MOKOPCB - MOKO TECHNOLOGY LIMITED
Apr 21, 2020
In times of difficulty to obtain parts, increasing need for versatility and fast growth cycles, clean as well as affordable PCB remodel to conserve put together or bare printed circuit card are becoming increasingly essential. Every PCB or PCB setting up that can be fixed by rework safeguards our setting by not getting rid of it as well as by not having to generate new PCBs. Bauer Express PCBs have conserved more than 500,000 PCBs in recent times.
Using special, self-developed techniques, the specialists at MOKO Technology can, for instance, drill holes into formerly assembled assemblies. The precision represents the newly created published motherboard The work is only performed by workers with years of experience in PCB fabrication. State-of-the-art gauging technology allows ideal tracking of the job. Depending on the quantity as well as complexity of the rework, the shipment time is typically less than 5 working days after receipt of the goods. A specific service is also available for immediate PCB remodel, where it is feasible to execute remodeling within a few hours.
PCB Rework constructed boards.
Unsolder and after that solder in once again
In order to solve the unique problems to the fulfillment of consumers in the long-term, MOKO Innovation has actually purchased equipment. The focus right here was on straightforward and gentle material removal as well as re-soldering of parts. The choice fell on the Ersascope 1 and also the PCB rework system IR 550 A from Kurtz Ersa. At MOKO Technology, certain treatment was taken to make sure that the circuit board was warmed as homogeneously as possible. We keep the thermal anxiety on the boards as low as possible during the PCB remodel process. Consequently, we do not needlessly hinder the lifespan of the published circuit boards as well as parts. The fixing and refitting after that take place both manually and with mechanical support.
The IR 550 A rework system heats the PCB homogeneously using medium-wave infrared emitters (4 µm to 8 µm). Warming up the setting up is very important to prevent the PCBs from buckling and also to achieve a low-temperature slope ΔT from the top of the PCB to the bottom.
The leading heating in the Ersa systems is likewise created as a medium-wave infrared heating unit or hybrid heating system. The crossbreed heater is an infrared heating unit with a reduced level of convection. This way we can additionally attain a reduced straight temperature gradient, i.e. across the element, from edge to corner. Additionally, we prevent locations because of too much hot air as well as decrease the blowing away of bordering, unprotected elements.
Automated desoldering during PCB rework
In every process during PCB revamp, a sensing unit documents the temperature straight on the part. A closed control loophole controls and also manages the soldering procedure, which must minimize the danger of temperature level discrepancies and also the associated tension for the components and circuit board. Our staff members additionally work in a regulated manner when grabbing components from the circuit card. The IR 550 A from Kurtz Ersa is equipped with a vacuum pipette incorporated right into the leading radiator. This allows the desoldering process to be automated. The affixed vacuum cleaner suction mug automatically lifts the component off the board as quickly as the solder has thawed. This careful grabbing the component protects against any tension on the motherboard.
These mild procedures are especially in demand for package-on-package applications. When soldering in and out, the requirements for the homogeneity of the warm circulation are especially high. For instance, both degrees can be modified at the same time. Parts lying one above the other can be lifted off together after the solder melt. The same puts on the re-soldering of the parts. These can be put and soldered with each other, which streamlines the total procedure.
If different processing of the degrees is essential, this is likewise feasible. To do this, the temperature level profile have to be established very precisely, for instance, to desolder only at the top degree. In this case, also, the components on the top degree can be repositioned and also soldered in again. It is suggested to use the RPC 500 reflow procedure video camera to observe the solder thaw on both levels.
The Ersascope 1 vision system is recommended for examining the outcomes of all rework, but particularly when reworking BGAs (see lead picture). Along with one more X-ray analysis or various other data, the high quality of the solder joints can be examined aesthetically. Bridges, contamination or anomalies under the component can be recognized by doing this.
Unique jobs in PCB rework services
A high level of know-how and also contemporary tools are absolutely required for the expert handling of rework. When it comes to special jobs such as package-on-package or circuitry under BGAs, tact, experience and the right technical devices are essential. MOKO Technology has been doing PCBA as well as PCB manufacturing given that 2006, so we're currently very knowledgeable in managing the PCB rework. We validate that special tasks have actually additionally come near the Chinese professionals over the years. At first, the inquiries were workable, yet gradually we have developed a good track record for unique jobs to make sure that we are handling increasingly requiring jobs that have actually been and also will certainly be turned over. Our primary task is not just standard soldering as well as re-soldering of components. We frequently save the entire circuit board with our job, which suggests that our customers can satisfy their distribution days and also stay clear of unnecessary costs.
One of the supreme self-controls is the circuitry below a BGA. If the advancement of costly electronics has actually been inappropriate, these set up circuit card wind up with us. This means that links for BGAs were mostly neglected. As a result of the high packing density on the printed circuit card and the boosting miniaturization of the parts, we initially have to inspect every ask for technological feasibility. If it is possible to establish a wire bridge, the element has to be unsoldered. After that the printed circuit card and the solder pads must be without tin as well as the surface to be processed should be cleaned up of all disruptive variables. The cord jumpers are after that pulled by hand, calling for the greatest precision. It is particularly important to select the right cord size, otherwise short circuits might occur when touching the BGA balls. The components are then re-set as well as soldered. The soldering process must be very closely checked making use of camera tracking. This is followed by an X-ray analysis of the modified area.
According to the handling director from our business, keeping track of the soldering process during rework is a necessity. We usually perform a solder joint evaluation for these tasks in order to likewise define the soldering profile for the subsequent work. Camera monitoring is an important assistance. The initial analysis is made with the endoscope, complied with by more accurate results on the X-ray. This is the only way we can assure our customers premium PCB rework. In the package-on-package location, the experience obtained in reworking and the makers utilized for this are used. It does not matter whether rework is carried out or the client intends to have elements constructed using the package-on-package procedure. The jobs are really similar. In the package-on-package location, the BGA should additionally be precisely put and soldered. The soldering is likewise examined using a solder joint analysis to stay clear of mistakes as well as to develop an exact soldering profile for the consumer as well as the subsequent tasks.
The Ersa IR 550 A PCB rework system heats the circuit card homogeneously using medium-wave infrared emitters (4-- 8 µm). This stops regional overheating, supposed hot spots. Warming up the setting up is specifically essential to prevent deforming the PCB and to attain a reduced, upright Delta T, i.e. a temperature level difference on the top of the PCB from all-time low of the PCB. The top heating in our Ersa systems is likewise created as a medium-wave infrared heating unit or hybrid heater. The hybrid heater is an infrared heater with a low degree of convection. We can also attain a low, straight delta T across the part, from corner to corner. We additionally stay clear of locations as a result of too much hot air as well as we lower the blowing away of surrounding, unsecured components.
The temperature is tape-recorded in every process by a sensing unit directly on the part. The soldering process is regulated as well as controlled through a shut control loop, which lessens the danger of temperature level deviations and also the involved stress for the components and printed circuit card. Our group works equally as simple and also in a controlled fashion when getting elements from the circuit board. The Ersa IR 550 A is furnished with a vacuum pipette integrated into the top radiator, which allows the desoldering process to be automated. With the vacuum mug affixed, the element is automatically taken off the board as soon as the solder has actually melted. By thoroughly getting the part, we avoid any type of anxiety on the circuit card.
These mild procedures are particularly popular for package-on-package applications. The demands for the homogeneity of the warm circulation are particularly high below, particularly when soldering and desoldering. As an example, both levels can be modified at the same time. Components existing one over the various other can be lifted off together after the solder melt. The very same relates to re-soldering the parts. Joint positioning and joint soldering are possible and also simplify the total procedure, as the administration of MOKO Modern technology validated on demand.
If separate handling of the levels is required, this is likewise feasible. To do this, the temperature account should be set extremely specifically, e.g. simply desolder the top level. The subsequent positioning and re-soldering of the components on the upper degree are likewise possible. Making use of the reflow procedure cam (RPC) makes sense to observe the solder thaw on both levels.
The Ersascope 1 vision system is recommended for examining the results of all revamp, yet specifically when reworking BGAs. In conjunction with another X-ray analysis or various other data, the quality of the solder joints can be checked visually. Bridges, contamination or anomalies under the element can be identified.
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