news

Mechanical characteristics of textile machinery

Update:17-04-2020
Summary:

Technology, continuity, complete set; high speed, high […]

Technology, continuity, complete set; high speed, high efficiency, maintenance-saving; standardization, serialization, generalization; low energy consumption, low noise, low pollution, are the characteristics and direction of modern textile machinery. Fengfan NC has been in manufacturing and sale of knitting machinery over 13 years.

 

Manufacturability

In modern times, people continue to deepen their understanding of the structure and physical and chemical properties of fibers, thus creating more and more advanced process methods, which can give full play to the characteristics of fibers and fabrics. In order to cope with this development, modern textile machinery uses mechanical technology, electrical technology, especially weak current technology to create a wide range of processing machines with different performances. For example, there are three preparation processes for industrial coated fabrics: coating method, rolling method and lamination method, and the designed machine has three different structures accordingly. Another example is the low affinity of synthetic fibers for dyes. To this end, high-temperature (130 ° C), high-pressure (2.7 kg / cm) dyeing equipment that can shorten the dyeing time and achieve good dyeing fastness has been created.

 

Continuity

The continuity of textile machinery is subject to the technological process. For example: spinning 20.8 ~ 27.8 cotton yarn, the total draft multiple from cotton to spun yarn is 13900 ~ 19000 times. The process needs to go through the processes of cotton cleaning, carding, drawing, roving, and spinning. Therefore, the draft must be distributed to the corresponding equipment in each process to complete. Another example is the resin processing process (see anti-crease finishing), the fabric is first impregnated with resin in the padding machine, then subjected to high temperature treatment in the baking machine to condense the resin between the fibers, and finally removed by soaping and water washing in the flat washer The combined resin residues are dried in a dryer. The entire process is determined by process requirements, and the steps cannot be reversed, unconditionally omitted or combined.

 

Completeness

The completeness of textile machinery is also subordinated to craftsmanship. For example, the complete set of machines is configured according to the cotton spinning process. The fixed relationship between the type of machine arrangement and the number of machines is determined by the process requirements. Another example is the product woven by a loom with a certain working range, which needs to be equipped with cloth inspection, measuring cloth and dyeing and finishing equipment of the corresponding working range, which is also a complete set. Therefore, the completeness of textile machinery exists not only in a factory, but also between factories.

 

High speed

One of the main development characteristics of modern textile machinery is to continuously increase the speed of the machine to obtain high output, to reduce the number of equipment equipped, reduce the plant area, save investment and labor, and achieve greater results with less capital. The numbers in Table 1, Table 2 and Table 3 illustrate the trend of high-speed textile machinery.

The main measures to improve the running speed of textile machinery are to design the structure of parts more reasonably, use excellent performance materials and improve the processing accuracy.

 

High efficiency

The high efficiency of textile machinery is achieved on the basis of high speed and corresponding other measures. For example, the successful development of the exhaust cotton box and the automatic leveling device of the carding machine has realized the combination of cotton cleaning and carding, thereby eliminating the coiling process and the cotton cleaning device, saving a lot of handling work and improving efficiency. Due to the use of self-leveling device for combed wool (see drafting self-leveling), the number of front spinning process is reduced from 7-10 in the 40s to 4-7, which reduces the number of machine sets, saves plant area and saves Investment and labor, and reduce costs. The gradual replacement of heavy manual labor with mechanized and automated devices and the reduction of operating workers are yet another measure to improve the working efficiency of textile machinery. The modern spinning frame is equipped with an automatic doffing cannulation device, which replaces the heavy manual doffing operation; the automatic splicing device replaces the manual touring splice. Textile machinery was originally perfected to simulate human movements, and it has become a highly automated machine with artistry and ingenuity. The microelectronics technology, microprocessors and electronic computers produced by the development of large-scale integrated circuits have begun to penetrate into single and complete sets of textile machinery. The high-speed automatic winder is equipped with an electronic yarn clearer, which can automatically detect yarn defects and coarse details, automatically cut off and automatically knot, and can also interface with the microprocessor for the classification and statistics of yarn defects and coarse details. The cloth inspection machine equipped with a microprocessor can display the statistics of the defect type, the position of the defect, the length of each roll of cloth (excluding the bad cloth part) and the weight in the form of a statistical table, and can be checked in a batch of cloth After finishing, output the report of the total volume of the batch of cloth, the number of classified defects and the deduction of the bad cloth. You can also print out the result or record it on the magnetic tape for future inspection.

 

Province maintenance

Modern textile machinery is fully designed to reduce maintenance and extend service life. After careful consideration in the selection of materials and the formulation of heat treatment processes, the parts have a long service life and reliable operation. Some parts are filled with lubricant once at the time of assembly, and there is no need to add oil for several years; some use detection devices to prevent accidents; some use special processing to make the parts have a mirror finish, and so on.

 

Standardization

The repetition coefficient of the same part of each machine is another feature of textile machinery. Taking a spinning machine as an example, each machine has 400 spindles, and spinning 400 yarns at the same time requires 400 each of the same ring and spindle. As for the number of needles for knitting machines is even greater. Each high-speed warp knitting machine with a working width of 6.6 meters requires 7280 groove knitting needles. The machinery factory producing these parts needs to design the corresponding tools, fixtures, molds according to the batch size of the parts to a dedicated multi-station automatic machine tool or a dedicated assembly line to ensure the high efficiency, high quality and low cost of the production of these parts. The complexity of textile machinery parts is also manifested in types, because different processing objects require different types of parts to be designed and manufactured according to different raw materials such as cotton, hemp, wool, silk, chemical fiber and so on. For example, woolen spinning spindles have larger dimensions than cotton spinning spindles, but the structure is similar. As another example, due to the variety of fabric widths, there must be models with identical structural principles and different working ranges. If the above parts and machine parameters are allowed to develop arbitrarily, it will have an adverse impact on the product design efficiency, production management and production costs of the textile machinery factory, and will increase the management of the textile mill's equipment, spare parts storage, maintenance and replacement. The workload even caused disturbances in factory management. The purpose of standardization is to use the main technical parameters that are as simple as possible and the distribution of numerical values ​​is appropriate as the design basis for a group of machines with different capacities under the principle of meeting different process requirements. For example, according to the spindle pitch, the loom and the printing and dyeing machine according to the working range, and the knitting machine according to the diameter of the cylinder, each forms a serial design. Fengfan adopt the latest A8 high-speed processor, to bring you unparalleled operational experience in flat knitting machine.

 

Serialization

In a series of machines designed in series, there are some parts or components that have nothing to do with the parameters of the machine series. They can be applied to the machines of this series within a certain range, such as the head part of the spinning machine and the parts of the lifting part. In addition, some parts play the same function on different models, such as the guide rollers and rollers of the printing and dyeing machine. These parts are called general-purpose parts or general-purpose devices, and are further developed into general-purpose unit machines in printing and dyeing machines.

 

Universal

In the design of mechanical products, in addition to using universal parts, universal devices, and universal unit machines as much as possible, people also consciously modify the structural layout appropriately and implement the principle of generalization as much as possible. The standardization, serialization, and generalization of textile machinery have begun to cross the border between countries and countries and become international. For example, parts and components of drafting mechanisms, knitting needles, and clothing have adopted the same parameters in many countries.

 

Low energy consumption

The energy saving of textile machinery is focused on dyeing and finishing equipment because of its great potential. For example, in a flat washing machine with a production capacity of 1,000 kg per hour, the waste water with a discharge temperature of 98 ° C can be used to heat the fresh water needed by itself, which can save tens of thousands of yuan per year only by single shift calculation. The jet dyeing machine can reduce the dyeing bath ratio from 1:20 to 1:30 to 1: 5 to 1:15 of the ordinary dyeing machine, and the dyeing time can be shortened by 50%. Although the large-capacity pump is required to increase the power consumption of the jet dye liquor in the machine, the total energy is still saved. Transfer printing has been used in production in the 1970s. It is characterized by low emission, energy saving and less pollution. Solvent sizing can reduce water consumption and energy consumption.

 

Low noise

The main hazards produced by textile machinery during use are noise, dust, toxic and harmful gases and waste water containing harmful substances. There are two reasons for equipment and process factors. Noise is a kind of mechanical vibration wave with air as a carrier. In most workshops of textile mills, especially in weaving workshops, the mechanical noise is very high. The measures that can be taken in textile machinery are: the inner wall of the shell is lined with sound-absorbing materials, the chain drive and gear drive are replaced with flexible toothed transmission belts, the accuracy and dynamic balance of moving parts are improved, between the high-speed parts and the frame Install shock-absorbing washers, etc. However, some noise reduction measures also bring negative factors, such as inconvenient operation and maintenance after installing a soundproof cover. Creatively improving the mechanical design is a fundamental measure to reduce noise. For example, the noise of shuttleless looms (see weaving) has gradually approached the requirements of environmental protection. In order to reduce the spread of fine dust during the operation of the equipment, the design of the spinning machine can be improved. For example, the sealing of the outer cover can be improved. The air-conditioning device can also be used to absorb the dust-laden air in the workshop for centralized filtration and then return the fresh air to the workshop; The equipment is used for machines such as cotton cleaning, carding, combing, etc., to filter the discharged dusty air and recover the noil, so that the air reaches the environmental protection regulations.

 

Low pollution

In addition, changes in the composition of textile machinery materials are also characteristics of the development of modern textile machinery. Cast iron turned out to be the main structural material of textile machinery because it is rich in resources, cheap, easy to process, and can be cast into complex shapes. It is relatively corrosion-resistant and has good shock absorption, but it is gradually used by steel and welded parts. , Alloy die castings, the percentage of weight in each machine is significantly reduced. Wood was originally the main structural material of textile machinery. Due to excessive deforestation, resources are becoming scarce and gradually replaced by engineering plastics and light metals. Composite engineering plastics have excellent properties that wood does not have, such as high strength, corrosion resistance, water resistance, Weather resistance, wear resistance, etc. High-quality steel is also more used as materials such as transmission shafts, gear blanks, connecting rods, cams and so on. In order to resist the acidic corrosion of dyes and the high temperature corrosion of organic substances, nickel and chromium stainless steel containing molybdenum and titanium is mostly used as containers, machine room walls, cloth guide rollers and other parts in contact with fabrics and media. Chemical fiber machinery more widely uses heat-resistant and acid-resistant advanced alloy steel for spinnerets, screw extruders, metering pumps, and other parts in contact with polymers and parts that work in liquids containing organic solvents at high temperatures.

0
Views: 229