Hemp:
Hemp is a bast fiber that has been with us since the beginning of civilization. It’s shimmer like silver and gold. The cloth from these fibers becomes softer and more beautiful with age. Hemp fibers have been used in prototype quantities to strengthen concrete, and in other composite materials for many construction and manufacturing applications. A flow chart of hemp fiber spinning is given below.
Process Flow Chart of Hemp Fiber Spinning
Raw hemp
↓
Crad set
↓
Softenting
↓
Cutting
↓
Combing
↓
Tos
↓
Carding/Tentering
↓
Doubling and drawing
↓
Roving frame
↓
Dry spinning/Wet spinning
↓
Winding
Spinning of Hemp Fiber:
- Five drafts and doublings are required and after the passage of drafting and doubling. The manufacture slivers are pre spun roving yarns. According to the quality and the desired fineness, spun into hemp yarn by wet and dry spinning process.
- A hemp roving frame is similar to that of a flax tow roving frame. The hemp is coarser than flax.
- The rove produced is then boiled in caustic soda. So that it is refined and most of the yarn is bleached with H2O2 (Hydrogen Peroxide).
- Hemp yarn is produced by both the wet and dry spinning process.
- Wet spinning involves passing the fibers through a trough of hot water before being spun. This process ensures that the pectins are softer which in turn allows the greater drawing out and separation of fibers and producing fiber yarns.
- Dry spinning on the other hand is cheaper producing yarns through the different appearance and handle, which is coarser compare to that of wet spun yarn.
- Using the above-mentioned process 2 types of hemp yarn are produced namely long yarn and short yarn.
- The above preparatory process of hemp fibers includes considerable waste termed as the hurd.
Author of this Article: S. M. Hossen Uzzal Production Officer Monnu Fabrics Ltd. Manikgonj Email: uhossen@gmail.com