’t matter what industries your conveyor is servicing – from sand and gravel to silver, salt, trona, potash, copper or coal – the structure is important and cannot be taken for granted.

Selecting The Right Conveyor Structure

To give you a sense for the importance of conveyor structure, we’ve put together this post discussing the main types of structure and the factors that need to be evaluated in selecting the right one for your underground mining application.

Types Of Conveyor Structure

Before we get into some of the specific considerations for selecting the right conveyor structure for your application, it’s worth delving a bit into the main types of structure that is on the market today.

The three main types of conveyor structure include:

  • Rigid rail
  • Catenary
  • Wire rope

Rigid Rail

Rigid rail conveyor structure is considered to be very durable. It is typically made of steel and available in two different versions: floor mount and roof mount.

Additionally, it is typically available in either a single beam or a box frame design. The idlers are either bolted or clamped onto the frame, and this types of structure is available in belt widths up to 72 inches. Channel stringer can be either bolted or pin and cuffed together.

Aside from their durability, installation of rigid rail conveyor structure tends to be easy and convenient. On the other hand, rigid rail conveyor structure is more expensive than alternatives.


Arguably the biggest benefit of going with a catenary conveyor structure is that it’s portable. It’s fast and easy to install, and its portability is ideal for mining applications or projects that require the conveyor to be moved around to different sites on a regular basis.

It’s also a more affordable type of conveyor structure compared to rigid rail. On the flip side, catenary structure is less durable and lacks the rigidity for some conveyor applications.

Catenary structure is available in either floor or roof mount designs and is typically made of steel.

Wire Rope

Wire rope conveyors, or cable conveyor systems, are an economical option for transporting more non-demanding products or materials over long distances. Essentially, this type of structure works as idlers are connected to wire rope rather than the steel frames of catenary and rigid rail.

Wire rope is an affordable structure option, as well as portable, easy to set up and break down. Another key benefit is that wire rope conveyor structure requires less maintenance due to fewer components used in manufacturing. Wire rope structure, like catenary, is not as rigid and durable as the rigid rail design.

Factors To Consider When Selecting A Conveyor Structure

Now that we’ve gone over the main types of conveyor structure, there are various other factors that need to be weighed before making a decision.

Here’s a closer look at some of the most important considerations when choosing conveyor structure.

CEMA Rating

CEMA stands for the “Conveyor Equipment Manufacturers Association,” and like most industry associations, it has established a list of recommended ratings that professionals should follow when it comes to conveyor structure.

In this case, CEMA rating typically refers specifically to idlers. CEMA ratings are designed to dictate idlers that are suited for certain things, so the ratings are more so to pair idlers to particular applications.

For instance, CEMA B, C, and D rated rollers are best for applications that demand lower rotations per minute and are more desirable for lower tonnage operations. Alternatively, CEMA E and F rated idlers are ideal for heavy-duty applications or conveyors that work in demanding environments. When choosing your CEMA rating, it is best to not take a one size fits all approach because all conveyor systems are different. Considerations include conveyor speed, material density, belt weight, tonnage, loading section design, etc.

If you have any questions about what CEMA rating is right for you and your specific application, we’d encourage you to contact West River for additional assistance.

Tons Per Hour

This is another essential consideration, as it’s vital your conveyor structure is designed to work as productively as possible. If it’s not, then that’s money you’re losing on lost productivity.

Most conveyor manufacturers will make sure to include tons per hour (TPH) in spec sheets on their equipment. However, some may also list productivity in cubic feet or cubic meters per hour, which might require some measurement conversion to get a more accurate read.

Keep in mind that product density may impact TPH as well.


Naturally, speed is a critical part of meeting conveyor productivity requirements.

This is a measurement that’s typically expressed in feet per minute (FPM).

Spacing of Idlers

In order to mitigate belt sag and spillage, proper idler spacing is critical. Too far apart, conveyor systems won’t have the necessary support to move material efficiently. If idlers are closer together than required, cost may become an issue. The industry standard for most underground applications is five feet of separation on troughing idlers and ten feet of separation on return idlers. However, these parameters are not set in stone because each application is different.

Type Of Material

Most conveyor structure these days are made from heavy-duty steel, which helps them to stand up to demanding environments. Factors to consider when choosing material finish are the corrosiveness of the material being transported and the environment in which the conveyor system operates. West River’s structure, unlike most other structure on the market, is powder coated to make it more durable and resistant to corrosion.

Make sure to check the material and any finishing that is done on the structure for an accurate depiction of what to expect.

Don’t hesitate to consult with West River to find the right solution.

Choosing Conveyor Structure

In order to select the right conveyor structure, consider the needs and requirements of your underground mining application. By assessing the aforementioned factors, you can make a decision on the best equipment for reliable and efficient system operation.

West River designs and builds conveyor structure for all types of applications.

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