PB-Free Soldering Services
|Bittele Electronics offers its global customers expertise in Pb-free soldering capabilities. It has a comprehensive list of Pb-free services that includes examining the effectiveness of Pb-free soldering with regards to solder alloy selection as well as evaluating the use of solder paste, wave solder flux and associated components and equipment. Bittele has established itself as an expert in this area and has involved itself in international standards organizations. Bittele Electronics is committed to a program of continuous improvement that includes process optimization, reliability, quality control, and cost reductions. Bittele offers its customers the following services:
Bittele Electronics prides itself by being in compliance with relevant PB-free and RoHS operational standards. We ensure that our PB-free services are compliant with standards through the implementation of specific processes. Bittele offers its expertise to customers who are seeking RoHS compliant printed circuit boards.
- Reworking PCBs
- Assembly (SMT or THA)
- Wave Soldering
- Materials Examination
Purchasing Pb-Free Parts
Bittele Electronics is capable of finding and purchasing Pb-free printed circuit boards, materials, and other parts as per a bill of materials. This is a service supports our turnkey Pb-free prototyping PCB assembly. For more information, contact the Bittele customer service department during normal working hours.
RoHS Assembly Capabilities
Bittele Electronics is capable of assembling RoHS PCBs that comply with the RoHS international standard In accordance with the standard, RoHS PCBs swill not utilize hazardous materials. Bittele's RoHS capabilities include PCBs, discrete components, or soldering connections. To should be noted that blank PCBs sealed with a lead-tin finish must be modified to be compliant with RoHS standards.
Requirements of Pb-Free Prototype PCBs
PB-free prototype PCBs are produced at temperatures of 30 to 50 degrees higher than leaded PCBs. This elevated temperature range means that PCB substrates and associated parts must be able to handle these higher reflow temperatures. In addition, to protect board-level chips, their moisture sensitivity specification should be approximately 2 classes greater than normally would be utilized. It should be noted that that Pb-free PCBs have a decreased shelf life when compared to leaded printed circuit boards.
Recommendations for Reflow Temperature Profiling
To ensure quality results, Bittele Electronics suggests having an extra PB-free PCB on hand as well as spare temperature sensitive components such as BGAs, heat slug components and more. These extra parts can be authentic components, non-functioning components, or dummy components that are cross-referenced substitutes. Most top-tier parts suppliers have non-functional, mechanical spares or other thermally compatible components.
PB-Free Solder Joints
Pb-free solder joints have a different visual appearance than leaded solder joints. This difference is due to the materials used to make Pb-free solder. Upon initial inspection, a PB-free joint looks like a "cold" solder joint. This is why it is important to have a trained specialist who knows what a Pb-free solder joint should look like. Bittele employs a trained staff that knows how to inspect Pb-free soldering as per the relevant IPC-610D standard and verify that the Pb-free solder joint meets all standards of quality.
PB-Free Bill of Materials (BOM)
It is the customer's responsibility to verify that the Pb-free BOM does not have any errors. The PCB and other parts must be in compliance with Pb-free requirements. For customers who need assistance, Bittele customer service can gladly help you. It should be noted that in situations where PCBs and associated parts come in moisture packaging that has been disqualified upon arrival at our production facilities, we require that these parts will need to be baked before proceeding with the assembly process.
Stenciling and Solder Paste Printing
The initial step of Pb-free PCB assembly is the application of the stencil to the PCB-free printed circuit board with Pb-free solder paste alloy (SAC305). This solder paste alloy is frequently utilized on SMT, Wave soldering and hand / wire soldering jobs. Upon completion of the soldering job, Bittele’s inspection staff will inspect the PCB to verify correct solder coverage and readiness for manufacturing.
Automated Assembly Processes
Bittele Electronics uses automated equipment to pick and place SMT components onto PCBs. The BOM is utilized in the placement process. Every component in the BOM has a designated part number. The automated pick-and-place machinery is programmed to pick up a specific part based on the part number and place it on the PCB. In this process, Pb-free compatible components must be specified. These parts must be able to withstand the elevated solder and processing temperatures of Pb-free PCB assembly.
Non-Automated Assembly Processes
Beyond automated assembly, Bittele Electronics will employ Through Hole and Hand /Wire soldering when necessary. These soldering processes are specified for areas when no leaded components need to be inserted. For manual soldering, Pb-free solder and soldering tools are utilized.
The Reflow Oven Process
Pb-free manufacturing concludes with processing the PCB through the reflow oven, which functions to melt the solder paste resulting in a metallic bonding between each board-level component and the PCB trace. As mentioned before, to be in compliance with RoHS standards, the PB-free parts and PCB must be processed at elevated oven temperatures. Compared to leaded processing, reflow processing has a much narrower temperature range or window. To control reflow processing and monitor thermal profiles, a reflow temperature profile is utilized. A reflow temperature profile includes the following factors: thickness, type of finish, PCB dimensions, and number of layers.
Once the reflow soldering process is completed, Bittele's technicians visually inspect the PCB to verify there are no manufacturing flaws. The inspection test is conducted in accordance to the IPC 610D soldering acceptability standard.
Pb-free PCBS that have successfully passed inspection are shipped separately in electrostatic discharge (ESD) packaging.