Interpretation And Revision Of New Cotton Standards

In September 1, 2012, the new national standard of GB 1103 cotton fine staple cotton, which was jointly revised by relevant state departments, will be issued and implemented in September 1, 2013. The biggest change of new cotton standard is to upgrade cotton grades from "grade" to "color level". cotton Inspection will rise from traditional artificial sensory examination to machine testing, which can be said to be a qualitative leap from "human" to "machine", which is of great significance for the healthy development of China's cotton industry.

China's cotton grade inspection method, which has been used for 40 years, will soon become a history with the introduction of the new standard. The core content of the cotton standard reform is to change the grade to color level: cancel the grade, increase the color level, the quality index and inspection method of the rolling mill, modify the color characteristic grade to the color level, and make clear that the relevant clauses of the color level are mandatory clauses.

In view of the two different processing methods of cotton fine staple cotton, such as sawtooth processing and roller processing, the current cotton color grading system is built on the basis of sawtooth fine cotton, and it can not meet the requirements of the roller roller cotton inspection. Taking into account the retention of grade and color level quality indicators in a standard, it is not conducive to abolishing grades, but also results in confusion in standard standards and contents. Therefore, GB 1103 has been revised to two national standards, namely, GB 1103.1 "cotton fine wool cotton sawtooth processing" and GB 1103.2 "cotton fine wool cotton roller processing", among which sawtooth cotton standard adopts color grading index system, and the roller roller cotton standard still maintains grade index system.

　　 New standard to achieve "qualitative" leap

It is understood that at present, China Cotton market The fine cotton on top 98% is sawtooth cotton. So for the revision of the new standard, people pay more attention to the change of the content of GB 1103.1 "cotton fine wool cotton saw tooth processing" (hereinafter referred to as the new standard).

According to the information we know, the main changes of the new standard are: abolish the grade, increase the color level, the quality index and inspection method of the rolling mill, modify the color characteristic grade to the color level, and make clear that the relevant clauses of the color level are mandatory clauses; add the definition of "white cotton, light spot cotton, yellow dyed cotton, main color grade and quality of the rolling mill"; define the color level division, color grading diagram and color level physical standard; define the color level inspection sensory test and the large capacity fast cotton fiber tester; and define the classification of the rolling quality, the quality grading condition of the rolling mill, the quality reference index of the rolling mill, and the physical quality standard of the rolling mill quality.

　　除此之外，還明確了軋工質(zhì)量采取感官檢驗(yàn);修改了“公定重量”的定義;取消了“準(zhǔn)重、籽棉準(zhǔn)重衣分率”的定義和計(jì)算方法;明確了成包皮棉品質(zhì)檢驗(yàn)和重量檢驗(yàn)可以分開(kāi)抽樣、檢驗(yàn)、出證;修改了籽棉抽樣數(shù)量;明確將皮棉滑道抽樣修訂為成包前檢驗(yàn)抽樣;取消了逐包檢驗(yàn)時(shí)按檢驗(yàn)單元檢驗(yàn)含雜率的規(guī)定;明確將馬克隆值按GB/T 6498檢驗(yàn)時(shí)隨機(jī)抽取批樣數(shù)量的30%作為馬克隆值試驗(yàn)樣品修訂為對(duì)批樣逐樣測(cè)試馬克隆值;修改了籽棉和成包皮棉檢驗(yàn)項(xiàng)目、檢驗(yàn)順序和組批規(guī)則;明確了棉花質(zhì)量標(biāo)識(shí)由“棉花主體顏色級(jí)、長(zhǎng)度級(jí)、主體馬克隆值級(jí)”順序標(biāo)示;修改了成包皮棉異性纖維含量分檔的范圍值;增加了“斷裂比強(qiáng)度、長(zhǎng)度整齊度指數(shù)”分檔代號(hào);取消了“六級(jí)、七級(jí)棉花的長(zhǎng)度均按25毫米計(jì)，記為25.0mm”的限制。

　　 New cotton standard 14 terms and definitions are given. In addition to the original standard, in addition to the 6 terms of gross weight, net weight, seed cotton percentage, linen percentage, heterosexual fiber, foreskin cotton, foreign fiber content and hazardous materials, 7 terms were added, namely, color grade, white cotton, light spot cotton, light yellow cotton, yellow cotton, main color level, and rolling quality.

　　 Quality requirements are meticulous.

There are 11 quality indexes specified in the new standard quality requirements, namely, color level, mill quality, length, micron value, moisture regain, impurity content, fracture strength, length uniformity index, hazardous material (heterosexual fiber content), reflectivity and yellow depth. Color level, mill quality, length, micron value, fracture strength, length uniformity index and hazardous debris are indicators of cotton quality. Although moisture regain and impurity rate are quality indicators, the new standard is not "qualitative treatment", but "quantity processing", which is used to convert the fixed weight of cotton.

Color classification: according to the Yellow depth of cotton, the cotton is divided into 4 types: white cotton, light spot cotton, light yellow cotton and Huang Ranmian. According to the degree of shade and shade of cotton, the white cotton is divided into 5 grades, the lighter cotton is divided into 3 grades, the yellow cotton dyed cotton is divided into 3 grades, and the yellow cotton is divided into 2 grades, which are 13 grades. It is worth noting that the white cotton grade 3 is the color standard grade. The color level is represented by two digits, the first is the level, and the second is the type.

　 Color level code

Rolling quality: according to the roughness of the appearance of the lint, the number and type of defects, the quality of the rolling mill is divided into three grades: good, medium and poor. Good lint appearance is smooth, cotton is fluffy and uniform, fiber entanglement is low, fiber seed chips are few, neps are few, sterile seeds and broken seeds are few, silk, soft seed epidermis and stiff pieces are few. The middle grade lint has a smooth surface, a uniform cotton layer and a general degree of fiber entanglement. The appearance of uneven cotton lint is uneven, uneven cotton layer and high degree of fiber entanglement.

Length revision: the length limit for grade six and grade seven cotton is cancelled. The original standard stipulates that the lengths of six and seven grades of cotton are measured in accordance with 25 millimeters, and are recorded as 25.0mm. 28 mm is the standard length. The length standard of cotton handle length is determined according to the average length of the upper part of the cotton measured by the fiber fast tester. That is, the length of the cotton hand pull should be calibrated to the average length of the upper part of the cotton measured by the fiber fast tester.

Micron value: the new standard is divided into three grades and five files according to the value range of the micron value, and the B level is the standard standard of the micron standard.

　 Micronan rating grading table

Moisture regain and impurity rate: the new standard stipulates that the moisture regain of cotton is 8.5% and the moisture regain of cotton is 10%. The standard impurity rate of cotton is 2.5%. In the process of standard revision, Spin The department puts forward: "with the improvement of cotton processing technology, under the normal processing conditions, the impurity content of sawtooth cotton should be less than 2.5%, and the standard impurity rate is required to be revised". However, due to the lack of experimental data in this field, we need further investigation in the future, and enough data will be revised.

The relative strength of fracture: a comparative study on the fracture strength between China and the United States in 2000 by the Ministry of agriculture, the results show that the strength of cotton in China is comparable to that in the United States. Therefore, the reference standard of the United States cotton grading manual is put forward.

Grading and code for fracture specific strength

Length uniformity index: the length uniformity index is divided into high, high, medium, bottom and low 5 stalls, respectively, using U1, U2, U3, U4, U5.

　　 Length uniformity index

Harmful sundries: in order to effectively reduce the content of foreign fibers in cotton, the new standard puts forward stricter requirements on the contents of foreign fibers in foreskin cotton on the basis of GB 1103-2007. The data used in the classification are determined according to the data provided by some textile enterprises and the opinions of the departments concerned. The new standard divides heterosexual fiber content into four grades: "no, low, medium and high", and uses the first letter of the corresponding English word "N, L, M, H" as a code name. In addition, the new standard stipulates that the cotton processing unit should brush the mark of foreign fiber when the cotton braid is brushed.

　 Classification and designation of foreign fiber content in foreskin cotton

Promoting healthy development of cotton industry

The new cotton standard pays more attention to the internal quality of cotton. The index closely related to the actual production needs of cotton spinning enterprises is more fully reflected in the standard, including impurity rate, foreign fiber and short staple rate, which is more advantageous to cotton spinning enterprises. The promulgation and implementation of the new standard will change the traditional inspection method which used to rely on the sensory inspection of the inspectors. The cotton fiber tester with large capacity should be used to quickly test the cotton quality, and the grading standard of the cotton grade with color grade should be implemented so as to fully realize the instrument package inspection of the large package cotton foreskin, so as to realize the scientific and objective assessment of the cotton's internal quality.

The revision of New Cotton Standards involves many contents, regardless of whether the contents of the amendments are comprehensive, but it is certain that the contents of these modifications are summarized by the relevant organizations and enterprises in the industry for many years. The revised contents make up for the deficiency of the old standards, and are of great significance for further promoting the development of modern agriculture, meeting the needs of the development of modern textile industry, and promoting the healthy development of China's cotton industry.