Re: Sampling

Posted on 4. Jan. 2002 - 12:07

Sampling is probably one of the most underestimated activities in industry, in terms of importance for product quality. It may seem obvious that any sample obtained has to be truely representative, but the techniques adopted ny may companies are usually random and lack repeatability. If you are looking at obtaining samples it is important that you have already assessed the propensity for your material to demix or segregate, in addition to carrying out an audit to understand the flow patterns (and hence discharge regimes) in your storage equipment. Once you have a full undertsanding of these factors you can begin to think about sampling, with a view to obtaining relevent data about the product. Without this information you will have a hard time obtaining a representative sample.



With respect to sample pre-treatment, I would assume that this refers to the intial sample size (or combined samples) which will be sub divided to give the final sample for analysis. Do not make the mistake of taking a single 100 gramme scoop and using that as your test sample.

As with all aspects of bulk solids handling, getting to know your material is a pre-requisite for any technical or operational undertaking.

Regards

Richard Farnish, Consulting Engineer

The Wolfson Centre for Bulk Solids Handling Technology, Univ. Greenwich, London

e-mail: r.j.farnish@gre.ac.uk

URL: http://www.bulksolids.com

ID&T
(not verified)

Re: Question About Sampling

Posted on 5. Jan. 2002 - 06:32

Dear mr Herbst

ID & Teknik, Denmark (id-teknik.com) is a company, delivering sampling components and systems.

I agree with mr Richard Farnish.

The most usual mistake in sampling is to small amount of sample material, in the main sample.

The amount is calculated, depending on the size of the load you must represent and the spread of the data of the material , if it is heterogenus.

We take out a large amount of sample material (tonnes pro hour)

and make a pretreatment- 1. homogenizing (crushing+mixing), 2. a dividing of the material to end up with a final sample size, depending on the wanted analysing.

Please contact me for further informations

tito garcia
(not verified)

Re: Question About Sampling

Posted on 16. Mar. 2004 - 08:30

Originally posted by mherbst

What is representative sampling of heterogeneous materials

and what is sample pretreatment?

What is important to check for statistical data analysis?

Who found the information best or sampling of industry cement ..?