Yearly Archives: 2024

　　Bolt looseness is common, but if you don’t pay attention, it will often cause equipment vibration, component damage, and even casualties. How to tighten a small nut has always been a long-lasting topic in mechanical design. Today, let’s talk about the most basic method of fixing nuts in work.As it happens, many people are killed Anchorage agent for mines And bring more benefits, make it flourish, and promote the industry greatly. https://www.chinatianlong.com/

　　In general, we analyze the bolt fracture from the following four aspects:

　　First, the quality of bolts

　　Second, the pre-tightening torque of bolts

　　Third, the strength of bolts

　　Fourthly, the fatigue strength of bolts.

　　In fact, most cases of bolt fracture are caused by looseness, specifically, it is damaged due to looseness. Because the situation of bolt loosening and breaking is basically the same as that of fatigue fracture, finally, we can always find the reason from the fatigue strength. In fact, the fatigue strength is so great that we can’t imagine it, and the fatigue strength is not used at all in the use of bolts.

　　01

　　The bolt fracture is not due to the tensile strength of the bolt.

　　Take a M20〜80 8.8-grade high-strength bolt as an example. Its weight is only 0.2kg, and its minimum tensile load is 20t, which is as high as 100,000 times its own weight. Under normal circumstances, we only use it to fasten 20kg parts, and only use one thousandth of its maximum capacity. Even under the action of other forces in the equipment, it is impossible to exceed 1,000 times the weight of the parts, so the tensile strength of threaded fasteners is sufficient and it is impossible to damage them because of insufficient strength of bolts.

　　02

　　The fracture of bolts is not due to the fatigue strength of bolts.

　　Threaded fasteners can be loosened only 100 times in the transverse vibration loosening experiment, but they need to be vibrated repeatedly for one million times in the fatigue strength experiment. In other words, the threaded fastener is loose when using one ten thousandth of its fatigue strength, and we only use one ten thousandth of its great capacity, so the loosening of the threaded fastener is not due to the fatigue strength of the bolt.

　　03

　　The real reason for the damage of threaded fasteners is looseness.

　　When the threaded fastener is loosened, it generates huge kinetic energy mv2, which directly acts on the fastener and equipment, causing the fastener to be damaged. After the fastener is damaged, the equipment cannot work in a normal state, further causing the equipment to be damaged.

　　When the fastener is subjected to axial force, the thread is damaged and the bolt is pulled off.

　　When the fastener is subjected to radial force, the bolt is cut and the bolt hole is oval.

　　04

　　Choosing thread locking mode with excellent locking effect is the fundamental solution to the problem.

　　Take hydraulic hammer as an example. The weight of GT80 hydraulic hammer is 1.663 tons, and its side bolts are 7 sets of M42 bolts of grade 10.9. The tensile force of each bolt is 110 tons, and the pre-tightening force is half of the tensile force, and the pre-tightening force is as high as 300 to 400 tons. However, the bolt will break, and now it is ready to be changed to M48 bolt. The fundamental reason is that the bolt locking cannot be solved.

　　When a bolt breaks, it is easy for people to conclude that the strength is not enough, so most of them adopt the method of increasing the strength grade of the bolt diameter. This method can increase the pre-tightening force of the bolt, and its friction force is also increased. Of course, the anti-loosening effect can also be improved, but this method is actually a non-professional method, and its investment is too large and its income is too small.

　　In short, the bolt is: “If you don’t loosen it, it will break.”

　　Cause analysis of bolt looseness

　　The threaded connection is designed according to the self-locking condition: ψ ＋ρv, and the friction pair generated in the threaded pair makes the bolt self-lock to tighten the bolt, so the connection will not loosen automatically under static load. However, under impact, vibration, variable load and great temperature change, the friction force f of the screw pair will decrease or disappear instantly. If this phenomenon occurs repeatedly, the connecting bolt will gradually loosen. After the threaded fastener is loosened, the kinetic energy mv2 is generated, and the fastener subjected to axial force, the thread is destroyed and the bolt is pulled off. Fasteners subjected to radial force, bolts are cut and bolt holes are broken.

　　Bolt locking principle: limit the relative motion between screw pairs or increase the difficulty of relative motion.

　　Introduction of common anti-loosening methods

　　There are three commonly used methods for locking bolts: friction locking, mechanical locking and permanent locking. Among them, mechanical locking and friction locking are called detachable locking, while permanent locking is called non-detachable locking.

　　01

　　Friction locking

　　1. Spring gasket locking

　　The anti-loosening principle of the spring washer is that after the spring washer is flattened, the spring washer will generate a continuous elastic force, so that the threaded connection pair between the nut and the bolt will maintain a friction force continuously and generate a resistance moment, thus preventing the nut from loosening. At the same time, the sharp corner at the opening of the spring washer is embedded into the surface of the bolt and the connected piece respectively, thus preventing the bolt from rotating relative to the connected piece.

　　2. Lock the top nut (double nut)

　　3. Self-locking nut locking

　　One end of the nut is made into a non-circular convergent or radially convergent after being slit. When the nut is tightened, the closure expands, and the screwing threads are pressed by the elastic force of the closure.

　　4. Locking of elastic ring nut

　　Fiber or nylon is embedded in the thread to increase friction. The elastic ring also plays a role in preventing liquid leakage.

　　02

　　Mechanical locking

　　Locking of groove nut and cotter pin

　　2. Stop gasket

　　After the nut is tightened, the single-ear or double-ear stop washer is bent and attached to the side of the nut and the connected part respectively to realize locking.

　　3. Locking of series steel wire

　　Use low-carbon steel wire to penetrate the holes in the head of each screw, and connect the screws in series to brake each other.

　　03

　　Permanent locking

　　Commonly used permanent locking are: spot welding, riveting, bonding, etc. This method mostly destroys threaded fasteners during disassembly and cannot be reused.

　　In addition, there are other ways to prevent loosening, such as: coating liquid adhesive between screwing threads, embedding nylon rings at the end of nuts, riveting and locking. Mechanical locking and friction locking are called detachable locking, while permanent locking is called non-detachable locking.

　　1, punching method to prevent loose

　　After the nut is tightened, the thread is damaged at the end of the thread.

　　2. Adhesive Locking-Nut Locking Solution

　　Apply the nut locking liquid to the bolt tightening position, and then screw on the nut. After self-curing, the locking effect is good.

　　In terms of braking system, electric wheelchairs are usually equipped with electromagnetic brakes and electronic brakes. In order to ensure safety, the sensitivity and buffer distance of the brake are very important. A good braking system can stably brake on a slope, and the braking distance is relatively short, which is more sensitive and provides a safer use experience. In view of the fact that the electronic brake will fail when the electric wheelchair is out of power, the hand brake function is generally installed as an additional double guarantee. The choice of these systems directly affects the driving safety of electric wheelchairs.More importantly, put 電動輪椅 It is imperative for us to make thorough analysis and maximize its social function. https://www.hohomedical.com/collections/light-weight-wheelchair

　　Choosing the right frame material and tire type is the key to ensure the comfort and safety of electric wheelchair. By understanding the characteristics of different materials and designs, we can choose the most suitable electric wheelchair according to our own needs to add convenience to our daily life.

　　Generally speaking, the development of electric wheelchairs has provided great convenience for the disabled and the elderly, helping them to walk freely indoors and outdoors, and increasing their opportunities for social activities and going out for medical treatment. Secondly, it provides the ability to move independently. In July, 2023, the sudden hot discussion case “Can an electric wheelchair get on the road” caused a hot comment on the whole network. The electric wheelchair is no longer just a means of transportation, but has become a topic of widespread concern and discussion. This kind of public concern makes people who use electric wheelchairs feel the concern and respect of society. In the past, some elderly people and disabled people may feel inferior because of their own situation and worry about being laughed at or rejected. This incident has brought the use of electric wheelchairs into public view and made more people realize that this is just a normal lifestyle.

　　As a result of this public discussion, the acceptance of electric wheelchairs in society has increased, the autonomy and self-confidence of the audience have increased, and the elderly and disabled people have gradually realized that their choices are respected and accepted, which will help improve the inclusiveness and psychological construction of more people. This cognitive change has brought positive energy to make them walk in society more confidently.

　　With the continuous development of industrial technology, pump equipment plays an increasingly important role in industrial production. In the fields of chemical engineering, medicine, food, etc., pump equipment, as an important tool for conveying media, has a significant impact on production efficiency and quality. In recent years, with the strengthening of environmental awareness and the increasing demand for safety production, enterprises have become more strict in product selection. In the post pandemic era, the global economy is in a downturn, and business operations are facing even more severe challenges. How to reduce costs and increase efficiency, improve production efficiency and product quality has become an urgent problem for enterprises to solve. As one of the important transportation tools, the selection and optimization of pump equipment have also become an important way for enterprises to improve production efficiency and reduce costs.understand Chemical filter In order to better serve customers and reflect the core competitiveness of products. http://www.luoyuan108.com/

　　The KG series of coaxial acid alkali resistant pumps we have launched are carefully developed to meet the needs of enterprises. This pump has multiple unique design and technological advantages, which can reduce costs, improve production efficiency, and ensure production safety for chemical enterprises. Let’s learn about the features and advantages of this pump together.

　　01 Product Features

　　The KG series coaxial acid alkali resistant pump is a pump designed for the chemical industry, which has the following characteristics:

　　1. Wide applicability: This pump can be applied to media with various chemical properties, and its applicable temperature is below 85 ≧ for FRPP and PVDF, depending on the different chemical properties. At the same time, choosing different pump body materials can resist strong acids and alkalis, as well as the chemical properties used in fluorination series.

　　2. Unique shaft seal design: adopting Teflon Bellows Seal self cooling type, selecting shaft seal materials Sic, Carbon, Ceramic according to various chemical properties. Compared to other similar products, the shaft seal design of this pump is more unique, which can effectively ensure the service life and operational safety of the pump.

　　3. The rear cover is a combination type: easy to assemble, with no cooling circulation circuit design, and cannot be used idle. The rear cover of the pump adopts a combination design, which is easy to assemble and does not require a cooling circulation circuit, ensuring the safe operation of the pump.

　　4. Low noise: The pump is made of high-quality materials and exquisite craftsmanship, with advantages such as low noise and low vibration. It ensures stable operation of the pump while reducing noise interference during the production process.

　　5. High reliability: The pump adopts advanced production technology and precise mechanical processing, and has undergone multiple rigorous tests and verifications to ensure the reliability and stability of the product.

　　02 Product specifications and parameters

　　03 Advantage Comparison

　　Compared with traditional pumps, the advantages of KG series coaxial acid alkali resistant pumps are:

　　Low noise and low vibration: Designed with advanced fluid analysis technology, the pump’s noise and vibration are minimized, ensuring a quiet and stable production site.

　　Low energy consumption: The design and optimization of pumps can greatly reduce energy consumption, thereby saving energy costs.

　　Long lifespan: The shaft seal of the pump adopts a Teflon Bellows Seal self cooling design, which can greatly extend the service life of the pump.

　　No need for additional cooling circulation circuit: The rear cover of the pump is a combination type, easy to assemble, without a cooling circulation circuit design, and cannot be used idle, making the use of the pump more convenient and reliable.

　　04 Application Fields

　　The KG series coaxial acid alkali resistant pumps are widely used in industries such as chemical, pharmaceutical, electronics, and environmental protection for the transportation, filtration, and circulation of acid alkali liquids. For example:

　　Chemical industry: In fields such as organic synthesis and hydrocarbon cracking, acid-base liquids are inevitable, which requires reliable acid-base pumps for transportation.

　　Pharmaceutical industry: In the process of drug synthesis and formulation, a certain amount of acid-base liquid is required, and the role of acid-base pump is particularly important.

　　Electronics industry: In the production of semiconductors, LCD displays, and other products, various corrosive and electroplating solutions are required. These liquids have strong corrosiveness and volatility, and high-quality corrosion-resistant pumps are needed. The FRPP and PVDF materials of KG series pumps can withstand the corrosion of these chemicals, and adopt a unique Teflon Bellows Seal self cooling shaft seal design, effectively avoiding the damage of chemical corrosion to the pump.

　　Overall, the KG series coaxial acid alkali resistant pumps have the advantages of high efficiency, corrosion resistance, safety, and stability, and are widely used in various industries. Our company will continue to be committed to developing high-quality and efficient pumps, providing high-quality products and services for various industries.

　　It is the energy source of electric wheelchairs, which can be divided into lead-acid batteries and lithium batteries. The voltage of electric wheelchairs is generally 24v. The different ah capacity of batteries directly affects the overall weight, endurance and service life of wheelchairs. With the continuous development of lithium battery technology, modern electric wheelchairs usually use lithium batteries as the power source.Today, people are interested in 電動輪椅 There are also many dependencies, and the expectations for products are getting higher and higher. https://www.hohomedical.com/collections/light-weight-wheelchair

　　Lithium batteries have the advantages of high energy density, light weight and fast charging speed, which can provide a longer cruising range. There are also 6AH lithium batteries in the market that meet the standards of air boarding. People with disabilities and mobility difficulties can travel with portable electric wheelchairs and batteries.

　　If the 20ah lead-acid battery is compared with the 20ah lithium battery, the lithium battery has a lighter weight and a longer battery life, and the life of the lithium battery is relatively long, about twice the life of the lead-acid battery, but the cost of lithium battery will be higher. Lead acid, on the other hand, is relatively more economical, and there are many after-sales points of electric vehicles under the domestic battery brands such as Chaowei, which is convenient for maintaining batteries and replacing carbon brushes, and can meet the needs of users for long-term use.

　　At present, lithium battery electric wheelchairs are mainly used in portable electric wheelchairs, which are relatively inferior to lead-acid in battery life. The later replacement cost is also high. Here, you can refer to the approximate cruising range of the battery collected by Xiaobian. The battery life will be different due to different road conditions, different people’s weights and continuous exercise time.

　　After more than a year of repeated tests and cooperation with seven other collaborators, the high-performance steel team of Shanghai University School of Materials successfully developed the world’s first 19.8-grade ultra-high-strength bolt known as the world’s strongest fastener.In the industry, DIN934 Has been a leader in the industry, but later came from behind but never arrogant, low-key to adhere to quality. https://www.chinatianlong.com/

　　Through the optimization of materials and heat treatment process, the tensile strength of 16.8 and 19.8 grade bolts at room temperature meets 1600~1770MPa and 1900~2070MPa respectively.

　　The results of shear test (according to GJB 3376-1998) show that the shear force of grade 16.8 and grade 19.8 bolts reaches 97KN and 115KN respectively.

　　The tensile fatigue strength test at room temperature (according to GJB 3376-1998 and GJB715.30A-2002, the load ratio =0.1) shows that the developed fastener meets the fatigue life requirements (the average fatigue life is not less than 65,000 times, and the single fatigue life is not less than 45,000 times).

　　The results of delayed fracture resistance test (according to GJB 715.12-1990, the constant tensile stress was kept for 96 hours in atmospheric environment) showed that the bolt did not break during the test time, and no cracks were found on the bolt surface and thread after unloading. The comprehensive performance of the newly developed ultra-high strength bolt meets the service requirements.

　　Class 16.8 and 19.8 fasteners in kind (specifications are MJ8〜1〜50)

　　Under the same clamping force, the ultra-high strength fastener can reduce its weight and increase the installation space by reducing its own size, so it can optimize the function and volume of the connected parts, so as to achieve the goal of overall weight reduction and performance optimization of the equipment.

　　So what is a high strength bolt? What is the strength of high-strength bolts? Sister Jin brought you here today to find out.

　　one

　　What is a high strength bolt?

　　High-Strength Friction Grip Bolt, literally translated as: high-strength friction preload bolt, abbreviated as HSFG. It can be seen that the high-strength bolt mentioned in Chinese construction is the abbreviation of high-strength friction pre-tightening bolt. In daily communication, only the words “Friction” and “Grip” are briefly mentioned, but it has caused many engineers and technicians to understand the basic definition of high-strength bolts, resulting in misunderstandings.

　　Myth 1:

　　Bolts with material grade over 8.8 are “high strength bolts”?

　　The core difference between high-strength bolts and ordinary bolts is not the strength of the materials used, but the form of stress. The essence is whether to apply pre-tightening force and use static friction to resist shear.

　　In fact, there are only two kinds of high-strength bolts (HSFG BOLT) mentioned in British Standard Specification and American Standard Specification (BS EN 14399/ASTM-A325&ASTM-490), while ordinary bolts include 4.6, 5.6, 8.8, 10.9, 12.9, etc. (BS 3692 11, Table 2) It can be seen that the strength of materials is not the key to distinguish high-strength bolts from ordinary bolts.

　　2?

　　Where is the strength of high-strength bolts?

　　According to GB50017, calculate the tensile and shear strength of a single ordinary bolt (Class B) with Grade 8.8 and a high-strength bolt with Grade 8.8.

　　Through calculation, we can see that the design values of tensile strength and shear strength of ordinary bolts are higher than those of high-strength bolts under the same grade.

　　So where is the “strength” of high-strength bolts?

　　In order to answer this question, it is necessary to study the law of elastic-plastic deformation of two kinds of bolts from the design working state, and understand the limit state of design failure.

　　Stress-strain curves of ordinary bolts and high-strength bolts under working conditions

　　Limit state of design failure

　　Ordinary bolt: the screw itself has plastic deformation exceeding the design allowable, and the screw is sheared.

　　For ordinary bolted connections, there will be relative slip between the connecting plates before they begin to bear shear force, and then the bolt rod will contact with the connecting plates, which will cause elastic-plastic deformation and bear shear force.

　　High-strength bolt: The static friction between the effective friction surfaces is overcome, and the two steel plates are relatively displaced, which is considered as failure in design.

　　When high-strength bolts are connected, the friction bears the shear force first. When the load increases to the point where the friction force is not enough to resist the shear force, the static friction force is overcome and the connecting plates slide relatively (limit state). However, although it is damaged at this time, the bolt rod is in contact with the connecting plate, and it can still bear the shear force by using its own elastic-plastic deformation.

　　Myth 2:

　　High bearing capacity is high strength bolt?

　　From the calculation of a single bolt, it can be seen that the design strength of high-strength bolt in tension and shear is lower than that of ordinary bolt. The essence of its high strength is that during normal operation, the joint is not allowed to slip, that is, the elastic-plastic deformation is small and the joint stiffness is large.

　　It can be seen that the joints designed with high-strength bolts may not necessarily save the number of bolts under the given design node load, but they have small deformation, high stiffness and high safety reserve. It is suitable for the main beam, and other positions that require greater joint stiffness, which conforms to the basic seismic design principle of “strong joints and weak members”.

　　The strength of high-strength bolts lies not in the design value of their own bearing capacity, but in the high stiffness, high safety and strong damage resistance of their designed joints.

　　three

　　Comparison between high strength bolts and ordinary bolts

　　Ordinary bolts and high-strength bolts have great differences in construction inspection methods because of their different design stress principles.

　　The mechanical performance requirements of ordinary bolts of the same grade are slightly higher than those of high-strength bolts, but high-strength bolts have one more acceptance requirement for impact work than ordinary bolts.

　　The marking of ordinary bolts and high-strength bolts is the basic method to identify bolts of the same grade on site. Because the values of torque calculation for high-strength bolts in British and American standards are different, it is necessary to identify the bolts of the two standards.

　　Ordinary bolts are about 70% of the price of high-strength bolts. Combined with the comparison of their acceptance requirements, it can be concluded that the premium part should be to ensure the impact energy (toughness) performance of materials.

　　The treatment of corrosive liquids has always been a common challenge in many industrial fields. To solve this problem, it is particularly important to choose a pump suitable for transporting corrosive media. The KB series self-priming acid alkali pump is a high-performance pump that combines multiple advantages and is suitable for various complex working environments such as acid and alkali. The following are the characteristics, performance, applications, and selection references of KB series self-priming acid alkali pumps. We hope that through this article, everyone can have a deeper understanding of KB series self-priming pumps.In order to grow rapidly, chemical pump Do not hesitate to change the strategy and rearrange the products, so as to obtain unexpected results. http://www.luoyuan108.com/

　　Product Features

　　1. Unique shaft seal design – The interior adopts Teflon Bellow Seal self cooling design, effectively protecting the pump shaft and improving cooling effect. This design ensures stable operation of the pump under harsh conditions and improves its service life.

　　2. Self suction design – The self suction force is particularly strong, reaching up to 20ft, effectively avoiding liquid backflow inside the pump. At the same time, the equipped check valve design further prevents liquid backflow, ensuring the stable operation of the pump.

　　3. Strong acid resistance, strong alkali resistance, and strong corrosion resistance – made of materials such as CFRPP and PVDF, it can resist the erosion of various corrosive media such as strong acids and bases, ensuring the long-term service life of the pump.

　　4. The integrated design of the rear cover, shaft seal shield, and foot seat makes maintenance and assembly more convenient, while also enhancing the overall aesthetics of the pump.

　　5. The inlet needs to be equipped with a bottom valve – the bottom valve can effectively block the suction of foreign objects and protect the safe operation of the pump.

　　6. The outlet needs to be equipped with a check valve – a check valve can prevent instantaneous backflow during shutdown, avoiding damage to the pump body and pump idling.

　　Specification parameters

　　Flow range: 200-900 (L/min)

　　Head range: 6-32 (m)

　　Materials used: FRPP, PVDF

　　Motor power: 0.75-7.5 (kw)

　　Temperature range: 0-75 ≧ (PP, FRPP) 0-90 ≧ (PVDF)

　　Usage and maintenance

　　1. Before using the pump, please ensure that the bottom valve is installed correctly to prevent foreign objects from being sucked into the pump.

　　2. Before starting the pump, please check if the inlet and outlet valves are open to ensure the normal operation of the pump.

　　3. It is recommended to regularly inspect and maintain the pump to ensure its normal operation and extend its service life.

　　4. Regularly replace bearings and seals to avoid wear and leakage.

　　5. If any abnormal situation is found during the operation of the pump, it should be stopped immediately for inspection.

　　Application Fields

　　The KB series self-priming acid and alkali resistant pumps are widely used in chemical, pharmaceutical, food, environmental protection and other fields. In these fields, KB pumps can be used to transport various corrosive media such as acids, bases, salts, etc. For example, in the chemical industry, KB pumps can be used to transport corrosive acid liquids such as sulfuric acid and hydrochloric acid; In the pharmaceutical industry, KB pumps can be used to transport various drug solutions; In the food industry, KB pumps can be used to transport various acid-base solutions and corrosive food additives.

　　Other fields: In addition to the above fields, KB pumps can also be applied in environmental protection, oil, natural gas and other fields. For example, in the field of environmental protection, KB pumps can be used to treat pollutants such as industrial wastewater and acidic gases. In the field of oil and gas, KB pumps can be used to transport various corrosive media, such as acidic gases, alkaline solutions, etc.

　　Selection suggestions

　　When choosing a self-priming pump, the following factors need to be considered:

　　1. Medium characteristics: including the corrosiveness, viscosity, density, and other properties of the medium, in order to select suitable materials and structures.

　　2. Process parameters: including flow rate, head, pressure, and other parameters to select the appropriate model and power.

　　3. Environmental conditions: including temperature, humidity, air quality, etc., in order to select the appropriate protection level and motor configuration.

　　4. Application scenarios: including the industry of use, purpose, installation method, etc., in order to select suitable functions and structures.

　　5. Based on the above factors, it is possible to choose the appropriate KB pump model and configuration for the application. In addition, it is recommended to consider factors such as brand and quality assurance when selecting pumps to ensure long-term stable operation and service life.

　　In summary, the KB series self-priming acid alkali pump is a high-performance, corrosion-resistant, and easy to maintain pump. Its unique shaft seal design and self-priming design make it perform well in handling corrosive liquids. Whether in the chemical, pharmaceutical, or other industrial fields, the KB series self-priming acid and alkali resistant pumps are a reliable choice. If you need more information about the KB series self-priming acid alkali pump, please feel free to contact our professional team, and we will be happy to serve you.

　　The English word for Screw is screw. The meaning of this word has changed greatly in recent hundreds of years. At least in 1725, it means “mating”.At the same time, Railway fittings It is no longer a relatively unfamiliar industry, and it enters the public’s sight more and more frequently, gaining more attention and recognition. https://www.chinatianlong.com/

　　The application of the thread principle can be traced back to 220 BC, when the Greek scholar Archimedes created the spiral water lifting tool.

　　In the 4th century A.D., Mediterranean countries began to apply the principle of bolts and nuts to the press for wine making. At that time, the external threads were all wrapped around a cylindrical bar with a rope, and then carved according to this mark, while the internal threads were often formed by hammering with soft materials wrapped around the external threads.

　　Around 1500, in the sketch of thread processing device drawn by Italian Leonardo da Vinci, there was an idea of using mother screw and exchange gear to process threads with different pitches. Since then, the method of mechanical thread cutting has developed in European watch manufacturing industry.

　　In 1760, the British brothers J. Wyatt and W. Wyatt obtained a patent for cutting wooden screws with a special device. In 1778, an Englishman, J. ramsden, made a thread cutting device driven by a worm gear pair, which could process long threads with high precision. In 1797, H. Maudslay, an Englishman, turned metal threads with different pitches on the lathe improved by him, which laid the basic method for turning threads.

　　In the 1820s, Maudslay produced the first batch of taps and dies for thread processing.

　　At the beginning of the 20th century, the development of automobile industry further promoted the standardization of threads and the development of various precise and efficient thread processing methods. Various automatic opening die heads and automatic shrinking taps were invented one after another, and thread milling began to be applied.

　　In the early 1930s, thread grinding appeared.

　　Although the thread rolling technology was patented in the early 19th century, it developed slowly because of the difficulty in mold manufacturing. It was not until the Second World War (1942 ~ 1945) that the demand of ammunition production and the development of thread grinding technology solved the precision problem of mold manufacturing, and it achieved rapid development.

　　Threads are mainly divided into connection threads and transmission threads.

　　For connecting threads, the main processing methods are tapping, threading, turning, rolling and rubbing.

　　For transmission thread, its processing methods are mainly: rough turning-grinding, cyclone milling-rough turning, etc.

　　Today, let’s take a look at the various processing methods of threads with Xiao Bang and see which method is better.

　　When choosing the frame material, we should not only consider the material itself, but also pay attention to the design and function of the frame. For example, folding electric wheelchairs bring great convenience to those who are inconvenient to bend over or have disabled hands, so that they no longer have to work hard to fold electric wheelchairs; The conventional electric wheelchair is comprehensive, affordable and stable, suitable for a wider range of users.Not only does it perform well in data, 電動輪椅價錢 In the market share, it is also gradually expanding, so that more people can benefit. https://www.hohomedical.com/collections/light-weight-wheelchair

　　Front wheel and rear wheel: The design of front wheel and rear wheel of electric wheelchair directly affects its flexibility and shock absorption. Usually, an electric wheelchair has four wheels, two of which are front wheels (universal wheels) and the other two are rear wheels (driving wheels). The smaller the front wheel, the more flexible the wheelchair is, which is suitable for turning flexibly in a narrow space. However, the smaller front wheels are easy to fall into ditches or ground cracks when facing them, which affects the driving experience. In addition, the size of the front wheel also affects the climbing ability of the electric wheelchair. The larger front wheel makes it easier for the wheelchair to climb the stairs, which makes it more convenient for users in their daily lives.

　　Shock absorption: the choice of tires is also very important in shock absorption. The tires of electric wheelchairs are usually divided into pneumatic tires and solid tires. Pneumatic tires have good shock absorption, and it is not easy to feel bumpy when passing through ditches and ridges, while solid tires will feel strong shock when facing uneven roads. In addition, some electric wheelchairs are equipped with special shock absorbers, which makes the driving more stable. These designs not only improve the comfort of wheelchairs, but also make users safer when they are outdoors.

　　In industries such as pharmaceuticals, biopharmaceuticals, and fine chemicals, filtering raw drug solutions is a crucial step. This stage not only affects the purity and quality of the product, but also relates to the safety and stability of the production process. In order to meet the strict requirements of these industries, based on years of practical experience and comprehensive reference to advanced filtration technologies at home and abroad, we have successfully developed a KTA series chemical liquid filter designed specifically for liquid filtration.from Plating filter Looking at the development prospects, the future will always bring positive effects. http://www.luoyuan108.com/

　　The characteristics and advantages of this filter lie in its efficient filtration performance, diverse selection of filter materials, and excellent corrosion resistance and sealing performance. These features ensure that the KTA series chemical liquid filters perform excellently in various pharmaceutical, biological, and fine chemical production scenarios.

　　Product Introduction

　　The KTA series chemical liquid filter is a highly versatile filtration device that uses advanced filtration technology to efficiently filter impurities and foreign objects in the liquid, ensuring the purity and safety of the liquid. This product mainly consists of a filter element, a filter housing, and sealing materials, among which the filter element is the core component used to intercept impurities in the drug solution.

　　Product features and advantages

　　1. This series of filters is injection molded from PP, PVDF, and FRPP materials, suitable for filtering most chemical solutions. PP material filters are widely used in the pharmaceutical industry, which have the characteristics of strong corrosion resistance, non toxicity, odorlessness, and high temperature resistance, and can effectively resist the corrosion of most chemical solutions.

　　2. Efficient filtration: The KTA series chemical liquid filter adopts a fine filter screen, which can filter out small particles, bacteria and other impurities in the liquid, ensuring the purity of the liquid.

　　3. The filter materials include filter cartridge lock cap type, pressure plate type, filter paper type, starfruit type, filter tube type, and filter bag type, which can be selected and interchangeable. Different filter materials can adapt to pharmaceutical companies with different industries and filtration needs. For example, filter cartridge lock cap and pressure plate filter materials can filter most of the medicinal liquids, filter paper filter materials can filter high viscosity medicinal liquids, and filter tube filter materials can filter high-temperature medicinal liquids.

　　4. Good sealing performance and easy cleaning: The unique sealing design avoids leakage and ensures the safety of the production process; The filter element is detachable, easy to clean, and can meet the production needs of different enterprises.

　　5. According to customer requirements, the upper and lower plates can be processed into complete sets of PP solid plates to meet the needs of customers in high-pressure environments. This feature makes the KTA series chemical liquid filter more widely used, not only in conventional pharmaceutical and chemical production, but also in processes that require high pressure.

　　Product specifications and parameters

　　Model Number: KTA Chemical Liquid Filter

　　Filter capacity range: 15-430 (L/min)

　　Main materials: PP, PVDF, FRPP

　　Temperature range: 0-70 ＜ C

　　Filtering accuracy: 0.5um-500um

　　Filter material: Universal standard size

　　Sealing material: high-quality rubber

　　Application industry

　　The KTA series chemical liquid filters are widely used in industries such as pharmaceuticals, biological products, and fine chemicals. In these industries, it is mainly used for filtering chemical drugs, biological product culture media, buffer solutions, and other fine chemical raw materials to ensure the purity and safety of materials during the production process.

　　In the pharmaceutical industry, this filter can be used to filter extracts of antibiotics, biochemical drugs, and traditional Chinese medicine.

　　In the bioproducts industry, it can be used to filter materials such as culture media and buffer solutions to ensure the purity and safety of the products.

　　In the fine chemical industry, it can be used to filter various fine chemical raw materials, such as dyes, coatings, and pesticides.

　　The KTA series chemical solution filter is also widely used in the electroplating industry, and can be applied to multiple processes such as electroplating solution filtration, electroplating wastewater treatment, electroplating tank solution circulation filtration, and electroplating additive filtration to ensure the quality and stability of electroplating products. It is an ideal choice for the electroplating industry.

　　In short, the KTA series chemical liquid filters are designed specifically for industries such as pharmaceuticals, biological products, and fine chemicals. It uses a variety of filter materials, which are corrosion-resistant and have good sealing performance, suitable for different filtration needs. Special filter design, easy to clean and maintain. Whether in drug extraction, biological product filtration, or fine chemical production, the KTA series filters can provide solid quality assurance.

　　Choose KTA to bring efficiency improvement and reliable guarantee to your production process. If you are struggling with filtration issues and looking for a high-performance, professional grade chemical liquid filter, then our KTA series is undoubtedly your ideal choice.

　　The English word for Screw is screw. The meaning of this word has changed greatly in recent hundreds of years. At least in 1725, it means “mating”.Only by working together can we turn wedge anchor The value of the play out, the development of the supply market needs. https://www.chinatianlong.com/

　　The application of the thread principle can be traced back to 220 BC, when the Greek scholar Archimedes created the spiral water lifting tool.

　　In the 4th century A.D., Mediterranean countries began to apply the principle of bolts and nuts to the press for wine making. At that time, the external threads were all wrapped around a cylindrical bar with a rope, and then carved according to this mark, while the internal threads were often formed by hammering with soft materials wrapped around the external threads.

　　Around 1500, in the sketch of thread processing device drawn by Italian Leonardo da Vinci, there was an idea of using mother screw and exchange gear to process threads with different pitches. Since then, the method of mechanical thread cutting has developed in European watch manufacturing industry.

　　In 1760, the British brothers J. Wyatt and W. Wyatt obtained a patent for cutting wooden screws with a special device. In 1778, an Englishman, J. ramsden, made a thread cutting device driven by a worm gear pair, which could process long threads with high precision. In 1797, H. Maudslay, an Englishman, turned metal threads with different pitches on the lathe improved by him, which laid the basic method for turning threads.

　　In the 1820s, Maudslay produced the first batch of taps and dies for thread processing.

　　At the beginning of the 20th century, the development of automobile industry further promoted the standardization of threads and the development of various precise and efficient thread processing methods. Various automatic opening die heads and automatic shrinking taps were invented one after another, and thread milling began to be applied.

　　In the early 1930s, thread grinding appeared.

　　Although the thread rolling technology was patented in the early 19th century, it developed slowly because of the difficulty in mold manufacturing. It was not until the Second World War (1942 ~ 1945) that the demand of ammunition production and the development of thread grinding technology solved the precision problem of mold manufacturing, and it achieved rapid development.

　　Threads are mainly divided into connection threads and transmission threads.

　　For connecting threads, the main processing methods are tapping, threading, turning, rolling and rubbing.

　　For transmission thread, its processing methods are mainly: rough turning-grinding, cyclone milling-rough turning, etc.

　　Today, let’s take a look at the various processing methods of threads with Xiao Bang and see which method is better.