BS 6043-1.1:2002 pdf download

BS 6043-1.1:2002 pdf download.Methods of samplingand test for carbonaceous materials used in aluminium manufacture—Part 1: Electrode pitch—Section 1.1: Sampling.
C) Pour the molten pitch without turbulence, so as to avoid entrapping air bubbles. into an air-tight metal container, allowing It to solidify and seal the container.
d) Note any froth formation during melting in the sample repoli and, in such cases; retain a separate portion of the finely-divided sample, stored in a sealed air-tight container, for the determination of water content.
If a sample container is opened, it shall be securely closed again as soon as poss4e and any damaged sealing rings shall be replaced.
4.3 Sampling for the determination of water content of pitch in solid form
For bulk shipments of solid pitch. a series of spot samples shall be taken for determination of water content, either from the conveying system during charge or discharge, or Irom the hold or compartment, or lorry at the top, middle or bottom during charge or discharge. The individual samples shall be sealed immediately in air-tight containers and tested promptty to avoid loss of moisture.
4.4 Mass of laboratory and reference samples
The mass of the laboratory and reference samples shall be at least three times the amount required for testing and shall never be less than 1 kg unless otherwise agreed in accordance with an established quality procedure. The sample mass shall be included in the sampling report (see clause 10).
The minimum recommended sample mass is 2 kg.
4.5 Safety precautions
Comprehensrve safety instructions are given In Iso 3165. Attention is drawn in particular to me following.
— When sampling hot liquid pitch from large containers such as ships, road or rail tanks, the sampler shal closely follow the safety procedures laid down for that site or location. These procedures typically include protective equipment and guidelines on safe working practice.
— Avoid inhalation of pitch vapour and dust.
— Sampling from ships, road or rail vehicles shall be strongly discouraged when in motion or when motion is likely to begin.
4.6 Suspect consignment
A consgnmenl shall be considered suspect if:
a) a container is damaged or defective:
b) there is any doubt as to the nature of the contents of a container, for example because of the presence of an old label or incorrect markings;
c) there is evidence of an unexpected lack of uniformity;
d) there are obvious and unusual variations observed in the consignment.
Such samples shall be fully reported and shall not be regarded as acceptable without mutual agreement between the parties concerned.
NOTE As pitch is a supercooled liquid, some advantage is gained during crushing the sample and cleaning of apparatus by pre refrigerating the sample.
Any work applied to the sample (e.g. punning) results In heat generation. caking and consequent segregation of the sample.
Preparation of low softening point pitches is also possible under cryogenic conditions.
Each Incremental sample taken shall have a minimum mass of approxImately 1 kg and a preferred mass of 2 kg unless otherwise agreed in accordance with an established quality procedure. Large sampling errors may arise if the material being sampled Is .nhomogeneous and undm such circumstances, it will be necessary to Increase the sample size.
Special considerations will also apply if the quantity to be sampled is small (approximately It or less) or very large (approximately 1 000 t or more).
If the quantity ot material to be sampled is more than approximately it but less than approximately 100 t, then no fewer than 10 samples shall be taken to allow for the heterogeneity of the materiaJ, Refer to Table 1, The mass of each sample taken from quantities of it to loot approximately shall be between 0.5 kg and 1 kg, but shall be at least 20 times the mass of the largest particle.
In the case of large quantities not in containers, several iokg samples shall be taken. Trie procedure specified in 5.2.2 shall be used to determine the number of incremental samples that shall be taken to form the representative sample.
5.2 Sampling plan for large quantities of solid pitch
5.2.1 Large quantities of solid pitch in containers
The minimum number of items to be sampled is given in Table 2.
5.2.2 Consignment of solid pitch not in containers
Use Figure t to determine the number of 10 kg incremental samples required to represent me ioi or consignment
5.3 Practical procedures for taking samples of solid pitch
5.3.1 Coarse pitch (including pencil, rod, plate and similar-formed pitch)
5.3.1.1 General considerations
This type of material is ikely to show the greatest variation of composition within its container. Particular care shall therefore be taken in obtaining a representative sample. Larger samples are necessary for materials of large particle size or size range. A suitably sized scoop may be used for sampling, preferably of width at least six times the diameter of the largest particles. An open-ended or closed-end sampling spear (see Figures 2 and 3) may be used as atternative sampliig tools.