D01-01 Sample divider

The tool for sample preparation. For representative sampling of solid materials, the aggregate sample has to be further reduced by weight. Several methods for sample division are used such as

• method of quartering,
• method of riffling or
• various rotation dividers.

Quartering divider: 

Riffle-type divider:   

Rotary divider: 

• Quartering method
  • The aggregate sample must be placed on clean non-absorbent flat surface.
  • Using a shovel, or a suitable tool, according to the particle size of the sampled material, the aggregate sample is formed into the shape of the cone. All of the aggregate sample must be included including dust and fine particles to ensure that the divided samples are representative.
  • The top of the cone is then flattened and divided into four equal quarters using a quartering divider or a frame or tool with four boards set at right-angles which can be pushed down through the layer.
  • Two opposite quarters are then removed (ensuring all dust and other small particles are also cleared away each time); the remaining pair is then mixed and formed into a separate cone.
  • This process is repeated until the remaining quarters are of a suitable size to make up the final samples; the final samples should include any remaining dust or small particles.
• Mechanical dividers. Where available Boerner or multiple-slot (Riffle-type) dividers should be used. The bottom of the riffler is divided into a number of fine chutes alternately facing left and right. When a powdery or granular sample is poured into the device it passes through the chutes, falling equally into the trays below and creating two identical portions. As with the quartering method, the aggregate sample must be reduced until the remaining quantity is suitable to make up the final samples. The material to be sub-divided is poured into the top of a riffler device and the sample is divided into two equal portions. The procedure of dividing is repeated, discarding the portions from alternate slots, until a portion of suitable size is obtained.
• Rotary dividers. The material is fed to the rotating distributor which allows subdivisions into two or more portions. The divider permits a continuous dividing process producing representative portions.