CN110607629A - Device and method for carrying out primary wet pretreatment on cotton knitted fabric - Google Patents

Abstract

The invention discloses a device for carrying out primary wet pretreatment on cotton knitted fabrics, which comprises a rotary drum wet treatment unit and a blade rotary wheel wet treatment unit which are sequentially arranged, wherein: a drum wet treatment unit for applying an ordered tension to the fabric; a blade wheel wet treatment unit for fully relaxing the fabric; steam heating pipes are arranged at the bottoms of the rotary drum wet treatment unit and the blade rotating wheel wet treatment unit; the invention also discloses a method for carrying out primary wet pretreatment on the cotton knitted fabric. The invention has relatively simple structure and easy manufacture, the drum wet treatment unit can apply ordered tension to the fabric, and the blade rotating wheel wet treatment unit can fully relax the fabric, thereby achieving the effects of controlling the density range of the cotton knitted fabric, improving the stability of the cotton knitted fabric with size and preventing the wrinkle.

Description

Device and method for carrying out primary wet pretreatment on cotton knitted fabric

Technical Field

The invention relates to the technical field of cotton knitted processing processes, in particular to a device and a method for carrying out primary wet pretreatment on cotton knitted fabrics.

Background

The density (usually measured by weight per unit area), dimensional stability (usually measured by shrinkage) and fabric flatness of knitted fabrics of cellulose fibers such as cotton, hemp, viscose, etc. are closely related to the processing mode and equipment adopted in the scouring, bleaching and dyeing processes.

The current industry generally adopts rope dyeing machines produced in an intermittent mode to carry out the working procedures of scouring, bleaching, dyeing, water washing and the like, the scouring and bleaching in a continuous production mode is applied to a few enterprises and becomes the development direction of scouring and bleaching technology in the future, and continuous dyeing and semi-continuous dyeing (which refers to a continuous water washing post-treatment process after the intermittent dyeing) also become important knitted fabric dyeing methods. However, whether batch-wise or continuous, the current equipment and process have many disadvantages that are difficult or even impossible to overcome.

For example, the rope dyeing machine is used for scouring, bleaching, dyeing and washing, and has the advantages of high fabric relaxation degree, large fabric density (weight per unit area) after processing, good dimensional stability (low shrinkage rate), and wide fabric range, such as adaptability to various states of tubular, open width and hemming knitted fabrics, so the rope dyeing machine becomes a method commonly adopted in the past and the present industry, but the method has the defects of poor product quality stability, large water and electricity consumption, more labor and the like, can cause fabric wrinkles, fabric scratches and the like, and once the defects are caused, the defects can not be overcome; the knitted fabric is continuously scoured, bleached, dyed, washed and the like in an open width state, the problems of cloth cover wrinkles, cloth cover scratches and the like can be solved, the quality stability of products can be improved, the consumption of steam, labor and the like can be greatly reduced, and the knitted fabric is stretched by large tension in the running process, so that the density of the knitted fabric is low (the weight of a unit area is low) and the dimensional stability is poor (the shrinkage rate is high).

Therefore, the problems of low density, poor dimensional stability and wrinkle on the cloth cover of the cotton knitted fabric in the processing process of the cotton knitted fabric are urgently needed to be solved.

Disclosure of Invention

In order to solve the technical problems of low density, poor dimensional stability and cloth cover wrinkles of the cotton knitted fabric, the invention discloses a device and a method for carrying out primary wet pretreatment on the cotton knitted fabric.

In order to achieve the purpose, the invention adopts the following technical scheme:

the utility model provides a device for carry out wet preliminary treatment of first to cotton knitted fabric, includes the wet processing unit of rotary drum and the wet processing unit of blade runner that set gradually in proper order, wherein:

the drum wet processing unit is used for applying ordered tension to the fabric;

the blade runner wet treatment unit is used for fully loosening the fabric;

and steam heating pipes are respectively arranged at the bottoms of the rotary drum wet treatment unit and the blade rotating wheel wet treatment unit.

As a further preferable mode for the present invention, the drum wet processing unit includes a cloth feeding roller, rotating drums and showers, a tension bracket and a first cloth guide roller are sequentially disposed below the cloth feeding roller, one central rotating drum of the three rotating drums is disposed at the middle position of the drum wet processing unit, the other two rotating drums are symmetrically disposed at the left lower part and the right lower part of the central rotating drum, and a plurality of showers are further disposed along the periphery of the central rotating drum.

As a further preference for the present invention, the drum is made of a porous stainless steel plate having a diameter of not less than 800 mm.

As a further preferable aspect of the present invention, a padder is installed at an upper right position of the drum wet processing unit, a second cloth guide roller is installed in front of the padder, and a spreading plate is further installed between the padder and the second cloth guide roller.

As a further preferable feature of the present invention, the vane wheel wet processing unit includes a vane wheel, a multi-edge roller is disposed on the upper left of the vane wheel, a third cloth guide roller is directly mounted on the multi-edge roller and the padder, a width expanding-centering roller is disposed on the upper right of the vane wheel, and a cloth discharge press roller is further disposed outside the vane wheel wet processing unit.

As a further preferable aspect of the present invention, a cloth amount controller is further installed between the blade runner and the tenter-centering roller.

As a further preference for the present invention, the outer diameter of the vane wheel is 1500-.

Another object of the present invention is to provide a method for primary wet pretreatment of a cotton knitted fabric, which uses the above apparatus for primary wet pretreatment of a cotton knitted fabric, comprising the steps of:

a. the knitted fabric sequentially passes through cloth feeding and air sealing in an open width state and enters a drum wet treatment unit under the traction of a cloth feeding roller to carry out a drum wet treatment process;

b. after the wet treatment by the rotary drum, the wet treated water enters a wet treatment unit of the blade rotating wheel by the traction of a padder to carry out the wet treatment process of the blade rotating wheel;

c. finally, the cloth is discharged from a cloth discharging roller through a liquid seal port, and the whole primary wet pretreatment process is completed.

As a further preferable aspect of the present invention, the temperature in the steam heating pipe is controlled to be between room temperature and 100 ℃ in the drum wet treatment process and the drum wet treatment process.

In the drum wet treatment unit, the friction force between the surface of the porous stainless steel drum and the fabric can ensure that the fabric transverse external force is uniform and ordered in the process, and the fabric is subjected to a moderate (adjustable) and ordered wet treatment process by the longitudinal external force and the transverse external force in the drum wet treatment unit, so that the loosening and shrinking uniformity and density of the fabric in the next step of blade wheel wet treatment are ensured.

It should be noted that:

1. the reason why the wrinkles are generated in the knitted cotton fabric

The cotton knitted fabric, especially the single-sided knitted fabric, is very easy to generate the phenomenon that the phenomenon seems to be 'fold crease' which can not be eliminated by after-treatment in the dyeing and finishing process, and the cloth cover appearance effect of the fabric is seriously influenced. The root cause of this phenomenon is also closely related to the phenomenon of water-swelling of the fibers in water, which is mainly manifested by thickening of the cross-sectional area of the fibers.

The water absorption and swelling of the cellulose fiber knitted fabric such as cotton, hemp, viscose and the like placed in water (solution) inevitably cause the change of a yarn structure and a loop structure, the change of the yarn structure is represented by thickening, shortening and increasing of twist of the yarn, the change of the loop structure is represented by increasing of loop arc and shortening of loop column or reducing of loop column spacing, and the two changes result in compact shrinkage of the fabric. The process of yarn shrinkage and the change of knitted loop structure due to the swelling of the fibers by water absorption are shown in fig. 2 and 3.

Due to the constraint of the yarn interweaving resistance and the cohesion force among fibers on the fabric weave structure, although the fiber swelling process is reversible, the shrunk and compact fabric form cannot be restored due to the restoration of the fiber form.

When the dense and loose single-sided cotton knitted raw gray fabric is subjected to primary wet processing (such as scouring and bleaching), if the fabric is subjected to irregular external force (different in size and random in direction), such as fabric rope running, compression roller extrusion, dyeing machine nozzle extrusion, fabric stacking extrusion and the like, when the fiber is not swelled or the swelling effect is poor, the yarn structure (expressed as twist) and the fabric structure (expressed as three-dimensional space of the sleeve joint) can be unevenly changed due to poor fiber cohesive force and low yarn interweaving resistance, so that the shrinking and compacting effect of the fabric due to fiber swelling is uneven, the fabric has uneven density and different three-dimensional space of the sleeve joint point, but can not be recovered due to the greatly increased fiber cohesive force and yarn interweaving resistance after swelling and shrinking, so that the phenomenon of 'fold crease' is formed. The double-sided knitted fabric has quite high yarn interweaving resistance and fiber cohesion in a grey fabric state due to the fabric tissue structure, and the fabric cannot shrink unevenly due to the action of irregular external force during primary wet processing (such as scouring and bleaching).

Because the primary wet processing procedure of the cotton knitted fabric is mostly scouring and bleaching, and rope scouring and bleaching is generally carried out by using a dyeing machine, technicians can easily mistakenly think that the crease which cannot be eliminated by after finishing of the single-sided cotton knitted fabric is caused by the rope scouring and bleaching, and the crease can be overcome only by adopting open width scouring and bleaching.

The most effective step for preventing the single-sided cotton knitted fabric from generating crease (which may be called as "dead fold") phenomenon that cannot be eliminated by after-finishing is the "primary wet treatment process" performed on the cotton knitted fabric, that is, the first wet treatment process performed on the fabric knitted from the loom, and there are two ways:

the first way is as follows:

before the fabric is subjected to irregular tension and pressure, the fabric is immersed in water in a completely relaxed state, and the fabric is freely and uniformly shrunk through fiber swelling; the fabric which is uniformly shrunk and dense can be relatively and stably fixed under the action of cohesive force between fibers and interweaving resistance between yarns, and can not generate 'dead folds' under the action of pressure or pulling force (with proper magnitude) in subsequent processing.

And (2) a second way:

before the fabric is subjected to irregular tension and pressure, the fabric is subjected to wet processing under the action of regular external force with proper magnitude (including transverse direction and longitudinal direction), under the condition that the fabric form change caused by the water absorption and swelling of the fibers is uniform and orderly, namely a flat cloth cover is formed, meanwhile, the fiber cohesion and yarn interweaving resistance of the new-form fabric are improved, and dead folds cannot be generated under the action of the pressure or the tension (with proper magnitude) in subsequent processing.

2. Reasons for lower density and poorer dimensional stability of cotton knitted fabrics in open-width continuous scouring and bleaching

The phenomena of low density and poor dimensional stability of cotton knitted fabrics after open width continuous scouring and bleaching are caused by excessive stretching of the fabrics by the used equipment, and the stretching effect is mainly from a primary wet treatment process. The existing equipment for continuously scouring and bleaching cotton knitted fabrics neglects the point, only focuses on controlling the tensile tension and the directionality, but does not give a relaxation opportunity (needing in water) to the fabrics, the 'primary wet treatment' under the action of the ordered external force can ensure that the fabrics are not easy to form wrinkles due to the external force (stretching and pressurizing) in subsequent processing to obtain a flat cloth cover effect through the formed new and higher fiber cohesive force and interweaving resistance, but can also prevent the relaxation and retraction of fibers, yarns and coil structures in the subsequent processing (such as dyeing and washing) due to the new and higher fiber cohesive force and interweaving resistance, so that the density (the weight in unit area) of the fabrics is lower and the water shrinkage rate of end products is higher.

The most fundamental approach is to give the fabric full underwater relaxation treatment in the primary wet treatment process, eliminate the fiber internal stress and yarn internal stress caused in the spinning and weaving processes, and make the fabric shrink uniformly and compactly through the water absorption and swelling of the fiber.

In the invention, the density, the dimensional stability and the cloth cover wrinkle prevention effect of the cotton knitted fabric are mainly completed by the blade rotating wheel wet treatment unit.

Through the interval of the runner blades on the fabric and the buoyancy effect of water on the fabric, the fabric can be fully and loosely placed in the water solution of the blade runner wet treatment unit, and the fabric can freely and uniformly shrink through the water absorption and swelling of the fiber; the fabric structure which is uniformly shrunk and dense can be relatively stably fixed due to the action of newly formed larger cohesion force between fibers and interweaving resistance force between yarns, deformation caused by the action of pressure or pulling force (with proper magnitude) is not easy to generate in subsequent processing, so-called 'dead folds' caused by the action of irregular (with different magnitude and different direction) pressure or pulling force (with proper magnitude) are not easy to generate, and even if certain deformation (elongation or widening) is generated due to tensile tension, the fabric structure can be easily recovered through after finishing (such as overfeeding tentering, vibration drying, mechanical preshrinking and the like).

The fabric has short time in a 'drum wet processing unit', is not enough to form larger fiber swelling, has transverse friction effect of a drum on the fabric and stretching effect on the longitudinal direction of the fabric caused by the fact that the fabric keeps running in an open width mode, so that the fabric does not shrink in the process, but the process is beneficial to ensuring the flatness of the fabric and effectively controlling the density (weight per unit area) of the fabric, and the density (weight per unit area) of the fabric can be controlled within a required range by increasing or reducing the tension force applied to the running of the fabric through adjusting a tension frame.

The density of the fabric is related to the degree of wetting and penetration of the fabric in the wet drum treatment unit, in addition to the amount of tension to which the fabric is subjected in the wet drum treatment unit. Under the action of the tension with the same magnitude, the wetting degree and the penetration degree are better, the free shrinkage degree of the fabric in a subsequent blade rotating wheel wet processing unit caused by fiber swelling is smaller, and the fabric density is smaller; in addition, the wetting and penetration degree of the fabric in the drum wet processing unit is related to the temperature of the processing liquid and the selected auxiliary agent (surfactant), and the lower the temperature of the processing liquid and the smaller the wetting effect of the surfactant, the poorer the wetting and penetration degree of the fabric is, and the higher the fabric density is correspondingly realized in the blade wheel wet processing unit; the maximum fabric density is the condition where the fabric passes through the drum wet treatment unit in a "dry cloth" state, i.e., where no water is present.

The beneficial effect of the invention is that,

1. the drum wet processing unit has the advantages that longitudinal external force and transverse external force experienced by the fabric are proper and orderly wet processing processes, and the loosening and shrinking uniformity and density of the fabric in the next step of blade rotating wheel wet processing are favorably ensured;

2. in the blade runner wet treatment unit, the fabric can be fully and loosely placed in the aqueous solution of the blade runner wet treatment unit through the interval of the runner blades on the fabric and the buoyancy action of water on the fabric, the fabric can freely and uniformly shrink through water absorption and swelling of the fiber, deformation caused by the action of pressure or tension is not easy to generate, and so-called wrinkles caused by the action of irregular pressure or tension are not generated.

The device has relatively simple structure and easy manufacture, the drum wet treatment unit can apply ordered tension to the fabric, and the blade rotating wheel wet treatment unit can fully relax the fabric, thereby achieving the effects of controlling the density range of the cotton knitted fabric, improving the stability of the cotton knitted fabric with the size and preventing the wrinkle.

Drawings

FIG. 1 is a schematic structural view of the present invention;

FIG. 2 is a schematic diagram of yarn shrinkage due to fiber swelling;

FIG. 3 is a schematic representation of shrinkage of a knitted fabric caused by fiber swelling.

Wherein, 1-cloth is put in; 2, a cloth discharging roller; 3-feeding a cloth roller; 4-a tension bracket; 5-rotating the drum; 6-a sprayer; 7-a first cloth guide roller; 8-unfolding the edge plate; 9-padder; 10-a multi-edge roller; 11-a vane wheel; 12-tentering-centering roll; 13-a cloth quantity controller; 14-steam heating pipe; 15-air sealing; 16-liquid sealing; 17-a second cloth guide roller; 18-third fabric guide roll.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

As shown in fig. 1, an apparatus for primary wet pretreatment of a cotton knitted fabric comprises a drum wet treatment unit and a vane wheel wet treatment unit sequentially arranged in this order, wherein:

a drum wet treatment unit for applying an ordered tension to the fabric;

a blade wheel wet treatment unit for fully relaxing the fabric;

steam heating pipes 14 are arranged at the bottoms of the rotary drum wet treatment unit and the blade rotating wheel wet treatment unit.

Particularly, the rotary drum wet processing unit comprises a cloth feeding roller 3, rotary drums 5 and sprayers 6, a tension bracket 4 and a first cloth guide roller 7 are sequentially arranged below the cloth feeding roller 3, one central rotary drum 5 of the three rotary drums 5 is arranged in the middle of the rotary drum wet processing unit, the other two rotary drums 5 are symmetrically arranged on the left lower side and the right lower side of the central rotary drum 5, the sprayers 6 are further arranged on the periphery of the central rotary drum 5, and water absorption permeation of the fabric can be accelerated by spraying.

The tension bracket 4 can adjust and control the rotation speed of the padder 9 in time through tension sensing so as to ensure the magnitude of the longitudinal tension of the fabric, the smaller the tension is, the smaller the longitudinal stretching degree of the fabric is, and the greater the fabric density (weight per unit area) is, of course, the tension can be properly increased so as to control the fabric density within the required range.

In particular, the drum 5 is made of a porous stainless steel plate having a diameter of not less than 800 mm. The friction force between the surface of the porous stainless steel drum 5 and the fabric can ensure that the fabric transverse external force is uniform and orderly in the process, and the longitudinal external force and the transverse external force of the fabric, which are experienced by the drum wet treatment unit, are moderate (adjustable) and orderly wet treatment processes, so that the loosening and shrinking uniformity and density of the next blade rotating wheel wet treatment fabric can be ensured.

In particular, the padder 9 is installed at the upper right position of the drum wet processing unit, the second cloth guide roller 17 is arranged in front of the padder 9, the edge unfolding plate 8 is further installed between the padder 9 and the second cloth guide roller 17, and the edge unfolding plate 8 can ensure that the fabric can not be curled and pass through the padder 9.

Particularly, the wet processing unit of the blade rotating wheel comprises a blade rotating wheel 11, a multi-edge roller 10 is arranged at the upper left part of the blade rotating wheel 11, a third cloth guide roller 18 is directly arranged on the multi-edge roller 10 and a padder 9, an expanding-centering roller 12 is arranged at the upper right part of the blade rotating wheel 11, and the expanding-centering roller 12 has three functions of expanding, centering and edge expanding, and can prevent fabrics fully loosened under liquid from deviating during cloth discharging; and a cloth outlet press roller is also arranged outside the blade rotating wheel wet processing unit. The fabric is guided into the space between the blades through the polygonal roller 10, the blade rotating wheel 11 rotates for a certain angle (the angle between two adjacent blades) at certain intervals, the interval time can be set according to the density of the fabric, and the interval time is shorter when the density is higher so as to ensure the looseness of the fabric between the blades; the starting and stopping of each rotation of the blade runner 11 also stir the movement of water while driving the fabric to move forwards, and the impact between the water and the fabric can accelerate the shrinkage of the fabric in the water caused by the water absorption and swelling of the fibers.

In particular, a cloth amount controller 13 is also arranged between the blade rotating wheel 11 and the expanding-centering roller 12, and the cloth amount controller 13 can adjust the cloth discharging speed of the fabric at the cloth discharging roller 2 through a feeler lever, a sensor and a mechanical device to ensure that the fabric has enough free relaxation and contraction time to realize the optimal fabric density.

In particular, the outer diameter of the blade rotating wheel 11 is 1500-2000mm, the number of the blades is 10-18, and the plurality of blades divide the fabric introduced into the unit water into a plurality of parts so as to ensure the looseness and the sufficient cloth containing amount of the fabric in the water.

A method of primary wet pretreatment of a cotton knit fabric comprising the steps of:

a. the knitted fabric passes through a cloth feeding roller 1 and an air seal 15 in sequence in an open width state and enters a drum wet treatment unit under the traction of a cloth feeding roller 3 to carry out a drum wet treatment process;

b. after the wet treatment by the rotary drum, the wet treated water enters a wet treatment unit of the blade rotating wheel by the traction of a padder 9 to carry out the wet treatment process of the blade rotating wheel;

c. finally, cloth is discharged from the cloth discharging roller 2 through the liquid seal 16, and the whole primary wet pretreatment process is completed.

In particular, in the drum wet treatment process and the vane wheel wet treatment unit process, the impregnation liquid is generally an aqueous solution containing a proper penetrating agent, the heating mode is an indirect steam pipe, and the temperature in the steam heating pipe 14 is controlled between room temperature and 100 ℃.

It is to be understood that the above description is not intended to limit the present invention, and the present invention is not limited to the above examples, and those skilled in the art may make modifications, alterations, additions or substitutions within the spirit and scope of the present invention.

Claims (9)

1. The utility model provides a carry out wet pretreatment's device for a time to cotton knitted fabric which characterized in that, includes the wet processing unit of rotary drum and the wet processing unit of blade runner that the order set up in proper order, wherein:

the drum wet processing unit is used for applying ordered tension to the fabric;

the blade runner wet treatment unit is used for fully loosening the fabric;

and steam heating pipes are respectively arranged at the bottoms of the rotary drum wet treatment unit and the blade rotating wheel wet treatment unit.

2. The apparatus of claim 1, wherein the drum wet processing unit comprises a cloth feeding roller, a drum and a sprayer, a tension bracket and a first cloth guide roller are sequentially disposed below the cloth feeding roller, a central drum of the three drums is disposed at a middle position of the drum wet processing unit, the other two drums are symmetrically disposed at a lower left and a lower right of the central drum, and a plurality of sprayers are further disposed along an outer circumference of the central drum.

3. An apparatus for primary wet pretreatment of a cotton knitted fabric according to claim 2, wherein said drum is made of a perforated stainless steel plate having a diameter of not less than 800 mm.

4. The apparatus for primarily wet-pretreating a cotton knitted fabric according to claim 2, wherein a padder is installed at an upper right position of the drum wet-processing unit, a second fabric guide roller is disposed in front of the padder, and a spreading plate is further installed between the padder and the second fabric guide roller.

5. The apparatus for primary wet pretreatment of cotton knitted fabric according to claim 1, wherein said vane wheel wet treatment unit comprises a vane wheel, a polygon roll is disposed at the upper left of the vane wheel, a third cloth guide roll is directly installed at the polygon roll and the padder, a width expanding-centering roll is disposed at the upper right of the vane wheel, and a cloth discharging pressure roll is disposed at the outside of said vane wheel wet treatment unit.

6. An apparatus for primary wet pre-treatment of a cotton knitted fabric as claimed in claim 5, wherein a cloth amount controller is further installed between said vane wheel and said expander-centering roller.

7. The apparatus for primary wet pretreatment of cotton knitted fabric according to claim 6, wherein the outer diameter of the blade wheel is 1500-2000mm and the number of blades is 10-18.

8. A method for primary wet pretreatment of a cotton knitted fabric using the apparatus for primary wet pretreatment of a cotton knitted fabric according to any one of claims 1 to 7, comprising the steps of:

a. the knitted fabric sequentially passes through cloth feeding and air sealing in an open width state and enters a drum wet treatment unit under the traction of a cloth feeding roller to perform a drum wet treatment process;

b. after the wet treatment by the rotary drum, the wet treated water enters a wet treatment unit of the blade rotating wheel by the traction of a padder to carry out the wet treatment process of the blade rotating wheel;

c. finally, the cloth is discharged from a cloth discharging roller through a liquid seal port, and the whole primary wet pretreatment process is completed.

9. The method of primary wet pretreatment of cotton knitted fabrics according to claim 8, wherein the temperature in the steam heating tube is controlled between room temperature and 100 ℃ during the drum wet treatment.