Study on the performance criteria for coal mechanical sampler

The concepts of "Sampler Bias" and "Sampler Relative Precision" representing the sampler-self performance and their experimental methods were put forward.The conclusions are obtained through their theoretic analysis and test research: owing to the deduction of reference method error,B′ is decided by the sampler-self performance,and may better evaluate the sampler performance,and is scientific and more accurate than B;when the values of Vd and VRi/Vd are bigger,the difference between B′ and B is bigger;the relationship between P′L and PL is not certain,and P′L is independent on the coal used for test and sampling project,and is really representative for the sampler-self precision performance.