Belt Samplers

Belt Sampling Systems are utilized to collect a representative sample from a moving belt, which establishes the commercial value of a bulk material or to allow the operator to track the efficiencies of the facilities process.

The bulk material industry utilizes two types of belt sampling systems: (1) the Rotary Sweep Sampler; and, (2) the Conventional Cross Stream Sampler. Both types of conveyor belt samplers have been proven to provide a bias free sample. In comparison, the Rotary Sweep Sampler has been the device of choice because it has a lower initial procurement cost, operational costs are much lower, and sample increment sizes are much smaller.

Since the Rotary Sweep Sampler has become the sampler of choice to the bulk material industry, 2-stage processing systems are typically utilized in most applications where further processing of the primary sample increments is required. The typical second stage of a 2-stage system includes a sealed primary sample receiving chute, primary belt feeder, sample crusher, secondary sampler, sample collector, and reject handling system.

The 3-stage sample processing system is very common when the sampling system of choice is a Conventional Cross Stream Sampler due to the large volumes of sample material collected by the primary sampler and the required reduction stages required to reduce the sample to a manageable size.

The Rotary Sweep Sampler 3-stage system is utilized when small sample lot sizes are being created in high volume operations.

PSI custom designs each sampling system per the clients specific requirements and can include options such as on-line nuclear analyzers, moisture/ash monitors, weigh scales, metal detectors, etc. into the turnkey scope of work.

All PSI Belt Sampling Systems are designed in accordance with ASTM standards D-7430 Standard Practice for Mechanical Sampling of Coal. PSI belt sampling systems are guaranteed to be free from bias and the client can rest assured that a representative sample is being collected.

 
 

Precision Samplers PSI 30th Anniversary Precision Brochure

 

Rotary Sweep Sampler

The PSI Rotary Sweep Sampler is custom designed to meet the client’s specific requirements. PSI has designed and installed the Rotary Sweep Sampler for belt sizes ranging from 12” up to 84” wide. The PSI Rotary Sweep Sampler is a compact modular design perfect for new installations and retrofitting to existing facilities. In most installations, the PSI Rotary Sweep Sampler is installed between two existing conveyor idlers and bolts directly to the conveyor frame. The sampler has two integral garland idlers which actually replace two of the existing conveyor rollers. The garland idlers contour the belt into the correct belt radius to insure the primary sample cutter extracts a full cross sectional increment. The heavy-duty design of the PSI Rotary Sweep Sampling System allows the sampler to perform under the most extreme temperatures and operating conditions.

For typical belt speeds and cutter cycle dwell times, the PSI Rotary Sweep Sampler cutter assembly is coupled and powered through the stream of material on the conveyor belt utilizing an electro-mechanical drive assembly. The electro-mechanical drive includes an electric motor, brake, and gear reducer. This drive configuration is typical for most Rotary Sweep Sampling System applications.

When the primary sampler application is for a high speed belt and/or the increment dwell time is low, PSI offers an optional hydra-static clutch configuration which allows the primary sampler cutter speeds to be increased and/or the frequency dwell time to be lower. This drive configuration includes a drive motor, hydra-static clutch/brake, and gear reducer coupled to the cutter assembly.

PSI evaluates each application and will recommend the correct drive configuration for the client.

84" Hydra-Static Rotary Sweep Sampler

 

Conventional Cross Stream Sampler

The PSI Conventional Cross Stream Sampler is custom designed to be an integral part of the main conveyor head chute which meets the client’s specific requirements. The Cross Stream sampler is typically installed in new applications where large primary sample increments are required or space limitations exist prohibiting the installation of a Rotary Sweep Sampler along the conveyor. The PSI Cross Stream Sampler is available with either an electro-mechanical or hydraulic drive mechanism.

72" Conventional Cross-Stream Sampler

 

2-Stage Sampling System

The 2-Stage Sampling System is the most common system arrangement. This arrangement includes a sealed primary sample receiving chute, primary belt feeder, sample crusher, secondary sampler, sample collector, and reject handling system.

The primary belt feeder feeds the primary sample increments to the sample crusher where the sample increments are typically reduced to a 4-mesh product. The product from the crusher is gravity fed to a secondary sampler which takes a secondary increment. The secondary increment is gravity fed to a save sample container. The reject handling system returns the reject to the main conveyor for most installations.

2-Stage Sample Processing System

 

3-Stage Sampling System

The 3-Stage Sampling System is typically utilized with the Conventional Cross Stream Sampler which produces a very large primary sample increment and requires an additional stage of processing to reduce the sample to a manageable size. This arrangement includes a sealed primary sample receiving hopper, primary belt feeder, secondary sampler, secondary feeder, sample crusher, tertiary sampler, sample collector, and reject handling system.

The primary belt feeder feeds the primary sample increments to the secondary sampler, the secondary sample increments are fed via the secondary feeder to the sample crusher where the sample increments are typically reduced to a 4-mesh product. The product from the crusher is gravity fed to a tertiary sampler which takes a tertiary increment. The tertiary increment is gravity fed to a save sample container. The reject handling system returns the reject from the secondary sampler and tertiary sampler to the main conveyor for most installations.

Tertiary Traveling Hopper Sample Machine

 

On-Line Analyzer Integration

PSI has prior experience with the three leading manufacturers of on-line analyzers and has the technical expertise to custom design the sampling system to incorporate an on-line analyzer into the scope of the sampling system installation.

On-Line Analyzer Integration