oneNot only does it perform well in data, left thread anchor bolt In the market share, it is also gradually expanding, so that more people can benefit. https://www.chinatianlong.com/

　　

　　Classification of fasteners and related accessories

　　

　　1. Fasteners:

　　

　　Bolts, studs, nuts, screws, washers, wood screws, tapping screws, pins, rivets, retaining rings, assemblies and connecting pairs, welding nails, innovative and non-standard products;

　　

　　2. Equipment:

　　

　　Molding equipment: cold heading machine, cold extrusion molding machine, heading machine, nailing machine, etc.

　　

　　Thread forming equipment: thread rolling machine, thread rolling machine, tapping machine, etc.

　　

　　Heat treatment equipment: industrial furnace, tempering line, high and medium frequency induction heating equipment, material annealing furnace, etc.

　　

　　Surface treatment equipment: phosphating line, oxidation line, zinc plating line, dacromet production line, etc.

　　

　　Auxiliary equipment: grinding machine, slotting machine, vibrating plate, marking machine, etc.

　　

　　Testing equipment and devices: hardness tester, material tension and compression tester, microscope, etc.

　　

　　3, tooling:

　　

　　Bolt forming die: including cutting die, upper die (pre-die, fine die, trimming die, etc.) and lower die (cold upsetting die, reducing die, ejector pin, etc.)

　　

　　Nut forming die: including cutting die, punch, punch, hole die, forming die, thimble, etc.

　　

　　Thread forming tools: thread rollers, thread washboards, taps, etc.

　　

　　4, surface treatment:

　　

　　Surface treatment process: electroplating, blackening, heat treatment, hot dip zinc, phosphating, mechanical plating and dacromet.

　　

　　Auxiliary materials: brightener, cleaning agent, antirust agent and degreasing agent.

　　

　　5. Raw materials:

　　

　　Medium carbon steel, low carbon steel, alloy steel, stainless steel (including wire, bar, plate, pipe, etc.)

　　

　　2

　　

　　The meaning of bolt performance grade

　　

　　The performance grades of bolts used for steel structure connection are divided into more than 10 grades, such as 3.6, 4.6, 4.8, 5.6, 6.8, 8.8, 9.8, 10.9 and 12.9. Among them, bolts of grade 8.8 and above are made of low-carbon alloy steel or medium-carbon steel and are heat-treated (quenched and tempered), which are generally called high-strength bolts, and the rest are generally called ordinary bolts.

　　

　　The bolt performance grade label consists of two parts of numbers, which respectively represent the nominal tensile strength value and yield ratio value of the bolt material. For example, a bolt with performance grade 4.6 means:

　　

　　1. The nominal tensile strength of bolt material reaches 400MPa;

　　

　　2. The yield ratio of bolt material is 0.6;

　　

　　3. The nominal yield strength of the bolt material reaches 400X0.6=240MPa, and the performance grade is 10.9. After heat treatment, the material can reach:

　　

　　1. The nominal tensile strength of bolt material reaches 1000MPa;

　　

　　2. The yield ratio of bolt material is 0.9;

　　

　　3. The nominal yield strength of bolt material reaches 1000X0.9=900MPa.

　　

　　The meaning of bolt performance grade is an international standard. Bolts with the same performance grade have the same performance regardless of the difference of material and origin, so only performance grade can be selected in design.

　　

　　The so-called 8.8 and 10.9 strength grades mean that the shear stress grades of bolts are 8.8GPa and 10.9Gpa.

　　

　　8.8 Nominal tensile strength 800N/MM2 Nominal yield strength 640N/MM2.

　　

　　Generally, the strength of bolts is expressed by “X.Y”.

　　

　　X*100= tensile strength of this bolt,

　　

　　X*100* (Y/10 )= yield strength of this bolt.

　　

　　(Because according to the marking: yield strength/tensile strength =Y/10)

　　

　　Such as 4.8.

　　

　　Then the bolt’s

　　

　　The tensile strength is 400MPa.

　　

　　The yield strength is: 400*8/10=320MPa. In addition, stainless steel bolts are usually marked as A4-70 and A2-70, and the meaning is otherwise explained.

　　

　　three

　　

　　magnanimity; tolerance

　　

　　There are mainly two types of length measurement units in the world today. One is metric, with the measurement units of meters (m), centimeters (cm) and millimeters (mm), which are widely used in Europe, China and Japan, and the other is English, with the measurement unit of inch, which is equivalent to the old city inch in China, and is widely used in the United States, Britain and other European and American countries.

　　

　　1. Metric measurement: (decimal system)

　　

　　1m =100 cm=1000 mm

　　

　　2. English measurement: (octal)

　　

　　1 inch =8 minutes 1 inch =25.4 mm3/8 00×25.4 =9.52

　　

　　3, 1/4 0 of the following products use serial numbers to indicate their address diameter, such as:

　　

　　4#5#6#7#8# 10# 12#

　　

　　four

　　

　　screw thread

　　

　　1. Thread is a shape with uniform spiral protrusions on the cross section of solid outer surface or inner surface. According to its structural characteristics and uses, it can be divided into three categories:

　　

　　(1) Ordinary thread: the tooth shape is triangular, which is used to connect or fasten parts. Ordinary threads are divided into coarse thread and fine thread according to pitch, and the connection strength of fine thread is higher.

　　

　　(2) Transmission thread: the tooth shapes include trapezoid, rectangle, saw and triangle.

　　

　　(3) Sealing thread: used for sealing connection, mainly including pipe thread, taper thread and taper pipe thread.

　　

　　Second, the thread matching grade:

　　

　　Thread fit is the size of looseness or tightness between screwed threads, and the level of fit is the prescribed combination of deviation and tolerance acting on internal and external threads.

　　

　　(1) For unified English thread, there are three thread grades for external thread: 1A, 2A and 3A, and three grades for internal thread:

　　

　　1B, 2B and 3B, all of which are clearance fit. The higher the grade number, the tighter the fit. In English thread, the deviation is only specified as Grade 1A and Grade 2A, the deviation of Grade 3A is zero, and the grade deviation of Grade 1A and Grade 2A is equal.

　　

　　The greater the number of grades, the smaller the tolerance.

　　

　　Classes 1, 1A and 1B, very loose tolerance classes, which are suitable for tolerance fit of internal and external threads.

　　

　　Grade 2, 2A and 2B are the most common thread tolerance grades specified by English series mechanical fasteners.

　　

　　Grade 3, 3A and 3B, which are screwed to form the tightest fit, are suitable for fasteners with tight tolerances and are used for the key design of safety.

　　

　　4. For external threads, there is a fit tolerance for Grade 1A and 2A, but not for Grade 3A. The tolerance of Class 1A is 50% greater than that of Class 2A and 75% greater than that of Class 3A. For internal threads, the tolerance of Class 2B is 30% greater than that of Class 2A. Class 1B is 50% larger than class 2B and 75% larger than class 3B.

　　

　　(2) Metric thread. There are three thread grades for external thread: 4h, 6 H and 6g, and three thread grades for internal thread: 5H, 6h and 7H. (The thread accuracy grade of Japanese standard is divided into I, II and III, which is usually Grade II) In metric thread, the basic deviation between H and H is zero. The basic deviation of G is positive, and the basic deviations of E, F and G are negative. As shown in the figure:

　　

　　1. H is the commonly used tolerance zone position of internal thread, which is generally not used as surface coating or extremely thin phosphating layer. The basic deviation of G position is used in special occasions, such as thick coating, which is rarely used in general.

　　

　　2. G is commonly used to plate a thin coating of 6-9um. For example, the bolt required by the product drawing is 6h, and the thread before plating is 6g tolerance zone.

　　

　　3. It is best to combine the thread fit into H/g, H/h or G/H. For refined fastener threads such as bolts and nuts, the standard recommends 6H/6g fit.

　　

　　(3), thread marking

　　

　　Three, the main geometric parameters of self-tapping and self-drilling thread:

　　

　　(1) The major diameter/tooth outer diameter (d1) is the imaginary cylinder diameter with overlapping thread crests. The major diameter of the thread basically represents the nominal diameter of the thread size.

　　

　　(2) Small diameter/root diameter (d2): it is the imaginary cylinder diameter with overlapping thread roots.

　　

　　(3) Pitch (P): refers to the axial distance between adjacent teeth corresponding to two points on the meridian. Pitch is expressed by the number of teeth per inch (25.4mm) in the British system.

　　

　　There are many choices of seat back cushion and cushion materials for electric wheelchairs in the market, mainly including mesh cotton and honeycomb materials. The choice of these materials will affect the comfort and ventilation of the seat. For example, compared with honeycomb materials, mesh cotton is more breathable and less likely to store heat. A comfortable wheelchair cushion should conform to the contour of human buttocks, providing good support and wrapping.As can be seen from the new data, 電動輪椅 The market influence is also growing, and the product share is also relatively increasing, which has great potential in the future. https://www.hohomedical.com/collections/light-weight-wheelchair

　　

　　In addition, the cushion also needs to have air permeability and good hygroscopicity to ensure the dryness of the skin surface. Considering that the user’s long-term use of local skin temperature will accelerate the cell metabolism rate, which will make the skin sweat and ulcer when immersed in a humid environment for a long time.

　　

　　The quality of seat back cushion is mainly judged by fabric smoothness, tension and routing details. Laymen can also distinguish the advantages and disadvantages of the seat back cushion by carefully observing these details.

　　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.Without exception, chemical pump Our customers are willing to purchase their products, because high quality is the concept of their 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.

　　oneIn view of the actual needs of society, rock bolts We need to change some original problems to better serve the society and benefit people. https://www.chinatianlong.com/

　　

　　Classification of fasteners and related accessories

　　

　　1. Fasteners:

　　

　　Bolts, studs, nuts, screws, washers, wood screws, tapping screws, pins, rivets, retaining rings, assemblies and connecting pairs, welding nails, innovative and non-standard products;

　　

　　2. Equipment:

　　

　　Molding equipment: cold heading machine, cold extrusion molding machine, heading machine, nailing machine, etc.

　　

　　Thread forming equipment: thread rolling machine, thread rolling machine, tapping machine, etc.

　　

　　Heat treatment equipment: industrial furnace, tempering line, high and medium frequency induction heating equipment, material annealing furnace, etc.

　　

　　Surface treatment equipment: phosphating line, oxidation line, zinc plating line, dacromet production line, etc.

　　

　　Auxiliary equipment: grinding machine, slotting machine, vibrating plate, marking machine, etc.

　　

　　Testing equipment and devices: hardness tester, material tension and compression tester, microscope, etc.

　　

　　3, tooling:

　　

　　Bolt forming die: including cutting die, upper die (pre-die, fine die, trimming die, etc.) and lower die (cold upsetting die, reducing die, ejector pin, etc.)

　　

　　Nut forming die: including cutting die, punch, punch, hole die, forming die, thimble, etc.

　　

　　Thread forming tools: thread rollers, thread washboards, taps, etc.

　　

　　4, surface treatment:

　　

　　Surface treatment process: electroplating, blackening, heat treatment, hot dip zinc, phosphating, mechanical plating and dacromet.

　　

　　Auxiliary materials: brightener, cleaning agent, antirust agent and degreasing agent.

　　

　　5. Raw materials:

　　

　　Medium carbon steel, low carbon steel, alloy steel, stainless steel (including wire, bar, plate, pipe, etc.)

　　

　　2

　　

　　The meaning of bolt performance grade

　　

　　The performance grades of bolts used for steel structure connection are divided into more than 10 grades, such as 3.6, 4.6, 4.8, 5.6, 6.8, 8.8, 9.8, 10.9 and 12.9. Among them, bolts of grade 8.8 and above are made of low-carbon alloy steel or medium-carbon steel and are heat-treated (quenched and tempered), which are generally called high-strength bolts, and the rest are generally called ordinary bolts.

　　

　　The bolt performance grade label consists of two parts of numbers, which respectively represent the nominal tensile strength value and yield ratio value of the bolt material. For example, a bolt with performance grade 4.6 means:

　　

　　1. The nominal tensile strength of bolt material reaches 400MPa;

　　

　　2. The yield ratio of bolt material is 0.6;

　　

　　3. The nominal yield strength of the bolt material reaches 400X0.6=240MPa, and the performance grade is 10.9. After heat treatment, the material can reach:

　　

　　1. The nominal tensile strength of bolt material reaches 1000MPa;

　　

　　2. The yield ratio of bolt material is 0.9;

　　

　　3. The nominal yield strength of bolt material reaches 1000X0.9=900MPa.

　　

　　The meaning of bolt performance grade is an international standard. Bolts with the same performance grade have the same performance regardless of the difference of material and origin, so only performance grade can be selected in design.

　　

　　The so-called 8.8 and 10.9 strength grades mean that the shear stress grades of bolts are 8.8GPa and 10.9Gpa.

　　

　　8.8 Nominal tensile strength 800N/MM2 Nominal yield strength 640N/MM2.

　　

　　Generally, the strength of bolts is expressed by “X.Y”.

　　

　　X*100= tensile strength of this bolt,

　　

　　X*100* (Y/10 )= yield strength of this bolt.

　　

　　(Because according to the marking: yield strength/tensile strength =Y/10)

　　

　　Such as 4.8.

　　

　　Then the bolt’s

　　

　　The tensile strength is 400MPa.

　　

　　The yield strength is: 400*8/10=320MPa. In addition, stainless steel bolts are usually marked as A4-70 and A2-70, and the meaning is otherwise explained.

　　

　　three

　　

　　magnanimity; tolerance

　　

　　There are mainly two types of length measurement units in the world today. One is metric, with the measurement units of meters (m), centimeters (cm) and millimeters (mm), which are widely used in Europe, China and Japan, and the other is English, with the measurement unit of inch, which is equivalent to the old city inch in China, and is widely used in the United States, Britain and other European and American countries.

　　

　　1. Metric measurement: (decimal system)

　　

　　1m =100 cm=1000 mm

　　

　　2. English measurement: (octal)

　　

　　1 inch =8 minutes 1 inch =25.4 mm3/8 00×25.4 =9.52

　　

　　3, 1/4 0 of the following products use serial numbers to indicate their address diameter, such as:

　　

　　4#5#6#7#8# 10# 12#

　　

　　four

　　

　　screw thread

　　

　　1. Thread is a shape with uniform spiral protrusions on the cross section of solid outer surface or inner surface. According to its structural characteristics and uses, it can be divided into three categories:

　　

　　(1) Ordinary thread: the tooth shape is triangular, which is used to connect or fasten parts. Ordinary threads are divided into coarse thread and fine thread according to pitch, and the connection strength of fine thread is higher.

　　

　　(2) Transmission thread: the tooth shapes include trapezoid, rectangle, saw and triangle.

　　

　　(3) Sealing thread: used for sealing connection, mainly including pipe thread, taper thread and taper pipe thread.

　　

　　Second, the thread matching grade:

　　

　　Thread fit is the size of looseness or tightness between screwed threads, and the level of fit is the prescribed combination of deviation and tolerance acting on internal and external threads.

　　

　　(1) For unified English thread, there are three thread grades for external thread: 1A, 2A and 3A, and three grades for internal thread:

　　

　　1B, 2B and 3B, all of which are clearance fit. The higher the grade number, the tighter the fit. In English thread, the deviation is only specified as Grade 1A and Grade 2A, the deviation of Grade 3A is zero, and the grade deviation of Grade 1A and Grade 2A is equal.

　　

　　The greater the number of grades, the smaller the tolerance.

　　

　　Classes 1, 1A and 1B, very loose tolerance classes, which are suitable for tolerance fit of internal and external threads.

　　

　　Grade 2, 2A and 2B are the most common thread tolerance grades specified by English series mechanical fasteners.

　　

　　Grade 3, 3A and 3B, which are screwed to form the tightest fit, are suitable for fasteners with tight tolerances and are used for the key design of safety.

　　

　　4. For external threads, there is a fit tolerance for Grade 1A and 2A, but not for Grade 3A. The tolerance of Class 1A is 50% greater than that of Class 2A and 75% greater than that of Class 3A. For internal threads, the tolerance of Class 2B is 30% greater than that of Class 2A. Class 1B is 50% larger than class 2B and 75% larger than class 3B.

　　

　　(2) Metric thread. There are three thread grades for external thread: 4h, 6 H and 6g, and three thread grades for internal thread: 5H, 6h and 7H. (The thread accuracy grade of Japanese standard is divided into I, II and III, which is usually Grade II) In metric thread, the basic deviation between H and H is zero. The basic deviation of G is positive, and the basic deviations of E, F and G are negative. As shown in the figure:

　　

　　1. H is the commonly used tolerance zone position of internal thread, which is generally not used as surface coating or extremely thin phosphating layer. The basic deviation of G position is used in special occasions, such as thick coating, which is rarely used in general.

　　

　　2. G is commonly used to plate a thin coating of 6-9um. For example, the bolt required by the product drawing is 6h, and the thread before plating is 6g tolerance zone.

　　

　　3. It is best to combine the thread fit into H/g, H/h or G/H. For refined fastener threads such as bolts and nuts, the standard recommends 6H/6g fit.

　　

　　(3), thread marking

　　

　　Three, the main geometric parameters of self-tapping and self-drilling thread:

　　

　　(1) The major diameter/tooth outer diameter (d1) is the imaginary cylinder diameter with overlapping thread crests. The major diameter of the thread basically represents the nominal diameter of the thread size.

　　

　　(2) Small diameter/root diameter (d2): it is the imaginary cylinder diameter with overlapping thread roots.

　　

　　(3) Pitch (P): refers to the axial distance between adjacent teeth corresponding to two points on the meridian. Pitch is expressed by the number of teeth per inch (25.4mm) in the British system.

　　

　　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.Now, everyone is right Plating filter Are more concerned, hoping to get more benefits from it. 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.

　　The controller is the core component of the electric wheelchair, which can also be understood as the “steering wheel” to control the direction of the wheelchair, and is responsible for the operation of the linkage motor. Its quality directly determines the maneuverability and service life of the electric wheelchair, and the functions and performance of the controller equipped with different configurations of electric wheelchairs will be different. Advanced electric wheelchairs are usually equipped with intelligent control system, which can freely adjust the speed and direction according to the user’s habits and environment to provide a more comfortable driving experience (controllers can be divided into basic models/with folding function/with reclining function/multi-function buttons according to the operation panel) and other feedback functions of intelligent voice broadcast. However, the basic electric wheelchair usually has simple control function, and it is not equipped with the common functions of intelligent voice broadcast and mobile phone remote control adaptation. Individual manufacturers have also added usb-adapted mobile phone charging port and lighting lamp to the controller.Therefore, we should understand 電動輪椅 Many benefits, absorb and summarize, and use them. https://www.hohomedical.com/collections/light-weight-wheelchair

　　

　　Most imported brand controllers are composed of upper and lower controllers, while most domestic brands only have upper controllers. Generally, the brushless ones in China are generally divided into upper controller and lower controller, and most of the brushes have only upper controller. Among the imported controller brands, PG in Britain and Dynamic in New Zealand are widely used. Domestic brands include Wuyang and Shiyou, Shanghai Zhilian Aomang, Nuole, Maikong, Pilotage, etc. Comparatively speaking, imported brands are better, and the cost and price are higher than domestic brands. However, in recent years, the rise of domestic products can also meet the needs and experiences of most consumers. You can also use the following operations to judge whether the controller is good or bad.

　　

　　1. Turn on the power switch and push the controller to feel whether the vehicle is stable when starting; Release the controller and feel whether the car stops immediately after a sudden stop. It is advisable to judge whether the controller is normal by starting and stopping slightly.

　　

　　2. Control the rotating car to rotate 360 degrees in situ, and feel whether the steering is smooth and flexible, subject to the steering sensitivity.

　　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 other words Fastener It is possible to develop in a good direction, and there are still many places worth looking forward to in the future. 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 chemical formula for nitric acid is HNO3. Anhydrous pure nitric acid is a colorless liquid that easily decomposes into nitrogen dioxide, resulting in a reddish brown color.So we can draw a preliminary conclusion, Plating filter It is helpful to the needs of the industry market and social development. http://www.luoyuan108.com/

　　

　　Many chemical users need to choose nitric acid pumps. So, how should nitric acid pumps be selected and which pump is better? Firstly, when transporting nitric acid, it is necessary to understand the characteristics, temperature, concentration, density, and equipment conditions of nitric acid, and then choose the corresponding pump type. Usually, nitric acid pumps can use 304 or 316L, but nitric acid reacts with metals. For the sake of service life, it is recommended to use fluoroplastic magnetic pumps. Of course, fluoroplastic centrifugal pumps can also be used. Generally, we recommend choosing magnetic pumps, which are fully enclosed, without shaft seals, and have the advantage of no leakage.

　　

　　It should be noted that nitric acid has swelling properties for most rubber and fluororubber. Therefore, it is recommended to use expanded PTFE or pure PTFE for the auxiliary static seal of the pump (due to the hardness of pure PTFE, the sealing surface of nitric acid pumps often cannot be tightly compressed, so it is recommended to use soft PTFE).

　　Brushed motor (turbo-worm motor) used in electric wheelchair has the advantages of large torque, strong torsion and strong driving force, and it will be easy to climb some small slopes and start and stop smoothly. Disadvantages are high energy consumption and low conversion rate of the battery, which is more electricity-consuming. Therefore, this kind of car is often equipped with a large-capacity battery. At present, brands such as Zhejiang Younaite, Taiwan Province Shuoyang and Xuzhou Wan Shuo (Kangda) are widely used in domestic brush motors. Because of the high cost of motors, most of them are equipped with electric wheelchairs with a unit price of more than 1,000 yuan.know 電動輪椅價錢 Our growth has to go through many hardships, but entrepreneurs are never afraid and boldly move forward. https://www.hohomedical.com/collections/light-weight-wheelchair

　　

　　Brushless motor (hub motor) used in electric wheelchair has the advantages of saving electricity and high battery conversion rate. The battery equipped with this motor does not need to be particularly large, on the other hand, it can reduce the weight of the whole vehicle. Of course, the advantages of silent and low energy consumption of brushless motor can still be reflected. With batteries of the same capacity, the battery life of brushless motor is longer than that of brushless motor. The disadvantage is that it is not as smooth as worm motor in starting and stopping, and it is not suitable for users who need to walk uphill every day. In recent years, it is more common on urban roads. There are other brands such as domestic Jindun, Uninet and Shilin. Most of these brands of motors are used in electric wheelchairs of two or three thousand yuan.

　　

　　Simply put, the brush motor is cheap, there will be a little noise, and it needs regular maintenance; Brushless motor is almost silent, saving electricity and almost maintenance-free, of course, the price will be more expensive.

　　

　　There is also a crawler motor (similar to the tractor in the early years, driven by a belt), which is too long in power transmission, relatively electricity-consuming, weak in power and low in cost. At present, only a few manufacturers are applying this motor.

　　

　　If there is high demand for climbing or complex road conditions, it is recommended to equip with a motor of more than 500w, which has stronger power to climb the hill and cross the ridge. Please choose according to your own situation.

　　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.from Mining support system From the reference value, it can also bring a lot of inspiration to other industries. 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.