Accurate Representative samples

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Quality control is critical to any operation.  If the samples taken aren't representative of the material coming out of the plant and being sold to customers this can result in major disputes that have a negative effect on a producers finances and reputation.

Getting accurate and representative samples off of conveyor belts can be tricky.

Issues with shoveling samples off of conveyors and load out bins include:

-Fines being left behind on the belt

-Material sloughing into the sample cut from above or below the area where the sample is being taken from

-Ensuring the sample cut is a consistent width across the whole belt

Issues with shutting down to take a sample:

-If a plant is abruptly stopped at full rate this may cause "pile ups" which during the plant restart can lead to spillage and belt spin outs

-If the plant rate is reduced before shutting down to sample this will likely cause the sample to not be truly representative of normal operating conditions

-Stopping and restarting a plant to take a samples increases the plant operators work load

RockPro samplers can be used at any time to take a sample without having to worry about shutting down.  The sample can be taken at full rates and will be representative of what the crusher is producing during normal operation.  

The A-1000 Sample Taker Accuracy Advantage:

-No fines are left behind

-The speed dial can be fine tuned to ensure the amount of sample collected is consistent and the preferred volume for the quality control staff who will be working with the sample.

-A cutting edge motor, encoder, and motion controller ensure that the sampler travels a dead steady speed through the material stream while collecting the sample.  

This ensures the sample will be 100% representative of the material exiting the plant.

The following is from Section 3 Aggregate Production and Stockpiling and Section 38 Sampling Gravel and Sand of the Alberta Transportation Technical Guideline.  Although this is obviously specific to Alberta Canada other jurisdictions likely have similar policies and guidelines. 

The guideline states:

-The Contractor shall provide safe and convenient means for accurately and representatively sampling each aggregate stream being produced during all screening, splitting and crushing processes. 

- Every precaution must be used to obtain samples that show the true nature and condition of the materials which they represent. Care must be taken to prevent contamination of the sample.  

-Getting a sample from a stockpile is not easy, and great care must be taken to obtain a truly representative sample.   

-There are also automatic belt sampling devices that have the advantage of sampling the aggregate without stopping the belt.   A representative sample of free falling aggregate consists of a cross-section of the entire flow of the material and is obtained using an automatic sampling device.