Fast quality inspection of hemp to provide basis f

2022-08-22
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The rapid quality inspection of hemp raw hemp provides the basis for production

Abstract: the quality inspection of hemp raw hemp adopts the method of "one look, two touch, three shake and four pull", which can quickly test the quality of hemp raw hemp and carry out quality acceptance of hemp raw hemp. It can also provide a basis for production, process, consumption, economic benefits, etc

key words: Cannabis; Raw hemp; Quality; Inspection

0 preface

cannabis: alias hemp, Quebec hemp, Lu hemp, white hemp, hemp, flower hemp, seed hemp, etc. It is an annual herb of cannabis family and cannabis genus

scientific name: cannabissativa, l

English Name: hemp, commonhemp or truehemp

the country that produces the most cannabis in the world is Russia, followed by China, France, Italy, gb/t18477 (2) 001 "unplasticized polyvinyl chloride (PVC-U) double wall corrugated pipes for buried drainage" and other countries

the main producing areas of cannabis in China are: Shanxi, Shandong, Henan, Hebei, Anhui, Gansu, Yunnan, Sichuan, Heilongjiang and other provinces

the excellent varieties of hemp and twine in China mainly include Lu hemp in Shanxi, white hemp in Yuxian County, Hebei, hemp in Laiwu, Shandong, and twine in Gansu

the yield of Quebec hemp in Gushi County of Henan Province and Lu'an City of Anhui Province is the largest

hemp fiber not only has the common characteristics of other hemp fibers, such as straightness and smoothness, moisture absorption and permeability, fast heat dissipation and moisture dissipation, durability, ruggedness and boldness, but also has special functions such as antibacterial and mildew inhibition, sound insulation, anti-static, anti ultraviolet, no itching and so on. Therefore, hemp fiber textiles are increasingly favored by people

1 hemp raw hemp

hemp raw hemp: hemp bast used as hemp textile raw material (referred to as hemp bast)

hemp raw hemp can be divided into two categories according to different processing methods (retting)

hemp (water cut hemp): hemp bast stripped after water retting, washing and drying

Quebec hemp (dry stripped hemp): it is stripped after drying, stacking and re exposure. 3. Please place hemp bast on a solid bottom cabinet or concrete foundation when installing this experimental machine

due to the different origin, variety, climate, soil and processing (retting) methods, the original hemp has great differences in appearance, color, luster and quality, and the quality is even more different

for hemp textile enterprises, the quality of hemp raw hemp directly restricts the quality, grade, processing difficulty and economic benefits of hemp textile products. Therefore, the quality inspection of hemp raw hemp is crucial for hemp textile enterprises

2 rapid test method for the quality of raw hemp

based on 20 years of practice in the quality test of raw hemp, hemp degumming and combing spinning process, quality and technology, the author believes that in order to quickly and accurately identify the quality of raw hemp, we can follow the rapid test method of "one look, two touch, three shake and four pull"

2.1 one look

one look includes color, gloss, appearance, length, etc. Visual inspection is mainly used

look at the color: the color of hemp is bright white, yellowish white or light yellow, the variegation is bad, and black is the worst

look at the gloss: the hemp gloss is natural, soft and bright. If it is gray and lusterless, the quality will be poor

look at the appearance: look at the appearance mainly depends on the peeling quality. The peeling quality of hemp skin is neat and smooth. If the peeling of hemp skin is messy and rough, the quality will be poor

look at the length: under the same other conditions, the quality of hemp with long bast length is better than that with short bast length

2.2 second touch

feel the elasticity and softness of the hemp skin by touching it with your hand. The hemp skin is soft, elastic, and has no hard skin or lump. Otherwise, the quality will be poor

2.3 three shakes

hold the root of the hemp bundle and shake the hemp bundle gently. If the hemp peel rustles, it indicates that the moisture content of the hemp peel is moderate, which can be stored and is not easy to mildew. 10. Specification of constant pressure servo pump station: 90l/min. On the contrary, it means that the hemp skin has high water content, is easy to mildew, and is not suitable for storage

when shaking the hemp bundle, less impurities (including hemp shavings, hemp bones, sand, dust) are shaken off, which means that the hemp skin contains less impurities and is of good quality. On the contrary, it means that the hemp skin has large impurities and poor quality

2.4 four pull

the strength of hemp can be judged by pulling the hemp skin with both hands. The quality of strong tension is good, on the contrary, the quality of small tension is poor

3 conclusion

through the four step rapid test of "one look, two touch, three shake and four pull", the quality of raw hemp can be basically judged, and whether it can be purchased and used can be decided

if you want to further understand the details of other quality indicators of hemp raw hemp, you can carry out chemical system analysis and physical property test of hemp raw hemp

chemical system analysis: it mainly includes quantitative analysis of the contents of total gum, cellulose, hemicellulose, lignin, pectin, fat wax, ash and so on

physical property test: mainly including fiber fineness (count) test and fiber relative strength test

by analyzing the total gum of raw hemp, we can pre judge the high and low rate of refined hemp after degumming and the difficulty of degumming

through quantitative analysis of the raw hemp chemical system (mainly including raw hemp cellulose, semi fiber, lignin, pectin, fat wax, ash, etc.), the degumming process of hemp with an accuracy of 0.5hr can be designed according to the number of chemical components. The consumption of degumming materials can also be calculated

by testing the physical properties of raw hemp (mainly including fiber fineness and relative strength), we can basically judge the spinning count of raw hemp

so far, the quality inspection of hemp raw hemp has been completed, which can provide a complete basis for the production, process, consumption and economic benefits of hemp raw hemp. (end)

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