Analysis of common problems in SMT patch In the SMT chip processing factory, we often talk about some common problems, such as short-circuiting of chip components, solder balls on solder pads, and solder joints. We find some of the common reasons for these common problems in SMT placement processing from the following common reasons. If you find something wrong or supplemented, please ask.

- Sep 27, 2019-

Analysis of common problems in SMT patch

In the SMT chip processing factory, we often talk about some common problems, such as short-circuiting of chip components, solder balls on solder pads, and solder joints. We find some of the common reasons for these common problems in SMT placement processing from the following common reasons. If you find something wrong or supplemented, please ask.

First, the cause and solution of the short circuit

Cause of the solution

Pad design is too wide / too long Modify PCB Layout

No solder mask between pads

Pad gap is too small

Second, the reasons and solutions for tin beads

Cause of the solution

Solder mask printing is not good PCB incoming control

Moisture or dirt on the pad to remove moisture or dirt from the PCB

Third, the cause and solution of the virtual welding

Cause of the solution

The pressure of the printing paste is too large to reduce the pressure of the printing blade

Tin powder oxidation, flux deterioration Replace solder paste

The preheating zone is heating up too quickly. Adjusting the furnace temperature curve

Track speed is too fast, reducing reflow soldering speed

The above is the industry consultation provided by smt patch processing factory Shenzhen Pengzexiang Technology Co., Ltd., I hope to help you! Please contact us if necessary: http://www.oem-pcb.com pcb@sunsoartech.com

 


Previous:What are the causes of PCBA patch processing? PCBA processing manufacturers PCBA chip processing and production process, due to the impact of operational errors, it is easy to cause PCBA patch defects, such as air welding, short circuit, erection, missing parts, tin beads, lame, floating height, wrong parts, cold welding, Reverse, anti-white reversal, offset printing, component damage, tin less, poly tin, gold finger tin, overflow glue, etc., need to analyze these defects, improve, improve product quality. Analysis of Causes of PCBA Chip Processing Defects First, air welding Next:The basic process composition and process flow of SMT The basic process composition of SMT includes: silk screen (or dispensing), placement (curing), reflow soldering, cleaning, inspection, rework silk screen: its function is to print solder paste or patch glue on the pad of PCB, which is yuan Prepare the soldering of the device. The equipment used is a screen printing machine (screen printer), located at the forefront of the SMT production line. Dispensing: It is a fixed position where the glue is dri