1.1 Apply flux to the solder pad before soldering, and use a soldering iron to prevent the solder pad from being tinned or oxidized, resulting in poor soldering. The chip generally does not need to be processed.1.2 Carefully place the QFP chip on the PCB with tweezers, taking care not to damage the pins. Align it with the pad to ensure that the chip is placed in the correct orientation. Adjust the temperature of the soldering iron to more than 300 degrees Celsius, apply a small amount of solder to the tip of the soldering iron, use the tool to press down on the chip in the aligned position, an...
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Grip of the soldering iron: There are three types:1) The anti-grip method is to hold the handle of the soldering iron in the palm with five fingers. This method is applicable to high-power soldering irons, and is connected to the welded parts with large heat dissipation.2) Positive grip method, the electric soldering iron used in this method is also relatively large, and most of them are curved soldering iron tips.3) Holding the pen method, this method is suitable for low-power electric soldering iron, welding parts with low heat dissipation, such as welding radio, printed circuit board of TV ...
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2018
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Mobile phone repair soldering station lead-free soldering iron head maintenance and maintenance1. Soldering 63% to 37% lead should be used when soldering the appropriate tin wire, and the soldering iron tip is often protected with a tin layer. In addition, we should try to use thicker tin wire for welding work, because the thicker tin wire butt welding head has more...1. Use the appropriate tin wireSolder should be used with 63% to 37% lead in soldering and often with a tin layer to protect the soldering iron tip. In addition, the thicker tin wire should be used as much as possible for the wel...
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2018
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From April 12th to 15th, the 15th China International Electronic Production Equipment and Microelectronics Industry Exhibition (NEPCON2005) was held in Shanghai as scheduled. With the participation of 700 exhibitors from 21 countries and regions, this exhibition became China. The most influential event in electronics manufacturing.From the perspective of exhibitors and seminars, lead-free, SMT placement machines and soldering have become the three hot spots of this exhibition. Among them, lead-free throughout the entire exhibition, from the basic solder to the lead-free upgrade of electronic e...
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2018
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Lead-free solder contains no lead and has a higher melting point than conventional (63% tin + 37% lead) solder.Common lead-free solder:· Sn-Ag (tin + silver, 96-98% tin)· Sn-Cu (tin + copper, 96% tin)· Sn-Ag-Cu (tin + silver + copper, 93-96% tin)· Sn-Ag-Bi (tin + silver + tantalum, 90.5-94% tin)· Sn-Ag-Bi-Cu (tin + silver + 铋 + copper, 90-94% tin)The 63/37 lead solder bath has a melting point of 183 ° C and the freezing point is also 183 ° C. Note: This solder does not appear colloidal [the same temperature point from liquid cooling to solid (or vice versa)]....
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2018
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A, anti-static routine process requirements:1. The operator must wear a wired anti-static wrist;2. The table top involved in the operation of electrostatic sensitive devices shall be equipped with an anti-static mat;3. ESD sensitive devices must be transported by electrostatic shielding and anti-static devices;4. When preparing to open the seal and test the static sensitive device, it must be carried out on the anti-static workbench. Conditional ion air generator can be used to remove the charge in the air;5. The welding equipment and forming tooling equipment used for assembly must be grounde...
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2018
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1. The human body type means that the friction between the body and the clothes generates a triboelectric charge when the human body moves. When people hold ESD-sensitive devices without first placing charge on the ground, the triboelectric charge will move to the ESD-sensitive device and cause damage.2. The charged type of microelectronics refers to both ESD-sensitive devices, especially for plastic parts. When automated production, triboelectric charges are generated, and these triboelectric charges are quickly discharged through a low-resistance line to a highly conductive, solid ground. Th...
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2018
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1 General specification for anti-static raised floor SJ/T 10796-20012 General specification for anti-static veneer SJ/T 11236-20013 Test methods for electrostatic properties of floor coverings and assembled floors SJ/T 11159-984 Test methods for antistatic systems for electronic products manufacturing SJ/T 10694-965 General rules for electrostatic protection of communication equipment YD/T 754-19956 Communication room static protection general YD/T 754-957 Anti-static technical requirements for the manufacture of electronic components SJ/T 10630-958 Safety standard for fireproof performance of...
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2018
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SAIER MRO is committed to providing high quality imported industrial products. The products currently in operation cover: eight categories of welding equipment, pneumatic and hydraulic components, industrial control systems, instrumentation, electrical and electrical, ventilation and heat transfer, hardware tools, security and labor insurance, more than 20 categories. There are thousands of kinds of goods, such as chemical, electric power, metallurgy, automobile, coal, paper, food, ship, manufacturing and so on. We have been continuously improving our supply channels, optimizing our storage an...
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2018
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MRO Procurement (Maintenance, Repair and Operations )First, what is MRO procurementMRO is an abbreviation for English Maintenance, Repair and Operations, which refers to maintenance, repair and operation. MRO procurement refers to a business operation in which an enterprise obtains industrial products or services from the supply market under certain conditions as a corporate resource to ensure the normal production and operation activities of the enterprise.Second, the advantages and disadvantages of MRO procurement(1) Advantages1. Since all procurement processes use e-commerce, it effectively...
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2018
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浏览次数：6