A well-designed radial stacker conveyor can bring efficiency and flexibility to your aggregate stacking process, while reducing your material handling costs. Is it worth the investment? We take a closer look at the costs of radial stacker crane conveyors.

Why choose a radial stacker?

Radial stacker conveyors offer an effective solution to a common stacking challenge: while stacking aggregates higher allows you to make better use of the space available, taller stackers also make it more difficult to work efficiently and safely, thus limiting productivity and potential revenue.

Radial stacker conveyors lift your aggregates up to the discharge point 40 feet above the stack, while also rotating to store material in a higher and wider arc. This allows you to stack more material in the space without having to reposition the equipment.

This can help to achieve:

Higher safety

Less material handling costs

Lower fuel and labour overheads

Reduced dust and waste

Increased profitability

With slopes of up to 20° and lengths of 150 feet or more, radial stackers can move some materials at speeds of up to 1,200 tonnes per hour (TPH) and can be built to handle a variety of common aggregates, including

Quarries

sand and gravel

Mining overburden

Frac sand

Salt and fly ash

Radial stackers can also be designed to

Telescopic: allowing the discharge head to be moved further from the loading point, increasing capacity by allowing larger piles to be stacked.

Portable: lighter weight construction for smaller portable units designed to be moved between temporary locations, such as road camps or wellhead supply points.

Portable Radial Stacking Conveyor

Elements of the radial stacker conveyor

The steeply inclined conveyor of a radial stacker is immediately recognisable in any location or yard, but there are several key components to any radial stacker system:

Assembly truss - the frame that supports the conveyor and the material load.

Radial landing gear - the moveable component that allows the stacker to rotate.

Conveyor Belt - designed according to the nature and characteristics of the material being handled.

Head - discharge point at the end of the conveyor

Tail - the point at which the material is loaded onto the conveyor

Drive unit - motor and reducer mounted in the head and connected to the discharge pulley

Cost drivers for radial stacker cranes

Radial stacker crane conveyors are complex, customised machines. The overall cost of a radial stacker crane is determined by several key cost drivers:

TPH - the tonnage per hour you need the stacker crane to handle

Elevation - the maximum height your equipment needs to be stacked to

Width - the width of the belt required

Material properties - the weight and density of the aggregates

Material properties - the specific properties of the material to be considered

Portability - do you need to be able to move your equipment to a new site?

Costs and options

Let's start with the conveyor belt itself and see how these considerations drive decisions about stacker design.

The conveyor belt

The maximum TPH your stacker crane needs to handle will determine the width of your stacker crane's conveyor belt and the speed at which it needs to run. Other key attributes in determining the speed and width of the conveyor belt include

The weight and density of the aggregates

Material sharpness, (see gypsum), particle size and cohesiveness

Moisture and dust levels

Conveyor belt grooving for efficient transport of different weights of material

Belts can be 24-60 inches wide and, depending on your material, can be of steel belt construction or multi-layer construction to withstand maximum load levels during loading.

Structure

The most important of these is the assembled frame that supports the conveyor system and its associated drives, reducers and idlers. The actual size of the structure is determined by the height that the radial stacker needs to serve, although this may be limited by the maximum gradient at which a given aggregate can be efficiently moved upwards by the available drivers.

Conveyor structures can measure anywhere from 30-150 feet or longer, allowing discharge heights of up to 40 feet and elevation ratings of 18-20°.