Технология PCBA - анализ причин

During the production process of PCBA patch, due to the influence of operation error, пластырь PCBA легко, such as: empty soldering, короткое замыкание, standing upright, Недостающая часть, tin balls, подняться, floating height, неправильная часть, холодная сварка, reverse Direction, обратный белый/back, нейтрализовать, component damage, малое олово, more tin, консервы с золотыми пальцами, переполнение клея, etc. эти недостатки необходимо анализировать и совершенствовать для повышения качества продукции.

газовая сварка

The specificity of the red glue is weak; the mesh plate is not well opened; the copper-platinum spacing is too large or the copper is attached to small components; the scraper pressure is too large; the flatness of the components is not good (lifting feet, deformation) reflow furnace preheating zone heating up too fast ; PCB copper platinum is too dirty or oxidized;

The PCB board contains moisture; the machine placement is offset; the red glue printing is offset; the machine's plywood track is loose and the placement is offset; the MARK point is misilluminated and the component is biased, приводить к холостой сварке;

Второе короткое замыкание

The distance between the stencil and the PCB board is too large to cause the red glue printing to be too thick and short circuit; the component patch height is set too low to squeeze the red glue to cause a short circuit; Poor (too thick, отверстие для штифта слишком длинное, too large openings); red glue cannot bear the weight of the component; deformation of the screen or squeegee causes the printing of red glue to be too thick; the specificity of red glue is strong; empty dots The roll-up of the seal sticker paper causes the red glue printing of the peripheral components to be too thick; the reflow soldering vibration is too large or not level;

В - третьих, вставай

Разница в размерах по обе стороны меди и платины приводит к неравномерному натяжению; чрезмерно высокая скорость подогрева; отклонение машинных заплат; красное клейкое печатание толщина равномерная; неравномерное распределение температур в обратной печи; отклонение от печати в красном Клее; неподвижность направляющей станка приводит к сдвигу наклейки; нос шатается; красный клей слишком особенный; температура печи не соответствует требованиям; слишком большое расстояние между меди и платиной; маркер был ошибочно застрелен, и юаня тоже предвзято

недостающие элементы

Vacuum pump carbon sheet is not good enough vacuum leads to missing parts; suction nozzle clogged or poor suction nozzle; improper component thickness test or poor detector; improper setting of patch height; suction nozzle blowing too much or not blowing; suction nozzle vacuum setting improper (Applicable to MPA); The patching speed of special-shaped components is too fast; the head trachea is severely broken; the valve sealing ring is worn; there is a foreign body on the side of the reflow furnace track to wipe off the board components;

пять оловянных шариков

Insufficient preheating of reflow soldering and too fast heating; Red glue is refrigerated and the temperature is incomplete; Red glue absorbs moisture and causes splashing (indoor humidity is too heavy); Too much moisture in the PCB board; Add excessive thinner; Mesh plate opening design Improper; uneven tin powder particles.

нейтрализовать нейтрализовать

ориентировочный ориентир на платы не ясен; координатные ориентиры на платы не совпадают с ориентирами на экране; приспособление для крепления платы в печатной машине, and the positioning mold thimble is not in place; the optical positioning of the printing machine System failure; the solder paste omission of the printed screen hole does not conform to the design document of the circuit board. To improve the defects of PCBA patch, it is necessary to carry out strict checks in all aspects to prevent the problems of the previous process from flowing to the next process as little as possible.