SMT reflow oven is one of the key processes in SMT processing, and the quality of surface assembly is directly reflected in the reflow oven results. But the soldering oven quality problems in the soldering is not entirely reflow process, because the reflow quality in addition to the temperature profile has a direct relationship with the temperature profile, but also with the SMD processing plant SMT production line equipment conditions, PCB pads of the producibility of the design, component weldability, solder paste quality, the quality of the PCB processing and the processing quality of the SMT processing of each process parameters, and even with the operation of the SMD processing plant operators have a close relationship. Operation are closely related. So, what factors will cause quality problems on the SMT reflow oven?
I. The impact of components
When the component welding end or pin is oxidized or contaminated, reflow oven soldering will produce poor wetting, soldering, hollow and other welding defects. Component coplanarity is not good, will also lead to welding defects such as soldering.
II. The impact of PCB
SMT mounting quality and PCB pad design has a direct and very important relationship. If the PCB pad design is correct, mounting a small amount of re-skew can be reflowed, due to the role of the surface tension of the molten solder and be corrected; on the contrary, if the PCB pad design is not correct, even if the mounting position is very accurate, reflow soldering, but there will be component position offset, monument and other soldering defects; SMT SMD quality and PCB pad quality also has a certain relationship, PCB pad oxidation or Pollution, PCB pad moisture and other cases, reflow soldering will produce poor wetting, virtual solder, solder balls, voids and other welding defects.
III. The impact of solder paste
Solder paste in the metal powder content, metal powder oxygen content, viscosity, thixotropy, printability have certain requirements. If the solder paste metal powder content is high, reflux temperature metal powder with the evaporation of solvent and flyover, if the metal powder oxygen content is high, but also exacerbate the spattering, the formation of solder ball, but also cause defects such as non-wetting. In addition, if the salinity of the solder paste is too low or the thixotropy of the solder paste is not good, after printing the solder paste graphic will be Juan trapping, and even caused by the wither, reflow oven soldering will form a solder ball bridging and other welding defects. If the printability of the solder paste is not good, the printing of the solder paste is just sliding on the template, in this case it is not printed at all solder paste.
Introduction of NeoDen IN8C reflow equipment
NeoDen IN8C reflow oven is a new environmentally friendly, stable performance intelligent automatic orbital reflow soldering.
This reflow solder adopts the exclusive patented design of “even temperature heating plate” design, with excellent soldering performance.
with 8 temperature zones compact design, lightweight and compact. to achieve intelligent temperature control, with high-sensitivity temperature sensor, with stable temperature in the furnace, the characteristics of small horizontal temperature difference. While using Japan NSK hot air motor bearings and Switzerland imported Heating wire, durable and stable performance.
Post time: Nov-15-2024