, wave soldering, electronic products testing, assembly, SMT (
, wave soldering, electronic products testing, assembly, and other products professional production and processing of the company.
Artificial measurement method of PCB is: will the three PCB Angle close to the desktop, and then measuring the distance the fourth Angle is apart from desktop.
This method can only roughly estimate measurement, more effective methods and application of moire image technology, etc.
Moire image method is: on the tested PCB placed an inch 100 line grating, setting up a standard light source at the top to 45 ℃ incidence Angle beam through grating on the PCB, raster image generated by the grating on the PCB, and then use a CCD camera above the PCB is to observe the raster image.
At this moment, on the whole PCB can see two grating geometry between the interference fringes, the stripe shows the Z direction of the offset, count the number of the stripe calculated height of PCB's offset, and then into warp degrees by calculation.
2, 3 PCB solderability test, wipe clean may also cause pollution of the template at the bottom of the tin ball, more residues to the PCB surface, forming a similar tin the splash phenomenon.
If there is no effect improvement measures, this may be the reason.
Second, the improvement Suggestions splash content can be lengthened by increasing preheat temperature or preheat time be improved or in addition to, the reasons are as follows: (1) absorption of moisture is to take off the dry: (2) preheating has more oxide, thus slowing down the condensing process: (3) due to the loss of volatile components, flux for greater viscosity, make its reaction rate slower with solder oxide: company production base covers an area of more than 2000 square meters, owns more than 100 employees.
Has a group engaged in years of experience in management, biotech, quality management personnel.
Have SMT single/double, the soft board and so on various process of production, quality control ability.
At the same time with 1.
2 meters lamp plate production capacity.
At present, the company has a new travel three SMT production lines, including the high precision automatic printing machine DX, Hanwha high-precision high-speed placement machine SM471PLUS, high-precision placement machine SM481PLUS at a moderate speed.
8 zones reflow lead-free, imported equipment AOI optical detector, etc.
Large components design of large components, such as transformer, diameter of 15.
0 mm above the electrolytic capacitor, large current socket, etc. , can increase bonding pad by tin area to increase.
The shadow part of the figure 1 is to increase the solder area, requiring more area is at least equal with the solder area.
Large conductive area design in single and double panel and laminated outer conductive area, should be partial to open the window, and good layout on the cell surface;
If big conductive area have weld, the welding point should be on the basis of maintain its conductor continuity to isolate etch area.
To prevent the welding thermal stress concentration.
Welding plate isolation design is shown in figure 2.
At present, the PCB manufacturers use a large variety of solder paste, and there is no unified standard of classification, technical classification only now.
General activity according to the solder alloy melting temperature, flux and solder paste viscosity are classified.
(4) when the equipment after launch, saturated vapor area should have enough time to form, and inspection, convinced that the cooling coil to the cooling temperature specified in the operating manual, and then began to cleaning operations.
5. According to the usage, periodically with fresh solvent in solvent replacement boiling slot.
Continuous solvent cleaning process.
Continuous washing process is suitable for mass production and assembly line, cleaning quality is stable, because the operation is fully automatic, so is not affected by man-made factors.
In addition, continuous cleaning process, can join tilted high-pressure injection and fan-shaped spray of mechanical decontamination method, especially suitable for surface cleaning circuit board assembly.
SMT production capacity of about 3 million points.
Have three hand instrumentation and wave soldering production lines, can meet the circuit board at the same time long and short plug welding requirements.
Advanced BGA welding, BGA rework station, can carry on the batch of BGA, QFP welding and repair.
Existing equipment configuration, can quickly change the product variety of management methods, make our company already have the ability to mass production and can meet the needs of the many varieties, small batch production.
At present, my company customers in: military industry, electric power, IT, communication, industrial control, automotive electronics, consumer electronics and other fields.
Design is not reasonable, and the technological process of improper handling may cause PCB warp and bear, its testing methods in the IPC -
There are provisions in standard TM650, etc.
Test principle for basic: will be exposed in the assembly process of representative test PCB thermal environment, thermal stress on the test.
Typical thermal stress test method is rotating immersion test and solder float test, in this kind of test method, dipping PCB must have time in the molten solder, then remove warp and distortion test of PCB warp artificial measurement method is: will the PCB three Angle close to the desktop, and then measuring the distance the fourth Angle is apart from desktop.
This method can only roughly estimate measurement, more effective method and moire photograph method, etc.
Moire image method is: on the tested PCB placed a piece of the light of 100 lines per inch, of setting up a standard light source in the above 45 'incident Angle through light shed to the PCB, the light have shed light on the PCB image, and then use a CCD camera in the PCB directly above (
To observe the light images.
At this time, can see two shed light on the whole PCB between a collection of interference fringes, the stripe shows the Z axis offset, count out the number of stripes calculated height of PCB's offset, and then into warp degrees by calculation.
How much money electronics assembly
Turn-key Electronics Manufacturing Services for Printed Circuit Boards and Assembly