A transformer is a device used for converting electrical energy, which can increase or decrease the voltage of alternating current to meet the needs of different circuits. The working principle of transformers is based on the principle of electromagnetic induction. Below, we will provide a detailed introduction to the production process and working principle of transformers. The production process of transformers The production process of transformers mainly includes the following steps: 1. Preparation materials: The main materials for transformers include iron cores, coils, and insulation materials. Prepare corresponding materials according to the specifications and design requirements of the transformer. 2. Coil winding: According to the design requirements, the wire is wound on the iron core to form primary and secondary coils. 3. Assembly: Assemble the wound coil, iron core, and other components together to form a complete transformer. 4. Testing: Test the assembled transformer to check whether its electrical and mechanical performance meets the design requirements. 5. Packaging: Qualified transformers are packaged for delivery and use after testing. Working principle of transformers The working principle of a transformer is based on the principle of electromagnetic induction, as follows: When alternating current passes through the primary coil, an alternating magnetic field is generated, which passes through the iron core and generates induced electromotive force in the secondary coil. Due to the electromagnetic coupling between the secondary coil and the primary coil, the induced electromotive force in the secondary coil is proportional to the current in the primary coil. Therefore, by changing the current in the primary coil (i.e. changing the applied voltage), the induced electromotive force in the secondary coil can be changed, thereby achieving an increase or decrease in voltage. 4. In addition, according to the law of electromagnetic induction, the induced electromotive force is proportional to the number of turns in the coil. Therefore, by changing the number of turns in the coil, the voltage can also be increased or decreased. In short, a transformer is an electrical energy conversion device based on the principle of electromagnetic induction, which can increase or decrease the AC voltage by changing the number of coil turns or the applied voltage. The production process of transformers includes steps such as preparing materials, winding coils, assembling, testing, and packaging. Understanding the production process and working principle of transformers helps to better understand and apply this important electrical equipment.

Drones, once only used in the military field, are now redefining precision agriculture. Nowadays, the number of farmers using drones on their own farms is steadily increasing. Various drones provide them with low-cost aerial camera platforms. In this way, farmers can monitor crops in an economically effective way. In use, drones are used to capture crop images, which are later processed by specialized software to obtain reflectance images of farm crops. Currently, there are more and more extreme weather conditions. Accompanying the growth of the world population is a huge increase in the consumption of agricultural products. Considering these circumstances, more and more farmers are expected to use drone technology. The use of drones in the agricultural sector has brought many benefits. But like any other technology, drones also have their advantages and disadvantages, which intentional buyers should be aware of before making a purchase. Advantages of agricultural drones 1. Agricultural analysis Drones can be used for soil and farmland analysis. With the help of drones, accurate 3D maps can be generated for analysis of soil properties, soil moisture content, and soil erosion, which are crucial for precision seeding in planting modes. Even after planting, the above information on farmland irrigation and nitrogen level management is very helpful. 2. Planting At present, although drone planting is not yet common, some manufacturers have proposed system solutions that hope to shoot pods containing seeds and plant nutrients into prepared farmland soil, which will greatly reduce planting costs. 3 Monitoring One of the biggest obstacles in agricultural production is the inability to efficiently monitor crops in large areas of farmland. The emergence of unpredictable weather patterns leads to increased risks and maintenance costs, making this obstacle even worse. Drones can be used to create time series animations that display accurate crop growth conditions, allowing for better management of crops by showcasing their precise growth processes. 4. Agricultural spraying By using ultrasonic echoes and lasers, drones can adjust their flight altitude according to changes in terrain and geography. The ability of drones to scan and adjust their distance from the ground enables them to spray the correct amount of medication in real-time and evenly. This improves efficiency and minimizes the amount of groundwater infiltration. The use of drones for spraying has been proven to be faster than other traditional methods. 5. Irrigation Drones equipped with thermal and hyperspectral sensors can identify parts of the field that have become dry, which can help people irrigate accurately and timely at specific locations. 6. Health assessment Some drones can scan crops through visible light and near-infrared light, and the light processing equipment they carry can recognize the amount of green light and near-infrared light reflected by plants. These data are then used to develop multispectral images that describe the health status of plants. These images can be used to track the health status of crops and provide recommendations for remedial measures upon detecting any diseases. 7. Easy to deploy Unlike traditional aircraft, drones are easier to deploy and have lower costs. Disadvantages of agricultural drones 1. Flight time and range There are also some issues with agricultural drones, with most drones having a short flight time, typically between 20 minutes and 1 hour. This flight time limits the area that each flight battery can cover. And the flight range also limits the radius within which a single drone can fly. Drones with longer flight times and larger flight radii are expensive. 2. Initial purchase cost Drones that can be used in the agricultural field are quite expensive. The current cost of fixed wing drones is as high as $25000. There are also some drones whose high prices include hardware, software, tools, and imaging sensors. Purchasing drones without relevant equipment is cheap, but the high cost of cameras and processing software that meet the requirements makes the difference between the two not significant. However, the cost of purchasing a complete set of agricultural drone equipment in the short term is high, but it is worth it in the long run. 3. Federal laws According to federal law in the United States, drones used for agricultural purposes are considered commercial, which means farmers need to receive FAA operator training and obtain remote driving certificates or hire operators with such qualifications. The FAA also requires drones to fly at an altitude not exceeding 400 feet. Interference within the airspace of 4 Agricultural drones and manned aircraft share the same airspace, making them susceptible to interference with each other. Therefore, it is recommended to submit a flight plan to the local airport or FAA before using the drone. 5. Highly affected by weather conditions Unlike traditional aircraft, drones are more susceptible to the influence of climate conditions. If it is windy or rainy outdoors, the drone will not be able to fly. 6. Knowledge and skills The images obtained by drones require professionals to convert them into useful information, which means that ordinary farmers may need to attend training or have to hire professional analysis software personnel to assist with image processing. Drone technology is constantly improving every day, and as more and more manufacturers enter the industry, the cost of drones and related equipment will decrease. It is expected that limitations such as flight time and range will be addressed through technological improvements. This will enable farmers to gain more benefits from the use of drones.

In today's rapidly developing electric vehicle market, choosing the right charging station has become one of the important issues faced by car owners. What is the difference between DC charging stations and AC charging station areas? What aspects are different? What are the applicable scenarios for each? How to choose different scenarios? This article will provide you with a detailed explanation. Working principle of DC charging station and AC charging station The charging process of electric vehicles requires the conversion of alternating current (AC) from an external power source into direct current (DC) stored in the battery. The AC charging station hands over this conversion process to the car charger, which converts the external AC power into DC power for storage. The DC charging station completes the conversion process from AC to DC inside the charging station, directly supplying DC power to the electric vehicle battery. Advantages and Applications of Communication Charging Stations The AC charging station (commonly known as "slow charging") charges the battery of an electric vehicle through a car charger, and the charging process requires the car charger to convert AC power into DC power. This method of charging is relatively slow, but it causes less battery damage. 1. Lower cost: Due to the simple converter of AC charging stations and the fact that the main power conversion is completed inside the car charger, the cost of AC charging stations is lower compared to DC charging stations. 2. Easy installation and maintenance: AC charging stations have a small volume, flexible installation, and relatively low requirements for ground bearing capacity, making them easy to install and use in personal residences, commercial buildings, and other places. 3. Wide applicability: Almost all electric vehicles support AC charging, making AC charging stations more widely applicable. However, the charging efficiency of communication charging stations is relatively low, usually taking several hours to complete the charging process, making them more suitable for situations where people stay at home or work for a long time. Advantages and Applications of DC Charging Stations Flow charging stations (also known as "fast charging stations") directly convert alternating current into direct current to quickly charge the batteries of electric vehicles with high power. This method can bypass the limitations of car chargers and directly charge the battery, resulting in a faster charging speed. 1. Fast charging speed: The most significant advantage is the fast charging speed. For consumers in urgent need of quick power replenishment, DC charging stations can charge electric vehicles to around 80% of their capacity within 30 minutes, greatly improving charging efficiency. 2. High efficiency conversion: Due to the fact that the power conversion process is completed inside the charging station, energy transmission losses are reduced and charging efficiency is improved. 3. High degree of intelligence: DC charging stations are generally equipped with more advanced control systems and user interfaces, which can provide more charging management and payment functions. The main disadvantage of DC charging stations is their high cost and relatively strict installation and maintenance requirements. Therefore, they are more commonly installed in public charging stations and fast charging networks. Comparison of Core Differences between DC Charging Stations and AC Charging Stations 1. Charging speed DC charging station: Due to its high charging power, usually above 60kW, there are other specifications such as 30kW, 120kW, 160kW, 360kW, 380kW, etc. Supercharging stations can even reach 800kW, so the charging speed is faster. In an ideal situation, the battery can be fully charged within 20-150 minutes; AC charging station: The charging power of AC charging stations is generally low, usually around 7kW, and there are other specifications such as 3.5kW and 11KW, so the charging time is longer, usually taking 8-15 hours to fully charge the battery; 2. Charging pile cost DC charging station: The manufacturing and installation costs of DC charging stations are relatively high, requiring large volume transformers and AC-DC conversion modules, which are much more expensive than AC charging stations; Communication charging station: The manufacturing and installation cost of communication charging stations is relatively low, the structure is simple, the volume is small, and it is easy to install and popularize; 3. Volume of charging station Due to the large number of internal components, the volume of the DC pile is relatively large, and its charging gun head has nine holes; The modules of the communication station are relatively few and the volume is small, with a 7-hole charging gun head; 4. Impact on batteries DC charging station: DC charging stations may cause certain damage to the battery during the charging process, as their output current is high and they release more heat during charging. High temperatures may lead to a sudden decrease in battery capacity and damage to the battery cells; AC charging station: Due to its low charging power and long charging time, AC charging stations do not cause excessive impact on the battery, which is beneficial for extending battery life; 5. Protection level DC charging station: Generally, DC charging stations are more commonly used in complex outdoor scenarios, facing more complex weather such as rain and snow, with higher protection levels, generally above IP54 protection level. AC charging station: Generally, DC charging stations are more commonly used in indoor garage scenarios, facing relatively simple environments and requiring lower levels of protection. 6. Adapt to the scene DC charging station: Due to its fast charging speed, DC charging stations are suitable for installation in charging stations next to highways, taxi and bus stops, and other scenarios that require high charging time. Communication charging station: Communication charging stations are suitable for installation in residential areas, parking lots, and other places to meet daily charging needs, especially suitable for night charging because users can charge at night and the battery will be fully charged the next day when using the vehicle. How to choose between DC charging station and AC charging station? Choosing the appropriate type of charging station should be based on the following considerations: 1. Charging speed requirement: If you often need fast charging, a DC charging station is a more suitable choice. But if most of the time is spent parking at home or work for a long time, then AC charging stations can meet the demand. 2. Installation site: Considering the installation cost and the adaptability of charging piles to the environment, individual residences and small businesses are more suitable for installing AC charging piles. 3. Budget: If the budget is sufficient, it is possible to consider equipping DC charging stations in public places to attract more electric vehicle owners to use them. However, if the budget is limited, AC charging stations are a more economical choice. Current situation and development trend of charging pile market The market concentration of DC charging piles is relatively high, with the market share of major operators reaching 85.2%, and the number of public DC piles continues to grow, but the proportion has decreased. Communication charging stations: Due to their low cost and ease of promotion, communication charging stations are commonly built in residential areas, parking lots, and other places. With the continuous expansion of the electric vehicle market, both DC charging piles and AC charging piles will be more widely used. In the future, with the advancement of technology and the decrease of costs, both will improve in charging speed, intelligence level, cost-effectiveness, and other aspects. At the same time, new charging technologies such as wireless charging will gradually mature, bringing more and more convenient choices for electric vehicle users.

What is the best size to choose for civilian transformers? When choosing a civilian transformer, the appropriate capacity depends on the specific usage scenario and requirements. ‌ For household appliance transformers, the general recommendation is to choose a transformer that can carry 80% of the rated power of the equipment. This is because inductive loads (such as motors) have a large instantaneous current when starting, so using 70% of the rated power is sufficient. If it is only used for a short period of time, even smaller power can be selected. For example, choosing a 220/110V transformer with a power range of 50-60W can meet the needs of most households, while also providing appropriate power surplus. ‌ For larger civil buildings or residential areas, the selection of transformers needs to consider the reliability of power supply, initial investment costs, and operational economics. When considering transformer capacity, it should be calculated and determined based on actual load. For example, for the calculation of electricity load in residential buildings, the unit index method needs to be combined with coefficients for calculation. For example, a coefficient of 0.6 can be applied to 30 households per unit, a coefficient of 0.5 can be applied to 60 households per building, and a coefficient of 0.4 can be selected for transformers in 240 households. In addition, as mentioned in typical examples, for the case of 900 households, using a three-phase distribution coefficient of 0.26 and a power consumption of 6kW per household, it is appropriate to calculate the transformer capacity with a load of 1404kW. ‌ In summary, when choosing a civilian transformer, the appropriate transformer capacity should be determined based on specific usage scenarios and requirements. For household use, a transformer of 50-60W can be selected; For larger residential areas or civil buildings, it is necessary to calculate the specific electricity load and select the appropriate transformer capacity to ensure the reliability, economy, and environmental friendliness of power supply.

What Is A Transformer? Power supply design is an unavoidable issue in current hardware product design. In the previous article, we have discussed several types of DCDC converters. Today, we will explore another low loss buck boost scheme: transformers. A transformer is an electromagnetic component of a circuit used to change the alternating voltage. It can convert one AC voltage into another through electromagnetic conversion while keeping the power basically unchanged. Application of Transformers In the power system, transformers are widely used for increasing or decreasing voltage. It can be used for electrical isolation, significantly improving system safety and reducing the risk of electric shock; The use of transformers also achieves grounding system separation, which can effectively suppress common mode noise; Provided DC isolation to protect sensitive circuits; Simultaneously achieving voltage conversion and impedance matching while isolating; Restricting the scope of fault propagation and improving system reliability; Improved electromagnetic compatibility, helping to meet EMC requirements; Support multiple winding applications and adapt to complex system requirements; It can also be used for special applications such as signal coupling, phase adjustment, and harmonic suppression. These advantages make transformers an indispensable key component in fields such as power, industry, healthcare, and communication, providing solid guarantees for the safety, efficiency, and reliability of modern electrical systems and greatly promoting the development of modern power systems. Working Principle of Transformer The working principle of transformers is based on the law of electromagnetic induction. Its electromagnetic structure consists of two or more coils wound around the same iron core. In practical structures, there will be insulation materials used between windings and between windings and iron cores, as well as between the casing and cooling system. When AC current passes through the primary coil, an alternating magnetic field is generated in the iron core. This alternating magnetic field will induce voltage in the secondary coil. By adjusting the turns ratio of the primary and secondary coils, different output voltages can be obtained. Usually, transformers have more than one circuit, for example, single-phase transformers have two circuits, while three-phase transformers have six circuits. The iron cores and winding materials of different transformers vary greatly. Julin Technology's PowerExpert supports simple and flexible custom transformer construction. Custom transformers can be built using winding, core or non-linear core, and winding binding (K_Magnatic) devices. The ideal magnetic core supports setting magnetic permeability, cross-sectional area and length, while the nonlinear magnetic core supports setting shape parameters, magnetic domain wall bending constant, hysteresis loss coefficient, saturation magnetization intensity and other coefficients. The magnetic core and winding are set to belong to the same transformer through winding binding devices. Build a simple custom transformer using PowerExpert software, where the winding has 5 turns and 10 turns, as shown in the following figure: Perform transient simulation, and the simulation results obtained are shown in the following figure:

Fibre soft and slender substance with length to diameter ratio at least 10:1,  the cross-sectional area less than 0.05mm2. For textile fibers, the ratio of length to diameter is generally greater than 1000:1.  About textile fibers: Natural fiber, such as cotton, hemp, wool, silk and so on; Chemical fiber refers to natural or synthetic polymers as raw materials, through chemical methods and mechanical processing made as fiber.   1) According to the source of raw material: Regenerated fibre and Synthetic fibres Regenerated fibre also be called as synthetic fiber, using natural polymers or lost textile processing value of fiber raw materials through a series of chemical treatment and mechanical processing be fiber again, the chemical composition of the fiber and original polymer is alomost same. Including Regenerated cellulose fibre (such as viscose fiber, copper ammonia fiber), Regenerated protein fiber  (such as soy protein fiber, peanut protein fiber), regenerated inorganic fiber (such as glass fiber, metal fiber)  and regenerated organic fiber (such as chitin fiber, seaweed gum fiber). Synthetic fiber is made of natural low molecular compounds such as petroleum, coal, limestone, natural gas, salt, air, water and some agricultural and sideline products as raw materials, through chemical synthesis and processing be fibers. There are seven common types of synthetic fibers: polyester fiber (polyester), polyamide fiber (nylon), polyacrylonitrile fiber (acrylic fiber), polyvinyl formaldehyde fiber (vinylon), polypropylene fiber (polypropylene), polyvinyl chloride fiber (chlorinated fiber) and polyurethane elastic fiber (spandex), etc.      2) Classification by morphological structure: Continuous filament and Staple fibre Continuous filament  During chemical fiber manufacturing process, spinning fluid (fusant or melt) after spinning forming and post-processing, the length of fiber is caiculated in kilometers is called chemical fiber filament. Chemical fiber filaments can be divided into monofil, multifilaments, twisted fibers, double twisted fibers, cord fibers and Textured filament. Monofilament: A single continuous fiber of very long length. Multifilaments: A filament composed of two or more single filaments joined together. Complex filaments of chemical fibers are generally composed of 8 to 100 single fibers. Twist yarn: twist Multifilaments  becomes twist yarn. Double twist yarn: Two or more strands of twist yarn are combined to be double twist yarn. Cord wire: composed of more than one hundred to several hundred single fibers, used to make tire cord fabric. Textured filament yarn: The chemical fiber filament is deformed and processed so that it has the appearance characteristics of curling, spiral, ring and so on, showing fluffy and flexible filament. Staple fibre The product of the chemical fiber is cut into few centimeters to dozen centimeters in length, it is called staple fiber. According to the different cut length, staple fibers can be divided into cotton type, wool type and medium long staple fibers. The length of Cotton type fibre is 30 ~ 40mm, the linear density is about 1.67dtex, the fiber is fine, similar to cotton. The length of Wool type fibre is 70 ~ 150mm, the linear density is 3.3 ~ 7.7dtex, the fiber is thicker, similar to wool; Mid fibre has a length of 51 ~ 65mm and a linear density of 2.2 ~ 3.3dtex, between cotton type and wool type.   3)  Classification by fiber manufacturing method Chemical fibers can be divided into two categories according to the basic manufacturing methods,  melt spinning fibers and solution spinning fibers (i.e. dry spinning fibers and wet spinning fibers). Melt spinning is polymer melt is pressed out of the spinneret hole, melt is solidified into silk in the surrounding air (or water). Dry-spinning is polymer concentrated solution is pressed out from the spinneret hole form as trickle, solvent evaporates rapidly in hot medium and solidifies into silk.  Wet spinning is polymer concentrated solution is pressed out of the spinneret hole and solidified into silk in a coagulation bath.   4) Classification by composition within a single fiber Single-component fibers: Fibers composed of the same polymer are called single-component fibers, and most conventional fibers are single-component fibers, such as polyester. Multicomponent fibers:Fibers composed of two or more polymers are called multicomponent fibers, such as acrylic fibers.  Composite fiber:the components are arranged regularly along the fiber axis and form a continuous interface fiber. Blended fiber: components are randomly dispersed or more evenly mixed fiber   5) Classification by fiber difference Differential fibre: chemical fiber that has undergone chemical or physical changes to differentiate it from conventional fibers. Such as profiled fiber, composite fiber, microfiber, easily dyed fiber, flame retardant fiber, hydrophilic synthetic fiber, colored fiber and anti-pilling fiber. Functional fibre: except existing properties of the fiber, attach some special functions. Such as conductive fiber, optical fiber, ion exchange fiber, ceramic particle fiber, temperature control fiber, radiation fiber, bioactive fiber, biodegradable fiber, can produce negative ion fiber, antibacterial and deodorizing fiber. High-performance fibre: special fibers with a strength of 17.7cNhttps://www.yarnfabricdyemachine.comdtex and a modulus of 441.5cNhttps://www.yarnfabricdyemachine.comdtex. Such as carbon fiber, aromatic polyamide fiber, polybenzimidazole fiber, polyphenylene sulfide fiber and ultra-high molecular weight polyethylene fiber.   Whether it is natural fiber or chemical fiber products: Hank yarn, package yarn, fabric, top, loose fiber etc., Wuxi Shin Tong Yunn Machinery can provide  corresponding dyeing equipment(hank yarn dyeing machine, cone yarn dyeing machine, fabric dyeing machine, garment dyeing machine etc.) and finishing equipment(yarn extractorhttps://www.yarnfabricdyemachine.comfabric dehydrator, yarn dryeing machine, fabric drying machine etc.), welcome to visit our factory and website.  

Knitting products are widely used in the three major fields of wear, decoration and industrial use, forming a relatively complete knitting industry chain. Functional knitting products include sports apparel, medical assistance products, military defense supplies & fashion apparel developed through the integration of high-tech material with knitting technology, which not only meet the increasingly diverse needs of people,but also innovate in combination with cutting-edge technology. With the rapid development of science and technology,various functional & diversified products combining traditional textile technology emerge in endless stream. According characteristics of knitted fabrics, functional knitting products, as an important product combining textile technology and scientific innovation, are gradually becoming new focus of the development of the textile industry. At the same time,with the development of green functional knitting products, functional knitwear is not only the result of technological innovation, but also embodiment of market demand and sustainable development trends. 1. Hygroscopic and perspiratory knitted products The wetting process of sweat involves the contact and penetration between sweat and fiber and fabric surface. The water in this process mainly depends on the capillary action between fiber and yarn to move, and the water finally evaporates rapidly through the fabric surface to achieve the quick-drying effect. Moisture wicking fabric can effectively reduce the retention time of sweat on the skin surface, keep the skin dry and reduce the growth of bacteria, improve the wearer's comfort. Related applications in sports products include cycling clothing, yoga clothing, sports underwear, sports shoes, etc.   2. Antibacterial knitting products Antibacterial knitted fabrics can realize antibacterial function through five ways: natural antibacterial fiber, regenerative antibacterial fiber, synthetic antibacterial fiber, modified antibacterial fiber and antibacterial agent finishing and processing. On this basis, combined with organizational structure design, product performance can be further optimized and bacterial growth can be effectively inhibited. At present, antibacterial knitting products are used in daily use, medicine and other fields.   3. Uv protection knitted products Uv protection can be achieved through functional yarns or functional finishing (sunscreen reagents, functional coatings). Anti-ultraviolet function products can effectively block ultraviolet radiation, make the wearer feel more comfortable, extend the service life of the product, in outdoor, use, automotive materials and other fields have been developed and applied.   4. Waterproof knitting products Waterproof knitted products are made by functional yarn or special finishing technology, which can effectively prevent water from penetrating into the interior of knitted products, prevent stains, fading and fabric deformation caused by water, and improve the durability and quality stability of products. At present, waterproof functional knitting products are used in outdoor sports, daily protection and other fields.   5. Electromagnetic shielding knitting products Electromagnetic shielding knitting products are used in daily use, military defense and other scenarios. Electromagnetic shielding fabric is an excellent shielding material made of functional yarn with both light weight, flexibility and strength. It is widely used because of its thin and light, good surface adhesion and a large number of grid structures. At present, the design principle of electromagnetic shielding fabrics is mainly to use the conductivity of the material to metalize the surface of the fabric to form a metal conductive layer, or to make conductive filament and conductive yarn first, and then weave into the fabric, so that the metal conductive grid is formed inside the fabric.   6, Smart responsive knitting products Intelligent response technology provides more possibilities for the development of functional knitting products, in addition to the traditional clothing field, intelligent response knitting products can also be applied to medical, sports, military and other fields. Through intelligent components, knitting products can achieve a variety of functions such as health monitoring, position tracking, and temperature regulation.   7. Warm knitting products Warm knitting products can be used to form a static air layer inside the fabric through the selection of functional fibers or yarns with warmth, combined with the tissue design, to reduce heat loss, and can also be adjusted by the weaving process parameters (such as density, thickness, etc.) to improve the thermal performance of the fabric. A wide range of warm knit products, including warm underwear, warm coats, warm knee pads and so on. The composite fiber prepared by special process not only makes up for some performance shortcomings of natural fiber, but also shows superior thermal performance. The knitted products prepared by it can also have other properties, such as antibacterial, antistatic, breathable and so on, while having warmth.   8. Stab-proof and cut-proof knitting products Stab-proof and cut-proof products are widely used in military, medical, sports and other fields, including anti-cut neck guard, stab-proof clothing, stab-proof vest, cut-proof gloves and other products. Among them, flexible stab-proof clothing can not only meet the requirements of special occupations for protective performance, but also suitable for daily wear because of its comfort, which is a research hotspot in recent years. Bulletproof textiles made from high-strength fibers such as ultra-high molecular weight polyethylene (UHMWPE) or aramid provide some protection against projectiles such as shrapnel and ammunition fragments. The traditional full overlay design limits the energy absorption of the composite during ballistic impact. In contrast, the checkerboard design formed by polycarbonate (PC) film and aramid can effectively improve the ballistic performance. The bullet-proof performance of the checkerboard PC film also increases with the increase of the number of spacer layers.   9. Other functional knitting products Other functional knitting products also include fire retardant, anti-static, anti-mosquito and other products. Among them, the development of antistatic knitting products mainly involves material selection, fabric structure design, application of antistatic finishing technology and many other aspects. Wuxi Shin Tong Yunn Machinery Technology Co., Ltd fabric dyeing machine DD636 high temperature long tube jet fabric dyeing machine and DD636B series is suitable for dyeing conventional knitted fabrics and functional technology knitted fabrics. Welcome to visit our factory and show the knitted fabric dyeing machine for you.

Bobbin dyeing technology: subjective reasons cause of non-recurrence of yarn through cone yarn dyeing are roughly as below:  winding quality, dye selection, dyeing process, operating factors, management problems, etc.   WINDING QUALITY INFLUENCES REPRODUCIBILITY (1) Bobbin weight: When dyeing by immersion method, the depth of apparent color depends largely on the weight ratio of dye to yarn. In generally, only the number of bobbin is counted when the yarn is put on the cone yarn carrier, no longer weighed again. Therefore, the winding weight determines weight of loading yarn, be weighted after soft winding. Many factory production practices have proved that even without a fixed length meter, it is completely possible to weigh each bobbin and control the weight within the range of ± 1%. Some dyeing plants use "card" to measure the outside diameter, but because of the large error, it is not suitable. The different size of package yarn after dyeing also will get color difference betweent bobbin yarn.   (2) Bobbin winding density: The winding density of soft bobbin with direct relationship to resistance of circulation of dyeing liquor . High density, high resistance. Resistance magnitude affects shape of dyeing liquor circulation resistance curve, then affects main circulation pump, affects the circulation flow of the dye fluid, the circulation frequency of dye fluid and number of cycles within specified time are changed, so the amount of dye on yarn is changed, causing the color of yarn to be deep or shallow. When some bobbin winding density is too small, sometimes the yarn will be out of the "groove", sometimes caused "collapse", the dye liquid will get "short circuit", not only the yarn is washed and dyed unevenly, but also rest bobbin dye liquid circulation will be reduced and cause light color.   (3)"Hole exposure" : Because the bobbin and the beam coil are full of holes for the dye to travel through, when the bobbin is not properly wound, or the reciprocating distance is not enough, "hole exposure" will occur. When dyeing, because the warp shaft is placed vertically in the main body of high pressure cone yarn dyeing machine, if winding is too loose, the yarn will fall due to gravity after wetting at sometimes, resulting in upper "hole exposure". The dye liquor will "short circuit" from the "exposed hole", not only wash the yarn on the end of the bobbin, but also affect the flow capacity of other bobbin.

PRETREATMENT INFLUENCES REPRODUCIBILITY Many dyeing plants don't pay attention to pre-treatment. Actually, many problems in dyeing processing because of ingnoring do enough pre-treatment. Impurity removal degree, whiteness, pH value after washing, purification of hydrogen peroxide after bleaching, amount of alkali carried by mercerized yarn, different tension affect gloss. When dyeing bobbin yarn, pre-treatment, dyeing and post-treatment are carried out in the same high pressure bobbin dyeing machine, and the pre-treatment effect is also different. Generally, the dyeing factory pays more attention to force determination and weighing of dyes，but less attention is paid to the force determination and weighing of other chemicals.  Caustic soda, soda ash, hydrogen peroxide is not analyzed, only calculated according to instructions, dye liquor are rarely titrated. So pre-treatment effect is different, causes difference of color depth and hue. As mentioned, paying attention to compatibility, compatibility, sensitivity and quality of dyestuff, in order to ensure reproducibility.   RATIONALITY OF DYEING TECHNOLOGY INFLUENCES REPRODUCIBILITY Although selecting appropriate dye, the dyeing process is designed not reasonable, there also be cylinder differences.  Such as temperature design, heating rate, holding time, amount of additives and feeding method scientificity, the rationality of post-treatment process design will affect the dyeing amount of dyestuff resulting in color difference. Such as adding reactive dye solid alkali, fixation and hydrolysis of reactive dyes have a lot to do with the pH value of dye bath, the scientific feeding method is to maintain the Pu value at a fixed value (such as pH value is 11.5), which is related to the feeding method and feeding rate, if one-time feeding or feeding fast and slow all will cause pH fluctuations, amount of fixation and hydrolyzed dyes is different, finally eflects the different shades of light.  

In order to fully improve the added value of colored product, except add patten, high-count yarn & blended yarn and special dyeing process can also be used to achieve a unique style of colored cloth. Pure cotton blended yarn-dyed fabric: soft feel, breathable, strong water absorption. In recent years, it has been favored by the majority of consumers. Color cotton by mixing cotton, carding cotton, spinning, weaving to eliminate color difference, it is convenient production. RAW MATERIAL REQUIREMENT 1. Raw cotton requirement After the raw cotton dyeing, the color cotton should be mixed, combed, spun, and finally wovenhttps://www.yarnfabricdyemachine.comknitted, and the requiements of color difference is not strictly, so it is suitable for any variety of raw cotton. 2. Dye compound The dyestuffs and auxiliaries are used for cotton bleaching and dyeing: with fine particles and soluble in water, good diffusion and permeability.   DYEING In order to obtain better color mixing effect of cotton textiles, pay attention to two important points in raw cotton dyeing: remove natural impurities of loose fiber and spinnability of dyed cotton fiber. 1. Pretreatment Cotton fibers contain many symbionts, such as waxes, nitrogen, pectin, minerals and natural pigments, cottonseed shells, etc. The existence of these symbionts will seriously affect the wettability of cotton fiber, making it difficult to dyeing, so it must be removed first. The pre-treatment of raw cotton dyeing: boiling and bleaching and related washing. The purpose is to remove cotton impurities, fruit gum and natural pigments that hinder dyeing. After boiling and fully washing, it is necessary to check whether the concentration of alkali, residual hydrogen peroxide and whiteness meet the process requirements or not. Generally, the whiteness of the cotton fiber after pre-treatment are consistent, and the pH value is neutral. 2. Raw cotton dyeing Using direct dyes and reactive dyes, considering the color fastness and convenience of use, using reactive dyes is better, because reactive dyes with bright color, complete chromatography and a certain wet processing fastness. The process control is stable and appropriate additives, the reproducibility of dyeing is good, cylinder (batch) difference is less. In addition, the use of reactive dyes dyeing, if it is combination of color, it is best to choose a better compatibility of reactive dyes for collocation. 3.  Postprocessing Post-treatment is an important part of raw cotton dyeing, after dyeing should do fully washed and soaping treatment, in order to remove impurities and residual chemical additives on the cotton fiber. When washing, detergent with strong decontamination ability and good permeability should be used to enhance the cleaning effect of the inner layer of the fiber. After washing, in order to increase the spinnability, softening agent should be added for softening treatment to improve the lubricity of the fiber.   DEHYDRATOR AND DRYING After dehydration , the color cotton treated by softener is easy to loose, after production practice, the moisture return after drying is controlled at 6 to 8, with soft feel and good spinnability.   SPINNING TECHNOLOGY After raw cotton dyeing, the cotton fiber lost  spinnability processing of boiled and bleached, removed wax and oil, feel becomes coarse. In order to improve this situation, one the one hand, adding softener to loosen the cotton and improve its spinnability after full washing. On the other hand, reasonable cotton matching with raw cotton. There are two kinds of cotton matching between colored cotton and raw cotton: One is carried out in the cotton cleaning process, the color cotton and the raw cotton after grabbing cotton, mixing cotton, opening into rolls and  strips, finally spinning and knitted or woven fabric; Another one is processing during combining, the color sliver with the raw cotton sliver, through two strips, so that it is mixed into a strip, finally spinning and weaving or knitting. Through experiment, the former method is better, color cotton and raw cotton through mixing , carding, spinning and weaving, basically eliminate color difference.No matter which one is adopted, the mixing ratio of color cotton and raw cotton is generally controlled at about 0.5-10 percent, spinnability is better, don't  change the original production technology.   DYEING INTANCE 9.7tex red cotton using Shin Tong Yunn high pressure dyeing machine, bath ratio 1:15, internal and external cycle time ratio 5:3. 1. Process flow: raw cotton- boiling-washing-dyeing-washing-soft treatment-dehydration-drying - packing 2. pretreatment Process prescription, (ghttps://www.yarnfabricdyemachine.comL)NaOH(36 'Be) 5 stabilizer FT 2OH202(27.5%) 8,  Temperature 120℃ penetrant JFc 1.0 time 120min. 3. Raw cotton dyeing (bright red) process prescription, (ghttps://www.yarnfabricdyemachine.comL) Peregal O 015 reactive brilliant orange X-Gn 3. 575N a2CO 3 25 Bright Red X一3B 6．i25Na2SO． 70。 4. Soft treatment Process prescription, (ghttps://www.yarnfabricdyemachine.comL) softener HC-8 5. Dyeing cotton by spinning process Cotton blending - roll - carding - strip - roving - fine yarn - raw cotton - fine cotton   NOTE: DF241 series high pressure cone yarn dyeing machine is suitable doing pre-treatment, post processing and dyeing of raw cotton(cotton fiber), only need change the carrier form.