SMT lines or SMT production lines refer to the assembly lines for PCB surface mounting and testing. Each process in SMT production has different flows and requirements, for which different processing machines and postitions cooperate to form a complete SMT line.
Compared with traditional technology, Surface mount techology has the characteristics of high density, high reliability, low cost, and smaller size, which reuires a more efficient processing SMT line.
According to the degree of automation, SMT production lines can be divided into automatic SMT lines and semi-automatic SMT lines. The main difference is whether the pick-n-place machine is fully automatic or semi-automatic, in which, semi-automatic requires manual printing or manual loading and unloading of PCB boards.
The main machines equipped in the SMT lines
1. Pick and Place Machine
The most important equipment in the SMT lines. The surface mount components are accurately placed on the PCB pads by moving the placement head of pick-n-place machine.
2. Solder Paste Mixer
The solder paste mixer can efficiently mix the solder powder and the solder paste evenly. Achieve more perfect printing and reflow effects, save labor and standardize this operation.
Used to bake PCB boards, remove moisture from PCB boards when necessary. It is usually the last link in the SMT lines.
4. SMT Loader
Automatically placed PCBs into the rack of solder printing machine.
5. Solder Paste Printing Machine
Used to print the solder paste to empty printed circuit boards. It is at the front of Pick-n-place machine in an SMT line.
6. SPI Machine (Solder Paste Inspection)
After solder paste printing, used for checking the thickness, area, and volume distribution of solder paste printed on the PCBs.
7. Reflow Machine
The reflow soldering is a process after pick-n-place process in the SMT lines, which is responsible for melting the solder bonded between circuit boards and components, then cold down to form the reliable electric connection. There are many types of reflow, such as hot air reflow, Infrared reflow, hot gas reflow, etc, in which, hot air reflow is generally used.
In SMT production lines, AOI machines are used before and after reflow soldering. It is able to detect the placement failure of components before soldering in pre-solder inspection also the soldering failure in post-solder inspection.
9. Docking Station
Used as a connection station between different equipment in an SMT line.
10. SMT Unloader
It is mainly used to receive and store pcb circuit boards after reflow soldering.
As a experienced PCB manufacturer, PS Electronics is employing fully automatic SMT production equipped with 5 high-performance SMT lines, which can meet the demands of medium to large voloume.