Home>ASTM Standards>ASTM D6404-99(R2020) pdf free download

ASTM D6404-99(R2020) pdf free download

ASTM D6404-99(R2020) pdf free download.Standard Practice for Sampling Vegetable Materials Containing Tannin
5. Significance and Use
5.1 This practice provides standard procedures for obtaining representative samples of various materials used as a source of tannins for the tanning industry. 5.2 Procedures are described for obtaining representative samples of economical and convenient quantities from a lot, or sections of a lot, of material for examination and analysis so that agreement may be reached with regard to the extent of variation ofquality in different portions ofa lot and the average quality of the entire lot of material. 5.3 No directions for sampling, however explicit, can take the place of judgment, skill, and previous experience on the part of persons actually engaged in the sampling or the supervision of the sampling. These directions are intended to supplement that experience and, particularly, to serve as a guide in the selection of the method which is to be used, in common, by each of two or more contracting parties. 5.4 Tanning materials contain moisture in varying amounts, depending both on the nature of the material and on the climatic conditions, so that sampling must be carried out as quickly as is consistent with thoroughness in order to avoid changes in moisture content.
7. Quartering Samples
7.1 “Quartering” is a term applied to the following method of reducing the size of samples without impairing their representative quality. 7.1.1 All of the material, taken from the various containers or parts of the shipment of solid material being sampled, shall be immediately and thoroughly mixed on a square piece of 11 oz canvas. In the case of solid extracts, large pieces shall have been broken previously so as to pass a screen having round openings 1.27 cm (0.50 in.) in diameter. The pile shall be divided into four equal portions and quarters A and B shall be discarded as illustrated in diagram X of Fig. 2. The remaining two quarters shall then be re-mixed thoroughly and again divided into four equal portions and quarters C and D shall be discarded as illustrated in diagram Y of Fig. 2. This process shall be repeated until the mixture of any two remaining quarters of the sample be of sufficient size to secure the individual samples as specified below. The individual samples shall be obtained by thoroughly mixing the two remaining quarters and dividing the mixture into as many uniform sections as necessary, such that each section will be large enough to fill one of the required number of containers. All fine, powdery material in each section shall be completely removed with its respective section, whether the section is discarded or placed in a sample container.
9. Number of Packages to be Sampled
9.1 The number of packages to be sampled from any given lot of tanning material composed of solid, powdered or pasty extract, crude or manufactured tanning materials, in bales, boxes, bags, barrels, or similar packages, shall be as shown in Table 1. The samples shall be selected from as uniformly distributed parts of the lot as is possible at the time of weighing. 9.1.1 Where the shipment exceeds 10 000 packages, it shall be divided into as few, equal, sections (ofnot more than 10 000 packages each) as possible and each section shall be sampled and analyzed as ifit were an individual shipment. In such case, the mean of the analyses of the sections shall constitute the analysis of the shipment.
10. Number of Samples
10.1 In addition to the representative samples for submis- sion to the contracting parties, at least one extra sample shall be taken and held in reserve by the sampler, in case one of the regular samples is lost or damaged.

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