AS 1301.402:2019 pdf free.Methods of test for pulp and paper Method 402: Statistical monitoring of test systems for paper and paper board.
4 Principle
For a particular test, a series of randomized samples of reference material is prepared such that measurements can be made at a minimum of two, but preferably three, levels over the working range of the test scale. The reference material is as typical as possible in all physical respects of the material normally tested by the test system. The reference material is tested in accordance with the relevant Standard at appropriate intervals by the test system being monitored. The test results may be graphed on a chart that is used to judge the performance of the test system.
5 Selection of reference material
The reference material, grades and types of products shall be selected that are typical of the kinds of material which are normally tested by the test system or systems, and whose test values are distributed throughout the range of test values likely to be encountered.
At least two, but preferably three, reference materials of different test values shall be selected for a particular test. Where three are selected, their test values shall be in the low, medium and high sections of the working range. Where two are selected, one shall have a value towards the low end of the working range and the other towards the high end.
When grades and types of product are selected, the performance of the paper or paper board machine shall be monitored during the manufacture of each of the selected grades. A reel shall be chosen that was made in a period, not near the start or end of a making, during which the machine conditions were stable and from that part of the deckle where the cross direction (CD) variation in moisture, grammage and tests of interest is least.
NOTE As shrinkage of paper is greatest on the paper machine towards the edge, which affects some properties, a centre reel should be selected.AS 1301.402 download.