Testing method for raw silk
This standard specifies the testing method of weight and quality for raw silk in skein or on cone.
This standard is applicable to raw silk with nominal size of 69 denier and below.
2Normative references
The following normative documents contain provisions which，through reference in this text，constituteprovisions of this standard. For dated references，subsequent amendments(excluding corrections)， or revi-sions， of any of these publications do not apply to this standard. However parties to agreements based onthis stardard are encouraged to investigate the possibility of applying the most recent editions of the norma-tive documents indicated below. For undated references，the latest edition of the normative document re-ferred to applies.
GB/T 3916-1997,Textiles-Yarns from packages-Determination of single-end breaking force andelongation at break
GB/T 6529 Textiles-Standard atmospheres for conditioning and testing
GB/T8170 Rules of rounding off for numerical value& expression and judgement of limiting values
GB/T 9995 Determination of moisture content and moisture regain of textile—Oven-drying method
3 Lot formation and sampling
3.1 Lot formation method
One lot is specified as raw silk from the same origin, with the same reeling technology on the samereeling machines and with the same specification.Each lot consists of 10 bales(about 60 kg per bale)or 20 cartons(about 30 kg per carton).When the quantity is less than 10 bales or 20 cartons, regardthem as one lot as well.
3.2 Sampling method
Take representative samples for weight and quality test during appearance inspection.lt is restrictedto take only one skein from each book or onlv one cone from each carton.
3.3Sample size
3.3.1 Samples for weight test
3.3.1.1 For raw silk in skein with a capacity of 16 cartons—20 cartons(8 bales—10 bales)as one lot:take 4 groups of samples from each lot, each group consists of 2 skeins, thus 8 skeins in total(3 skeins from edge of the book,1 skein from corner,4 skeins from middle).
3.3.1.2 For raw silk in skein with a capacity of 15 cartons or below(7 bales or below)as one lot: take2 groups from each lot,each group consists of 2 skeins, thus 4 skeins in total (2 skeins from edge,2 skeins from middle).
3.3.1.3 For raw silk on cone take 4 groups from each lot, one group consists of 2 cones, thus4 cones in total(one cone from each top and bottom layer respectively,2 cones from the middle).
3.3.2Samples for quality test
3.3.2.1 For raw silk in skein: take total 25 skeins(12 skeins from the edge of book,9 skeins from themiddle,4 skeins from the corner).
3.3.2.2 For raw silk on cone:take 20 cones randomly from cartons.
4Testing method
4.1Weight test
4.1.1Apparatus
a) Platform balance: with a resolution of 0.05 kg or better.
b) Weighing balance: with a resolution of 0.01 g or better.
c) Oven with a balance: with a resolution of 0.01 g or better.
4.1.2 Test procedure
4.1.2.1 Tare weight
Obtain outer package weight by weighing 2 bales or 5 cartons( including the fixing carton paper , waterproof paper using platform balance).
Obtain inner package weight by weighing wrap paper , ropes from 3 skeins or cone tubes,socks from10 cones selected at random using weighing balance.
