This issue collects the types of common mechanical defects in various cotton spinning processes to assist in the analysis of Uster evenness analyzer spectra, and can bring convenience to everyone in analyzing electronic evenness analyzer spectra.
01 Common mechanical defects in carding and combing processes
The carding doffer is eccentric, the large pressure roller has no tension, and the small pressure roller of the coiler is eccentric , no tension, small leakage and paste plugs at the carding bottom, etc. have an impact on the evenness CV value, spectrum, and curve graphs.
Poor wrapping of combed sliver joints, loose roller gears after combing, speed of nip, etc. also have an impact on the sliver and spectrum.
02 Common mechanical defects in the drawing process
The front top roller and front roller of drawing frame are eccentric, concave, bent, the front roller is broken, and the front skin The roller sleeve does not match the core, and the rear top roller is concave. The back roller knocked empty. After drawing flat lathes, wiping lathes, and adjusting gears, the gears are too tight or too loose, causing differences in the CV value of the entire lathe. Sometimes the axial movement of the gear also has a certain impact on the quality.
The mechanical components in the drawing process are more damaged and the mechanical waves generated are more obvious, especially when there are mechanical defects in the drawing process. After spinning into roving or spun yarn, it cannot be compensated by combination and drafting, and obvious mechanical waves will definitely be generated in the subsequent processes.
03 Common defects in the roving process
The front roller and front top roller in the front area of the roving are eccentric, bent, and concave. The pin rod under the roving is bent, the I-frame moves and the roving rusty roller. The meshing between gears is too tight or too loose. The spindle foot gear is beating and loose, and the roving clamp is too large or too small. Spinning without apron. These mechanical waves caused by defects in mechanical components occur more frequently, while draft waves caused by improper craftsmanship occur less frequently.
04 Common mechanical defects in the spinning process
Spinning front top roller, front roller, middle roller, middle top roller, rear roller and rear top roller eccentricity , bent, concave; the upper and lower apron of the spinning yarn is damaged or there is no lower apron; improper post-processing (referring to acid treatment) causes the top roller of the spinning machine to rust; the opening of the cotton collector is too large or too small. Rolling, poor meshing of light and heavy gears and bridge gears, etc., will have a direct impact on the quality of the next process, resulting in yarn defects.
05 Special Examples
The special examples are difficult problems that textile factories often encounter. Common problems include raw material problems, such as excessive lint content, super long fibers of polyester, and characteristic mechanical waves at 4cm in the spectrum of viscose fiber rovings, etc. Mechanically, there are the back-spun roller roller knocking, roller torsional vibration, drawing frame light and heavy gear supporting foot bearing knocking out, coil effect, etc. These problems have a serious impact and directly cause large-scale yarn defects in textile factories
06 Common mechanical defects in electrostatic spinning, friction spinning, and rotor spinning
1 .Electrostatic spinning: fiber winding electrodes; fiber winding on licker-in rollers, and cotton pipe hanging clothes.
2. Friction spinning: The condition of the semi-finished product is poor, the process channel is hanging, the holes of the dust cage are clogged, the flow rate of the friction spinning dust cage is improper, and the distance between the friction rollers does not meet the process requirements.
3. Rotor spinning (air-jet spinning): impurities are embedded in the rotor, the process air suction channel is blocked, and the licker-in roller is damaged. </p
