Surface mount technology mainly includes two parts: core technology and auxiliary process. The core process consists of three parts: printing, patch and re-flow, which is very important for any types of products production.The auxiliary process mainly consists of "glue" technology and optical auxiliary automatic detection technology, which is not necessary, according to the characteristics of products and customer demand to determine weather need or not.
Basic Process Constitument elements of SMT
silk screen-->(dispensing)-->mounting-->(cure)-->re-flow soldering-->cleaning -->testing-->repairing
Silk Screen: taking the solder paste or glue stencil to patch PCB and preparing for the electronics parts welding by using the equipment of Silk Screen Machine(screen printing machine),located in the forefront of the SMT production line.
Dispensing: dropping the glue to the fixed position of PCB, its main role is to fix the components on the PCB board by using the equipment of dispensing machine, located in the forefront of SMT production line or behind the test equipment.
Mounting: installing the surface assembly parts to the fixed position of PCB by the equipment of Mounter, located in the back of screen printing machine in SMT production line .
Curing: Melting the heraeus so as to make the surface assembly parts and PCB board firmly bonded together by using the equipment of curing furnace, located in the back of the Mounter in the SMT production line
Re-flow soldering: Melting the soldering paste so as to make the surface assembly parts and PCB board firmly bonded together by using the equipment of re-flow oven, located in the back of the Patch machine in the SMT production line
Cleaning:removing the harmful residues on the assembled PCB, such as welding flux by using the equipment of washing machine, its location is not fixed,no matter on production line or not.
Testing: Testing welding quality and quality of the PCB assembly by using the equipment of magnifying glass, microscope, online tester (ICT), flying needle tester, automatic optical inspection(AOI), X-RAY detection system, function tester and so on, its location is depending on the needs of the test and it can be located in the right place.
Repairing: reworking failure PCB by using soldering and repair workstation. It can be located at any position in the production line, the role of PCB in failure to detect rework tools used for soldering, repair workstation. Configuration at any position in the production line.
The original link: http://www.nod-pcba.com/news/452-en.html
没有评论:
发表评论