CN108998867B - Production method of pure cotton yarn by adopting roving-spinning unit - Google Patents

Abstract

The invention discloses a pure cotton yarn production method adopting a roving-spinning unit, which realizes seamless connection of roving and spinning processes in the production process of pure cotton yarns by reasonable raw cotton selection and by adopting an automatic doffing roving frame, a full-digital compact spinning automatic doffing spinning frame and a coarse and fine spinning automatic conveying system, thereby realizing the continuous production of the roving and the fine yarns, greatly reducing the production labor, simultaneously reducing the influence of touch, friction, collision and the like on the finished yarns in the processes of conveying a roving barrel among operation processes and the like, reducing the labor and improving the working efficiency.

Description

Production method of pure cotton yarn by adopting roving-spinning unit

Technical Field

The invention relates to the technical field of spinning, in particular to a production method of pure cotton yarn by adopting a roving-spinning unit.

Background

At present, in addition to policy, environmental and cost impacts, the expensive and scarce employment has become a severe reality facing the textile industry. Due to the serious problem of shortage of labor, textile enterprises in some regions choose to stop production or stop production locally, and the development of the textile industry is seriously influenced. The popularization of the novel automation equipment such as blowing-carding units, drawing frame automatic creeling devices and the like which are widely applied in industry, in particular high-speed large package equipment, greatly reduces the labor of the fore-spinning process. At present, most of workers still concentrate on three procedures of coarse yarn, fine yarn and winding yarn, and the work intensity of yarn taking, yarn inserting and yarn conveying after doffing is high, the simple and repetitive work is more, and the labor personnel loss is fast. Therefore, the automation and continuous operation of the above-mentioned works require more and more urgent research on intelligent spinning techniques.

On intelligent thickness antithetical couplet can directly carry the spindle with the roving through transfer orbit, the roving end is connected with reserve roving, accomplishes the change of yarn. After the yarn is replaced, the whole emptying pipe is automatically pulled out, and the standby roving can be automatically configured in the whole process. The whole process can realize automatic doffing, empty tube insertion, yarn threading, full bobbin and empty tube exchange, yarn tail treatment and the like without manual intervention, workers only take charge of circulating joints and changing strips, the workload can be reduced by more than 70%, the working efficiency and the production efficiency are greatly improved, and the number of the monitors of the car stops can be doubled. At present, foreign thickness and thinness union and thin network union are widely applied, but the product price is high, which is more than 3 times of the price of domestic assembled thickness and thinness union, and technical blockade and market monopoly are implemented in China; the development performance in China is good after decades of years, but compared with international advanced equipment, the intelligent and continuous monitoring device has large gaps in the aspects of intellectualization, continuity level, online quality monitoring, equipment stability, reliability and the like.

Disclosure of Invention

The invention aims to provide a production method of pure cotton yarn by adopting a thickness-thickness combination, which realizes seamless connection of thickness and spun yarn processes in the production process of pure cotton yarn, greatly reduces production labor, reduces the influence of touch, friction, collision and the like on finished yarn in the processes of conveying a thick yarn cylinder among operation processes, reduces labor and improves working efficiency.

In order to achieve the aim, the invention relates to a pure cotton yarn production method adopting a roving-spinning unit, which is formed by pure spinning of a roving-spinning unit and a spinning unit through a roving process and a spinning process by adopting a roving-spinning unit intelligent integrated roving-spinning unit, wherein both the roving machine and the spinning unit have an automatic doffing function, natural cotton fibers are processed through the roving process to obtain roving full bobbin automatic doffing after pure cotton roving, then the roving full bobbin automatic doffing is transmitted to a spinning frame through a roving-spinning unit conveying system, then the spun yarn full bobbin automatic doffing is obtained after the spun yarn process is processed through the spinning process, then the spun yarn full bobbin automatic doffing is carried to a spooling process through manpower, and finally bobbin yarn is obtained; the cotton blend comprises 14.3% of micronaire with the ever-growing origin, 4.5% of maturity coefficient, 1.74% of maturity coefficient, 36.1mm of upper half length, 10.24% of short staple rate, 1.34dtex of linear density, 3.3% of impurity content cotton fiber, 14.3% of micronaire with the ever-growing origin, 4.5% of maturity coefficient, 1.62% of maturity coefficient, 36.4mm of upper half length, 10.26% of short staple rate, 1.34dtex of linear density, 2.9% of impurity content cotton fiber, 14.3% of micronaire with the ever-growing origin, 4.4% of maturity coefficient, 1.63% of maturity coefficient, 37.2mm of upper half length, 10.84% of short staple rate, 1.25dtex of linear density, 4.1% of impurity content cotton fiber, 14.3% of silver with the ever-growing origin, 4.5% of maturity coefficient, 1.73% of maturity coefficient, 36.6mm of upper half length, 9% of short staple rate, 9.9% of impurity content, 4.1.1.1.1% of cotton fiber, 4.3% of mature rate, 4.5% of macro-growing percentage, 4.4.4.4% of cotton fiber, 4.4.4% of mature rate, 4.4.4% of upper half length, 4% of mature rate, 4.3% of high density, Cotton fiber with impurity content of 3.1%, 14.3% of production area is the micronaire value of the honeysuckle flower 4.5, maturity coefficient of 1.73, upper half length of 36.6mm, short fiber rate of 10.32%, linear density of 1.35dtex, impurity content of 3.3% cotton fiber, 14.2% of production area is the micronaire value of Xinjiang ambiguin 4.4, maturity coefficient of 1.73, upper half length of 36.3mm, short fiber rate of 9.78%, linear density of 1.53dtex, impurity content of 4.6% cotton fiber; the following production equipment is adopted in sequence: model JWF1012, model 1012, reciprocating plucker → model TF27, bridge magnet → model FA103A, biaxial flow opener → model FA028-160, multi-chamber mixer + model FA109-160, three-licker picker → JWF0016C, foreign fiber sorter → model JWF1054, dust remover → model 119A, spark remover → cotton box → model JWF1211, cotton carding machine → model JWF1310, drawing frame → JWF1383 lap combiner → rise E86, automatic lap changing comber → model JWF1312, 1312B, automatic leveling and drawing frame → THC2015 type full-automatic doffing roving frame → coarse-link conveying system → model TH59 598J, four-roller accumulating spinning automatic doffing spinning frame → SMARO-E type automatic bobbin winder. The FA103A biaxial flow cotton opener is provided with a FA051A type condenser + TF2407A type condenser connecting device. The THC2015 type full-automatic doffing roving frame adopts an external independent doffing device, the doffing device comprises three mutually independent systems, namely a doffing system, an exchange system and a spinning system, the three systems are not interfered with each other and have strong independence, and the normal operation of the spinning system is not influenced by the maintenance and repair of the doffing system, so that the shutdown time is reduced, the production efficiency is improved, the full-automatic process flow of spinning, doffing and yarn changing can be realized, the doffing process is simple, the stability is good, and the reliability is high; the lower keel mechanism with two degrees of freedom is adopted, the lower keel respectively moves in the vertical lifting direction and the horizontal direction to respectively perform spinning and doffing actions, the exchange of the lower keel from the lifting bracket to the shifting-out supporting hand is completed through the super-descending of the lower keel during doffing, the integral transverse translation is carried out, and the requirements of special operations of doffing and inserting of the automatic doffing roving frame on the lower keel are met; a steel belt rotary doffing and pipe inserting mechanism is adopted, a motor drives an annular steel belt to rotate through a driving wheel, a hanging ingot fixed on the steel belt is rotated, the rotary purpose is achieved, automatic operation of full yarn taking and emptying pipe actions is realized, and further automatic doffing circulation is completed; the automatic exchange of full yarn and empty yarn is realized by adopting an empty and full yarn exchange mechanism of a pneumatic control mechanical device, the exchange of single-spindle empty yarn and full yarn can be completed within 20s, and the yarn changing time of 120 spindles in the whole row is less than 40 min; the interface operation of the process parameters is realized by adopting the automatic spinning-in control program which is designed independently, and the rotating speed of the bobbin is instantly increased when the spinning is performed automatically according to different spinning varieties and different spinning coefficients set in the touch screen, so that the automatic spinning-in success rate of different spinning varieties is ensured. The TH598J type four-roller negative pressure type integrated spinning automatic doffing spinning frame adopts an electronic drafting device, the drafting part of the whole machine totally uses 7 servo motors and 8 planetary reduction boxes, wherein, the front rollers of the left and right vehicle table surfaces are driven by two servo motors and two planetary reduction boxes at the tail of the vehicle, the middle rollers are driven by four servo motors and four planetary reduction boxes at the head of the vehicle and the tail of the vehicle, the back rollers are driven by one servo motor and two planetary reduction boxes at the tail of the vehicle, and the drafting multiple can be changed by changing the rotating speed of the motors, thereby being suitable for spinning different types of yarns; an active electronic lifting mechanism is adopted, the electronic lifting mechanism comprises a servo motor, a planetary reduction gearbox, a plurality of groups of lifting gear boxes and a multi-head screw, the multi-head screw type active lifting mechanism is adopted to replace the original lifting belt lifting mechanism, so that the steel collar plate and a yarn guide plate are stably lifted, the bobbin is well formed, and the bobbin is suitable for the normal unwinding of a bobbin winder at 1500 r/min; adopt digital single spindle monitored control system, through the pilot lamp that sets up a plurality of different colours to every single spindle and subregion, and adopt the real-time status of every single spindle of different scintillation modes reflection, the locomotive of every spinning frame and the position that the workshop is showing still can set up the display screen that shows multinomial parameters such as disconnected end quantity, broken end spindle number after doffing specially, make things convenient for managers to master the running condition of every spindle in workshop in real time, thereby realize carrying out comprehensive on-line monitoring to the production and the quality of every single spindle of spinning frame, main detection parameter includes: the method comprises the steps of detecting the drafting efficiency of each spinning frame in real time, and connecting all the machine tables simultaneously so as to obtain the information of production, quality and the like of each shift, thereby realizing the real-time management of production managers on each machine table; the production monitoring system adopting the integrated control and Internet of things technology, the field bus technology and the Ethernet technology are adopted, and based on hard software platforms such as an industrial touch screen computer, a programmable logic controller, a frequency converter, industrial configuration software and the like, the spinning production monitoring system is established so as to realize the functions of real-time monitoring, data acquisition and analysis, report generation and the like of spinning production, ensure the accuracy and timeliness of production field data acquisition required by the resource planning management system ERP, and realize the integration of enterprise internal management information and field control information; the modularized combination design of the whole spinning frame is adopted, the whole spinning frame is composed of three modules, namely a sub-frame head, a tail and a middle section, the middle section modules are all the same and are 48 spindles per module, all parts are leveled and connected by a level instrument during installation, 6 persons of a long spinning frame can finish the modularized combination design by only 3-4 days after the modularized design of the spinning frame is adopted, the assembly efficiency is improved by 50%, meanwhile, the connection between machines is ensured by positioning pins, the assembly accuracy can be improved by 5%, the installation time is greatly saved, the working efficiency is improved, the installation cost is reduced, and 8000 yuan can be saved for a single spinning frame; the negative pressure structure optimization design is adopted, the fluid mechanics and aerodynamic principle are utilized, the negative pressure redistribution is realized through the air channel structure optimization design, and the requirements of energy conservation and environmental protection are met. The conveying system in the roving-spinning unit conveying system adopts an intelligent system composed of a controller and a micro motor, when a roving full bobbin runs to a spinning frame through a conveying rail after the roving frame automatically doffs, the spinning frame moves the full bobbin to a position needing yarn changing through the intelligent system and the conveying rail, a handheld remote control system enables each bobbin to accurately stop at the position needing yarn changing, the roving full bobbin can be accurately conveyed to each spinning spindle, the whole process mainly adopts a photoelectric sensing and wireless remote control means, the whole yarn changing system is automatically controlled, the fixed point accuracy of roving conveying is enabled to exceed 99%, and therefore the purposes of reducing manpower and improving working efficiency are achieved; the roving type identification technology is adopted, roving conveying and empty bobbin conveying are achieved through conveying chains, an electronic tag is mounted on each conveying chain, different IDs are given to the electronic tags and serve as unique identifications of each conveying chain, card readers are mounted at a yarn changing mechanical arm of a roving machine, an entrance and an exit of an intelligent yarn warehouse and an entrance and an exit of each spinning frame, full yarns and empty bobbins of the whole roving and spinning system are identified and information is collected, an RFID advanced technology is adopted, a computer communication technology and a field bus control technology are combined, an RFID and a sensor network are used as cores, real-time tracking and remote monitoring of each part in the conveying process are achieved, and requirements of the roving are automatically optimized; the first-in first-out of full yarn in the yarn warehouse and the shortest storage time of roving in the yarn warehouse are realized; the automatic identification and automatic confirmation of yarn varieties and the automatic, continuous and digital control of roving spinning and conveying are realized, the requirements of small batches and multiple varieties of spinning mills are met, the correctness of yarn varieties can be ensured, and the accuracy of roving conveying fixed point can reach more than 99%; the single-spindle single-clear tail yarn clearing device is arranged in a roving-spinning unit track connecting an automatic doffing roving frame and a spinning frame, residual yarns on the surfaces of bobbins in track operation are processed in time, qualified empty bobbins are conveyed to a yarn warehouse, and roving-spinning unit exchange is carried out at any time by the automatic doffing roving frame. The device can supply the spindle quantity according to the fly frame, 1 to 12 spindle arbitrary combinations, and per two fly frames are equipped with an 8 spindle tail yarn clearing machine, under the prerequisite of not damaging the yarn fibre, can realize opening completely and recycle to the tail yarn to manufacturing cost and workman intensity of labour have been reduced, make the workshop to few recruitment or unmanned development.

The production process specifically comprises the following steps:

opening and picking: adopt "rationally join in marriage cotton, many packages are taken, the process principle who grabs frequently, strengthens mixing" frequently, in the design of process parameter, in order to guarantee resultant yarn quality, need fully open, the edulcoration to the raw cotton, improve the misce bene degree and the lap degree of consistency of raw materials, wherein JWF1012 type reciprocal plucker's process parameter is: the rotating speed of the cotton grabbing beater is 1000r/min, the descending distance of the cotton grabbing beater is 1.5mm, the distance of the lug extending out of the rib is 3mm, the walking speed of the reciprocating trolley is 16m/min, and the static pressure of the cotton outlet is 970 Pa; the technological parameters of the FA103A biaxial flow cotton opener are as follows: the first beater speed is 412r/min, the second beater speed is 424r/min, the static pressure at the cotton inlet is 180Pa, the static pressure at the cotton outlet is 400Pa, and the static pressure at the impurity discharging port is 600 Pa; the FA028-160 type multi-bin cotton mixer has the following process parameters: the pressure of the bin changing is 200Pa, the rotating speed of a cotton opening beater is 570r/min, the rotating speed of a cotton conveying fan is 1800r/min, and the static pressure at the air return pipe opening is 20 Pa; the technological parameters of the FA109-160 type three-licker-in scutcher are as follows: the rotating speed of the beater is 1420r/min, the speed of the trolley is 17m/min, and the grabbing depth is 2.2 mm; the technological parameters of the cotton box are as follows: the rotating speed of a cotton feeding roller is 400r/min, and the rotating speed of an opening beater is 784 r/min;

cotton carding process: the principle of small ration, medium gauge, low speed, less noil and small tension is followed, and the uneven weight rate, the short fiber rate and the cotton knot number of the raw sliver are reduced to relatively low levels as much as possible; the processing parameters of the JWF1211 card are: the raw sliver quantity is 25.74g/5m, the web drafting multiple is 1.3, the distance between a cotton feeding plate and a licker-in is 0.23mm, the distance between the licker-in and a cylinder is 0.25mm, the distance between a cylinder and a cover plate is 0.3mm, 0.25mm, 0.2mm, the distance between the cylinder and a doffer is 0.15mm, the sliver discharging speed is 88.27m/min, the cover plate speed is 260.08mm/min, the licker-in rotating speed is 996r/min, the cylinder rotating speed is 474r/min, and the doffer rotating speed is 26 r/min;

pre-drawing process: an JWF1310 model 1310 drawing frame is adopted, and the specific process parameters are as follows: the dry basis weight is 26.6g/5m, the number of combined yarns is 6, the mechanical total draft is 6.069 times, the actual total draft is 5.948 times, the front draft is 4.895 times, the back draft is 1.805 times, the front draft tension is 1.012N, the back draft tension is 1.042N, the sliver outlet speed is 840m/min, the roller center distances are 45mm and 48mm respectively, the roller diameters are 35mm, the rubber roller pressurization is 120N, 300N, 320N, 300N and the bell mouth diameter is 2.8mm respectively;

strip and roll procedure: JWF1383 lap-combining machines are adopted, and the specific technological parameters are as follows: the quantitative yarn winding amount is 68.81g/m, the doubling number is 20, the mechanical total draft is 1.508 times, the actual total draft is 1.4778 times, the main zone draft is 1.314 times, the pre-draft is 1.074 times, the rotating speed of a roller in a roll is 177.6r/min, the linear speed of the roller in a roll is 390.54m/min, the distance between rollers is 48mm, the rolling speed is 75m/min, and the feeding tension draft is 1.396 times;

combing procedure: the Lida E86 automatic lap changing comber is adopted, and the specific technological parameters are as follows: the doubling number is 8, the sliver ration is 21.02g/5m, the cylinder rotating speed is 380r/min, the cotton feeding rotating speed is 250 mm/clamp, the cotton falling rate is 18%, the roller gauge is 6mm, the cotton falling gauge is 10mm, the roll-to-feed roller gauge is 0.9614mm, the cotton feeding roller-to-separating roller gauge is 6.3420mm, the separating roller-to-table-board press roller gauge is 0.9976mm, the table-board press roller-to-fifth roller gauge is 1.0148mm, the loop bar press roller-to-front roller gauge is 1.057mm, and the loop bar cylinder-to-upper loop bar press roller gauge is 1.011 mm;

drawing: an JWF1312B type auto-leveling drawing frame is adopted, and the specific process parameters are as follows: the dry basis weight is 19.12g/5m, the number of combined yarns is 8, the mechanical total draft is 9.06 times, the actual total draft is 8.87 times, the front draft multiple is 8.118 times, the rear draft multiple is 1.5 times, the front draft tension is 1.038N, the rear draft tension is 1.022N, the sliver outlet speed is 840m/min, the roller center distances are 46mm and 52mm respectively, the rubber roller pressurization is 140N, 400N and 400N respectively, the bell mouth diameter is 3.4mm, the pressure bar adjusting ring diameter is 13mm, and the sliver outlet speed is 300 m/min;

roving: the roving process design mainly aims at improving the roving quality and achieves the purposes of stable elongation, small weight difference, uniform yarn levelness, compact structure and good forming, and a roving frame adopts the process principle of light quantification and heavy pressurization; the THC2015 type full-automatic doffing roving frame is adopted, and the specific technological parameters are as follows: the dry basis weight of the roving is 3.47g/10m, the mechanical total draft is 11.04 times, the actual total draft is 10.93 times, the calculated twist is 4.37 twist/10 cm, the roller center distances are respectively 38mm, 48mm and 55mm, the rotating speed of a front roller is 292.67r/min, the rotating speed of a spindle is 840r/min, the caliber of a front area condenser is 10mm, the jaw spacing is 5.5mm, and the twist coefficient is 85.16;

spinning: the TH598J type four-roller negative pressure type compact spinning automatic doffing spinning machine has the following specific technological parameters: the dry weight of the spun yarn is 5.37g/10m, the mechanical draft is 66 times, the actual draft is 64.68 times, the back zone draft is 1.14 times of the twist direction Z, the twist is 169.98 twists/10 cm, the twist coefficient is 400, the roller gauge is 41.5mm and 75mm respectively, the caliber of the condenser is 1.8mm, the type of the steel wire ring is 13/0, the type of the steel collar is MXKSA 2, the diameter of the steel collar is 36mm, the rotating speed of a front roller is 1485r/min, the rotating speed of a spindle is 20000r/min, and the jaw of a rubber ring is 2.5 mm.

According to the invention, through reasonable raw cotton selection and matching, the seamless connection of the thickness process and the spun yarn process in the production process of pure cotton yarns is realized by adopting the automatic doffing roving frame, the full-digital compact spinning automatic doffing spinning frame and the automatic coarse and fine spun yarn conveying system, so that the thickness continuous production is realized, the production labor is greatly reduced, the influences of yarn defects and hairiness on finished yarns caused by touch, friction, collision and the like in the processes of conveying the coarse yarn barrel among operation processes are reduced, the labor is reduced, and the working efficiency is improved.

Detailed Description

By 100^SThe production of the combed pure cotton yarn is taken as an example, the raw cotton is distributed and then sequentially processed by the processing procedures of an opening picking procedure, a cotton carding procedure, a pre-drawing procedure, a sliver lap procedure, a combing procedure, a drawing procedure, a roving procedure, a spinning procedure and a winding procedure to obtain the cone yarn, and the processing procedures sequentially adopt the following production equipment: model JWF1012, model 1012, reciprocating plucker → model TF27, bridge magnet → model FA103A, biaxial flow opener → model FA028-160, multi-chamber mixer + model FA109-160, three-licker picker → JWF0016C, foreign fiber sorter → model JWF1054, dust remover → model 119A, spark remover → cotton box → model JWF1211, cotton carding machine → model JWF1310, drawing frame → JWF1383 lap combiner → rise E86, automatic lap changing comber → model JWF1312, 1312B, automatic leveling and drawing frame → THC2015 type full-automatic doffing roving frame → coarse-link conveying system → model TH59 598J, four-roller accumulating spinning automatic doffing spinning frame → SMARO-E type automatic bobbin winder. The specific technological process and parameters are as follows:

(1) cotton blending

TABLE 1 Cotton-assorting table

(2) Opening picking

TABLE 2 plucker process

TABLE 3 biaxial flow opener process

Table 4 multi-bin cotton mixing machine process

Table 5 scutcher process

Table 6 cotton box

(3) Cotton carding

Table 7 cotton carding process design table

(4) Pre-coalescence

Table 8 card process design table

(5) Strip and roll

Table 9 cotton sliver lap procedure process design table

(6) Combing

TABLE 10 combing procedure Process design Table

(7) Drawing

Table 12 drawing process design table

(8) Rough yarn

Table 13 roving process design table

(9) Spun yarn

Watch 14 spinning process watch

The quality of the produced yarn was tested as follows:

TABLE 15 yarn Properties

Claims (11)

1. A production method of pure cotton yarn by adopting a roving-spinning unit is characterized by comprising the following steps: the method comprises the following steps of sequentially processing raw cotton through a processing procedure of an opening and picking procedure, a cotton carding procedure, a pre-drawing procedure, a sliver lap procedure, a combing procedure, a drawing procedure, a roving procedure, a spinning procedure and a winding procedure to obtain cone yarn, and carrying out pure spinning through roving and spinning procedures by adopting a roving and spinning combined intelligent roving and roving combined device after cotton distribution on raw natural cotton fiber, wherein both a roving machine for the roving procedure and a spinning machine for the spinning procedure have an automatic doffing function, the natural cotton fiber is processed through the roving procedure to obtain roving full bobbin automatic doffing after pure cotton roving, and then is transmitted to a spinning frame through a roving and spinning combined conveying system, and then the spun yarn full bobbin automatic doffing after the pure cotton spun yarn is obtained through the spinning procedure is carried to the winding procedure manually, and finally is processed to obtain cone yarn;

the roving process adopts a THC2015 type full-automatic doffing roving frame, the THC2015 type full-automatic doffing roving frame adopts an external independent doffing device, and the doffing device comprises three mutually independent systems, namely a doffing system, an exchange system and a spinning system; a two-degree-of-freedom lower keel mechanism is adopted, the lower keel respectively moves in the vertical lifting direction and the horizontal direction to respectively perform spinning and doffing actions, and the exchange of the lower keel from a lifting bracket to a shifting-out supporting hand is completed through the super-descending of the lower keel during doffing, so that the integral transverse translation is performed; a steel belt rotary doffing and pipe inserting mechanism is adopted, a motor drives an annular steel belt to rotate through a driving wheel, a hanging ingot fixed on the steel belt is rotated, the rotary purpose is achieved, automatic operation of full yarn taking and emptying pipe actions is realized, and further automatic doffing circulation is completed; an empty and full tube exchange mechanism of a pneumatic control mechanical device is adopted to realize the automatic exchange of full yarns and empty tubes; an automatic repiece control program is adopted to realize the interface operation of the process parameters;

the spinning process adopts a TH598J type four-roller negative pressure type integrated spinning automatic doffing spinning frame, the TH598J type four-roller negative pressure type integrated spinning automatic doffing spinning frame adopts an electronic drafting device, the drafting part of the whole machine totally uses 7 servo motors and 8 planetary reduction boxes, wherein, the front rollers of the left and right vehicle table surfaces are driven by two servo motors and two planetary reduction boxes at the tail of the vehicle, the middle rollers are driven by four servo motors and four planetary reduction boxes at the head of the vehicle and the tail of the vehicle, the back rollers are driven by one servo motor and two planetary reduction boxes at the tail of the vehicle, and the drafting multiple is changed by changing the rotating speed of the motors; an active electronic lifting mechanism is adopted, and the electronic lifting mechanism comprises a servo motor, a planetary reduction gearbox, a plurality of groups of lifting gear boxes and a multi-head screw; a digital single-spindle monitoring system is adopted, a plurality of indicator lamps with different colors are arranged for each single spindle and each subarea, and the real-time state of each single spindle is reflected in different flashing modes; the production monitoring system adopting integrated control and Internet of things technology realizes the functions of real-time monitoring, data acquisition and analysis and report generation of spinning production and the integration of enterprise internal management information and field control information; the modularized combination design of the whole spinning frame is adopted, and the whole spinning frame consists of three modules, namely a sub-frame head, a tail and a middle section, wherein the middle section modules are all the same and are 48 spindles per module;

the conveying system in the roving-spinning unit conveying system adopts an intelligent system which is synthesized by a controller and a micro motor, when the full bobbin of the roving is moved to a spinning frame through a conveying track after the roving frame automatically doffs, the spinning frame moves the full bobbin to a position needing yarn replacement through the intelligent system through the conveying track, so that the full bobbin of the roving can be accurately conveyed to each spinning spindle; the identification technology of roving varieties, full yarns and empty tubes is adopted, the conveying of the roving and the conveying of the empty tubes are realized by a conveying chain, the full yarns in a yarn library are firstly in first out, the storage time of the roving in the yarn library is shortest, the yarn varieties are automatically identified and automatically confirmed, and the automation, the continuity and the digital control of the roving spinning and conveying are realized; the single-spindle single-clear tail yarn clearing device is arranged in a roving-spinning unit track connecting an automatic doffing roving frame and a spinning frame, residual yarns on the surfaces of bobbins in track operation are processed in time, qualified empty bobbins are conveyed to a yarn warehouse, and roving-spinning unit exchange is carried out at any time by the automatic doffing roving frame.

2. The method for producing pure cotton yarn by using roving and spinning unit as claimed in claim 1, wherein the method comprises the following steps: the processing procedure adopts the following production equipment in sequence: model JWF1012, model 1012, reciprocating plucker → model TF27, bridge magnet → model FA103A, biaxial flow opener → model FA028-160, multi-chamber mixer + model FA109-160, three-licker picker → JWF0016C, foreign fiber sorter → model JWF1054, dust remover → model 119A, spark remover → cotton box → model JWF1211, cotton carding machine → model JWF1310, drawing frame → JWF1383 lap combiner → rise E86, automatic lap changing comber → model JWF1312, 1312B, automatic leveling and drawing frame → THC2015 type full-automatic doffing roving frame → coarse-link conveying system → model TH59 598J, four-roller accumulating spinning automatic doffing spinning frame → SMARO-E type automatic bobbin winder.

3. The method for producing pure cotton yarn by using roving and spinning unit as claimed in claim 1, wherein the method comprises the following steps: the cotton blend comprises 14.3% of a Mark clone value 4.5 with a yield of eternal, a maturity coefficient of 1.74, an upper half length of 36.1mm, a short staple rate of 10.24%, a linear density of 1.34dtex, a impurity content of 3.3% of cotton fibers, 14.3% of a Mark clone value 4.5 with a yield of eternal, a maturity coefficient of 1.62, an upper half length of 36.4mm, a short staple rate of 10.26%, a linear density of 1.34dtex, a impurity content of 2.9% of cotton fibers, 14.3% of a mark clone value 4.4 with a yield of eternal, a maturity coefficient of 1.63, an upper half length of 37.2mm, a short staple rate of 10.84%, a linear density of 1.25dtex, a impurity content of 4.1% of cotton fibers, 14.3% of a mark clone value of silver flowers, a maturity coefficient of 1.73, an upper half length of 36.6mm, a linear density of 9.9%, a impurity content of 4.1.1.1.1% of 4.3%, a new staple rate of 4.5, a yield coefficient of 4.3% of 1.3% of cotton fibers, a mature staple rate of 4.3%, a high density of 4.3% of a high half length of the same, Cotton fiber with impurity content of 3.1%, cotton fiber with 14.3% of production area, micronaire value of 4.5, maturity coefficient of 1.73, upper half length of 36.6mm, short fiber rate of 10.32%, linear density of 1.35dtex, impurity content of 3.3%, cotton fiber with 14.2% of production area, micronaire value of 4.4, maturity coefficient of 1.73, upper half length of 36.3mm, short fiber rate of 9.78%, linear density of 1.53dtex, impurity content of 4.6%.

4. A process for producing a pure cotton yarn using a roving-spinning unit according to claim 1 or 2, wherein: the opening and picking process sequentially adopts the following production equipment: JWF1012 type reciprocating plucker → TF27 type bridge magnet → FA103A type biaxial flow opener → FA028-160 type multi-chamber cotton mixer + FA109-160 type three licker-in picker → JWF0016C type foreign fiber sorter → JWF1054 type dust remover → 119A type Mars finder → cotton box, wherein the JWF1012 type reciprocating plucker has the following process parameters: the rotating speed of the cotton grabbing beater is 1000r/min, the descending distance of the cotton grabbing beater is 1.5mm, the distance of the lug extending out of the rib is 3mm, the walking speed of the reciprocating trolley is 16m/min, and the static pressure of the cotton outlet is 970 Pa; the technological parameters of the FA103A biaxial flow cotton opener are as follows: the first beater speed is 412r/min, the second beater speed is 424r/min, the static pressure at the cotton inlet is 180Pa, the static pressure at the cotton outlet is 400Pa, and the static pressure at the impurity discharging port is 600 Pa; the FA028-160 type multi-bin cotton mixer has the following process parameters: the pressure of the bin changing is 200Pa, the rotating speed of a cotton opening beater is 570r/min, the rotating speed of a cotton conveying fan is 1800r/min, and the static pressure at the air return pipe opening is 20 Pa; the technological parameters of the FA109-160 type three-licker-in scutcher are as follows: the rotating speed of the beater is 1420r/min, the speed of the trolley is 17m/min, and the grabbing depth is 2.2 mm; the technological parameters of the cotton box are as follows: the rotating speed of the cotton feeding roller is 400r/min, and the rotating speed of the opening beater is 784 r/min.

5. A process for producing a pure cotton yarn using a roving-spinning unit according to claim 1 or 2, wherein: the carding process adopts an JWF1211 type carding machine, and the process parameters are as follows: the raw sliver dry weight is 25.74g/5m, the web draft multiple is 1.3, the distance between a cotton feeding plate and a licker-in is 0.23mm, the distance between the licker-in and a cylinder is 0.25mm, the distance between a cylinder and a cover plate is 0.3mm, 0.25mm, 0.2mm, the distance between the cylinder and a doffer is 0.15mm, the sliver outlet speed is 88.27m/min, the cover plate speed is 260.08mm/min, the licker-in rotating speed is 996r/min, the cylinder rotating speed is 474r/min, and the doffer rotating speed is 26 r/min.

6. A process for producing a pure cotton yarn using a roving-spinning unit according to claim 1 or 2, wherein: the pre-drawing process adopts an JWF1310 type drawing frame, and the specific process parameters are as follows: the dry basis weight is 26.6g/5m, the number of combined yarns is 6, the mechanical total draft is 6.069 times, the actual total draft is 5.948 times, the front draft is 4.895 times, the back draft is 1.805 times, the front draft tension is 1.012N, the back draft tension is 1.042N, the sliver outlet speed is 840m/min, the roller center distances are 45mm and 48mm respectively, the roller diameters are 35mm, the rubber roller pressurization is 120N, 300N, 320N, 300N and the bell mouth diameter is 2.8mm respectively.

7. A process for producing a pure cotton yarn using a roving-spinning unit according to claim 1 or 2, wherein: the strip lap procedure adopts JWF1383 strip lap combination machines, and the specific technological parameters are as follows: the quantitative yarn winding amount is 68.81g/m, the doubling number is 20, the mechanical total draft is 1.508 times, the actual total draft is 1.4778 times, the primary zone draft is 1.314 times, the pre-draft is 1.074 times, the rotating speed of a roller winding is 177.6r/min, the linear speed of the roller winding is 390.54m/min, the roller gauge is 48mm, the roller winding speed is 75m/min, and the feeding tension draft is 1.396 times.

8. A process for producing a pure cotton yarn using a roving-spinning unit according to claim 1 or 2, wherein: the combing process adopts a Lida E86 automatic lap changing comber, and the specific technological parameters are as follows: the doubling number is 8, the sliver ration is 21.02g/5m, the cylinder rotating speed is 380r/min, the cotton feeding rotating speed is 250 mm/clamp, the cotton falling rate is 18%, the roller gauge is 6mm, the cotton falling gauge is 10mm, the lap roller gauge is 0.9614mm, the cotton feeding roller gauge is 6.3420mm, the detaching roller gauge is 0.9976mm, the table top press roller gauge is 1.0148mm, the loop bar press roller gauge is 1.057mm, and the loop bar cylinder gauge is 1.011 mm.

9. A process for producing a pure cotton yarn using a roving-spinning unit according to claim 1 or 2, wherein: the drawing process adopts an JWF1312B type auto-leveling drawing frame, and the specific process parameters are as follows: the dry basis weight is 19.12g/5m, the number of combined yarns is 8, the mechanical total draft is 9.06 times, the actual total draft is 8.87 times, the front draft multiple is 8.118 times, the rear draft multiple is 1.5 times, the front draft tension is 1.038N, the rear draft tension is 1.022N, the sliver outlet speed is 840m/min, the roller center distance is 46mm and 52mm respectively, the rubber roller pressurization is 140N, 400N, the bell mouth diameter is 3.4mm respectively, the pressure bar adjusting ring diameter is 13mm, and the sliver outlet speed is 300 m/min.

10. A process for producing a pure cotton yarn using a roving-spinning unit according to claim 1 or 2, wherein: the specific process parameters of the THC2015 type full-automatic doffing roving frame are as follows: the dry weight of the roving is 3.47g/10m, the mechanical total draft is 11.04 times, the actual total draft is 10.93 times, the calculated twist is 4.37 twist/10 cm, the roller center distance is respectively 38mm, 48mm and 55mm, the front roller rotating speed is 292.67r/min, the spindle rotating speed is 840r/min, the aperture of the front area condenser is 10mm, the jaw space is 5.5mm, and the twist factor is 85.16.

11. A process for producing a pure cotton yarn using a roving-spinning unit according to claim 1 or 2, wherein: the TH598J type four-roller negative pressure type compact spinning automatic doffing spinning frame has the following specific technological parameters: the dry weight of the spun yarn is 5.37g/10m, the mechanical draft is 66 times, the actual draft is 64.68 times, the back zone draft is 1.14 times of the twist direction Z, the twist is 169.98 twists/10 cm, the twist coefficient is 400, the roller gauge is 41.5mm and 75mm respectively, the caliber of the condenser is 1.8mm, the type of the steel wire ring is 13/0, the type of the steel collar is MXKSA 2, the diameter of the steel collar is 36mm, the rotating speed of a front roller is 1485r/min, the rotating speed of a spindle is 20000r/min, and the jaw of a rubber ring is 2.5 mm.