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Working principle of slow wire processing

 Slow wire walking, also called low-speed wire walking, is a kind of CNC machining machine tool that uses continuously moving fine metal wire as an electrode to pulse spark discharge on the workpiece to generate a high temperature of over 6000 degrees, ablate metal and cut into a workpiece. The principle of wire processing is the phenomenon that there is a gap between the wire electrode and the workpiece, and the metal is removed by continuous discharge. Since the slow-moving wire cutting machine adopts the method of wire electrode continuous feeding, that is, the wire electrode is processed during the movement, so even if the wire electrode is worn out, it can be continuously supplemented, so it can improve the machining accuracy of the parts and slow the wire. The surface roughness of the workpiece processed by the cutting machine can usually reach Ra=0.8μm and above, and the roundness error, linear error and dimensional error of the slow-moving wire cutting machine are much better t

Hydrostatic guideway of CNC machining lathe

The static pressure slide rail (TTW guide) of the CNC machining lathe transfers the oil with a certain pressure through the throttle to the oil cavity between the sliding surfaces of the slide rail (TTW guide) to form a pressure oil film to float the moving parts , Make the sliding rail (TTW guide) surface in a pure liquid friction state.   CNC machining General CNC machining usually refers to computer digital control precision machining, CNC machining lathe, CNC machining milling machine, CNC machining c17200   beryllium   copper   and milling machine, etc. The feed route of finishing is basically carried out along the part contour sequence. Therefore, the focus of determining the feed route is to determine the feed route of rough machining and idle stroke. In the numerical control processing, the control system issues instructions to make the tool perform various motions that meet the requirements, and the shape and size of the workpiece are expressed in the form of numbers and lette

Introduction of KOVAR parts

KOVAR parts are commonly used as metal casing materials in the electronic packaging industry. Because they have a linear expansion coefficient close to that of molybdenum group glass, and can produce less sealing stress during the sealing (melting) process with molybdenum group glass, so To obtain good air-tightness, in order to make the metal tube and shell to achieve air-tight sealing, in the entire sealing process, the annealing process undoubtedly plays an important role as a link between the previous and the next. The internal stress generated during KOVAR  machining also prepares the material structure for the implementation of the subsequent process-the sealing process of the metal parts. The main purpose of annealing Kovar shell before sealing is to: (1) Eliminate machining stress. When Kovar undergoes plastic machining deformation during cold working, about 10% to 15% of the applied energy is converted into internal energy, which is commonly referred to as internal stress,

Urea for vehicles is a heavy-duty diesel vehicle that meets the National IV emission standards

<p style=”margin: 0px; font-family: Times New Roman; line-height: 22px; white-space: normal;”><span style=”margin: 0px; font-size: 14pt;”>Urea for vehicles is A must-have product for heavy-duty diesel vehicles to meet the National IV emission standards. Urea for vehicles refers to an aqueous urea solution with a urea concentration of 32.5% and ultrapure water as the solvent. The raw materials are urea crystals and ultrapure water. For heavy-duty trucks, buses and other diesel vehicles to meet the National IV emission standards, a suitable SCR system must be selected for exhaust gas treatment, and this system must use urea solution to treat the nitrogen oxides in the exhaust gas. Therefore, vehicle urea solution has become an essential product for heavy-duty trucks and buses to meet the National IV emission standards. <br style=”margin: 0px;” />&nbsp;&nbsp;&nbsp;&nbsp; SCR is the best choice for reducing emissions in China. At present, the current domestic diesel national standard GB19147-2009 requires a sulfur content of ≤350ppm, while the ECR-DOC technology requires a sulfur content of oil products below 10ppm, so there is no promotion condition in China for the time being. SCR can withstand 350ppm of sulfur-containing oil, so it has a technical basis for promotion. Because the fuel economy of the National IV engine using SCR technology is better than EGR technology, the engine changes are small, the fuel and oil requirements are lower, the technology upgrade continuity has advantages, the SCR catalyst has good durability and there is no catalyst blockage Therefore, SCR technology is the most suitable technology route for the emission reduction of heavy diesel vehicles in China's national conditions. <br style=”margin: 0px;” />&nbsp;&nbsp; Urea for vehicles is an aqueous urea solution with a concentration of 32.5% and a solvent of ultrapure water. The raw materials for production are urea crystals and ultrapure water. The key point is the purity of the raw materials . From the perspective of the production process, although the purity requirements for the raw material of urea for vehicles are higher than the requirements for general industrial use, the current domestic process can already meet the actual application needs. The production process of automotive urea is not sufficient to build a high barrier to entry. <br style=”margin: 0px;” />  The domestic vehicle urea is mainly purified from industrial urea. The main principles are: 1) When the temperature is 70-75℃, the urea is hydrolyzed in the aqueous solution. 2) When the temperature is below 30°C, urea will crystallize from the aqueous solution again. 3) Each time of hydrolysis and crystallization, its purity will be greatly improved. Generally, once industrial grade urea is used for hydrolysis and crystallization, it can meet the requirements of automotive urea standards, and the output ratio is 1.5:1. <br style=”margin: 0px;” />  Urea for vehicles must use first-class ultrapure water in the electronics industry. Because the SCR catalyst carrier is prone to metal ion poisoning and loses its catalytic effect, the automotive urea solution must use first-grade ultrapure water in the electronics industry (resistivity ≥18MΩ?cm). The car urea solution will start to freeze at -11°C, and it will freeze completely at -20°C in actual use. The current technology is to reduce the freezing point of the solution by adding a modifier, and adding a heating device to prevent the solution from freezing. </span></p><p style=”margin: 0px; font-family: Times New Roman; line-height: 22px; white-space: normal;”><span style=”margin: 0px; font-size: 14pt;”>Urea solution for vehicles (AdBlue) is a solution prepared with high-purity urea without any other additives and pure water. The urea content in the solution is 32.5% (mass fraction). Most domestic and foreign heavy-duty diesel engine manufacturers have adopted SCR (Selective Catalytic Reduction) technology to meet the requirements of Euro IV and Euro V motor vehicle emission standards. Vehicles that choose SCR technology must add urea solution as a catalytic reducing agent to make the vehicle meet the emission standards. <br style=”margin: 0px;” />&nbsp; &nbsp; &nbsp; Diesel engine exhaust gas treatment fluid (commonly known as: automobile urea, automobile urea, automobile environmental protection urea), called AdBlue in China and Europe, and called in America It is DEF and is called ARLA32 in Brazil. AdBlue is a high-purity transparent liquid composed of 32.5% high-purity urea and 67.5% deionized water, with a slight ammonia smell. If it splashes, the water evaporates and crystals form. AdBlue is used in cars, trucks, buses and heavy-duty non-road use diesel engine vehicles equipped with SCR (vehicle selective catalytic reduction exhaust gas aftertreatment) system. It is a consumable that must be used in SCR technology. The harmful nitrogen oxides emitted by diesel engines are converted into harmless water vapor and nitrogen. The main components of the SCR system include catalyst, AdBlue injection device, AdBlue container and AdBlue dose controller. Almost all heavy-duty vehicle manufacturers in Europe, the United States, and Asia, including China, also equip their vehicles with selective catalytic reduction systems and AdBlue working fluids to meet the new nitrogen oxide emission standards (such as Euro 4, Euro 5) AdBlue and Under the combined effect of SCR technology, it can optimize engine performance and fuel consumption, reduce diesel consumption by up to 6%, and significantly reduce costs. The average consumption of AdBlue is 5% of general diesel consumption, which is about 1.5 liters per 100 kilometers of highway driving. AdBlue can only be used to configure the engine combination of the SCR system, because it is neither a fuel nor a fuel additive. AdBlue implements standards in compliance with ISO22241, DIN70070 and CEFIC regulations to ensure the effective operation of the SCR system. AdBlue is not harmful to the environment and is classified as a transportable liquid with the lowest risk. <br style=”margin: 0px;” /><br style=”margin: 0px;” />   At present, domestic automotive urea production is dominated by small and medium-sized private enterprises, and channel sales capabilities are lacking. The domestic automotive urea is mainly produced by enterprises such as Jiangsu Klanso, Liaoning Rundi, Jingmai Chemical, and Beijing Yili. The production capacity of each company is between 100,000 to 300,000 tons per year. Among them, Jiangsu Klanzol and Liaoning Rundi have an annual production capacity of 300,000 tons, and have a series of modifier patents for the problem of low-temperature solidification of urea for vehicles. Jiangsu Klanzo has exported the urea solution for Klanzo vehicles to Russia, Eastern Europe and South America. But for the current small private enterprises, the inability to master the core sales channels is the fundamental weakness of their development. <br style=”margin: 0px;” />&nbsp;Guangdong Chuanghongyu urea energy-saving products came into being. For details, please contact 136 8021 1314&nbsp;</span></p>&lt;div class=”content” style=” margin: 0px;”>&lt;/div>

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