Terminology of SMT chip proces
Terminology for quality and appearance inspection of SMT solder joints
1 stele: the phenomenon that one end of a component leaves the pad and is inclined upward or upright.
2. Soldering or short circuit: the solder joint between two or more solder joints that should not be connected, or the solder of solder joint is connected with adjacent wires.
3 displacement or offset: the component deviates from the predetermined position in the horizontal (horizontal), longitudinal (vertical) or rotation direction in the plane of the pad (based on the center line of the component and the center line of the pad).
Empty soldering: refers to the assembly phenomenon that the solderable end of the component is not connected with the pad.
5 reverse direction: it refers to the wrong direction when mounting polar components.
6 wrong parts: the model and specification of the components mounted at the specified position do not meet the requirements.
7. Less parts: materials are not attached to the position where components are required.
Exposed copper: the green oil on PCBA surface falls off or is damaged, resulting in the copper foil exposed.
Blistering: refers to the deformation of PCBA / PCB surface area expansion.
10 tin hole: there are blowholes and pinholes on the solder joint of components after passing through the furnace.
11 tin crack: tin surface crack.
12 hole plugging: solder paste remains in the plug-in hole / screw hole, resulting in hole diameter blockage.
Pin warping: refers to the up warping deformation of multi pin components.
14 side standing: refers to the direct welding of the side of the welding end of the component.
False welding / false welding: refers to the component welding is not firm, external or internal stress will appear poor contact, broken or connected.
16 anti paste / anti white: refers to the component surface silk screen is pasted on the other side of PCB board, and its product name and specification are not recognized.
17 cold welding / non melting tin: refers to that the surface of solder joint is not glossy and the crystal is not completely melted to achieve reliable welding effect.
Less tin: it refers to the low tin content of component pad.
More than 19 pieces: refers to the PCB does not require the location of components are pasted with components.
20 tin point: refers to tin point is not smooth, there are spikes or burrs.
21 tin bead: refers to the spherical tin spots or tin objects on PCBA.
22 open circuit: refers to the disconnection between components or PCBA lines.
Glue overflow: it refers to that the glue spreads out from under the component and is visible in the area to be welded, which affects the welding.
24 element floating height: refers to the phenomenon that the component body floats away from the PCB surface after welding.