In chip-level repair of mobile devices, steel mesh is a crucial component. A high-precision, scientifically designed, and properly selected steel mesh can significantly improve repair efficiency and success rate. Phonefix will systematically introduce the steel mesh product system, code meaning, purchase recommendations, and answer common usage questions, aiming to provide you with a clear reference guide.
I. Steel Mesh Overview
Steel Mesh is a high-precision stainless steel mold used to define the application area and solder paste dosage on PCB or chip pads in devices like mobile phones. Precise solder ball placement with steel mesh ensures stable chip soldering to the motherboard.
Steel Mesh Categories
The UBGA series, Regular series, and UBGA mini series are categorized based on repair scenarios and compatibility. Key concepts include:
1. Comprehensive Mesh: A steel mesh composed of a CPU and various chips.
2. CPU Collective Mesh: A steel mesh containing multiple CPUs (no other chips).
II. Product Series Overview
Steel mesh products are mainly divided into three series, each with a clear positioning to meet the different scenario needs of repair technicians.
1. UBGA Series:
This is the newly launched series, characterized by high integration and no repetition. It is classified by chip brand, including Comprehensive Mesh and CPU Collective Mesh, and provides a variety of combined sets. The series is further divided into two types.
2. CPU Collective Mesh:
Developed for each CPU brand; one mesh integrates 8 main CPU models.
· Usually equipped with a dedicated matching soldering ball planting platform.
· Supports both manual solder ball planting and use with the solder ball planting platform, suitable for batch CPU re-planting repair scenarios.
3. Regular Series
Long-standing core product, with two classification methods: by chip brand and by mobile phone brand.Includes Comprehensive Mesh and CPU Collective Mesh.
Key advantages: fast update speed, complete model library.
Supplementary role: The Regular series supports models not covered by the UBGA series, especially niche or newer ones. For older or less common chips, a BGA Reballing Station is essential for precise solder balling and reliable chip reinstallation.
4. UBGA mini Series
Small steel mesh with two Solder Balls planting positions, usually an integrated CPU mesh.
Design features: compact size, strong portability.
Usage: Can be used with the corresponding UBGA mini solder ball planting station.
Suitable scenarios: Repair technicians with limited desktop space or those who need to work on-site.
III. Product Code Rules
Each series' code contains clear information. Understanding the rules helps to quickly and accurately select the required product.
UBGA Series Code
Classified by CPU chip brand:
Apple: UIP, APU
Qualcomm: QSD, QSU
MediaTek MTK: MTK, MTU
HiSilicon: HIS, HIU
Samsung: SMG, SMU
Comprehensive Mesh: Denoted by MIXU
Key identification: Codes with "U" indicate CPU Collective Mesh; codes without "U" indicate Comprehensive Mesh.
IV. Common Questions
Here are some common questions and answers about steel mesh and soldering balls you might need to know.
1. What is an Isolation Mesh?
Isolation Mesh is a specially designed steel mesh, mainly used to solve two problems:
· Some CPUs may short-circuit after solder balling due to deformation. The Isolation Mesh prevents this by isolating prone ground pads.
· Isolates the pads of specific circuits to prevent circuit short circuits.
2. Why does the steel mesh bulge when heated?
This is a common problem caused by uneven heating.
Solutions:
· Place a tissue on the solder ball station, then position the chip and steel mesh. Press the center of the mesh with tweezers to create a slight concave for solder balling.
· Use the tissue to prop up the four sides of the steel mesh; when heating with a YCS Hot Air Gun, the four sides bounce up due to thermal expansion, offsetting the bulge in the middle.
· Use magnetic ball planting station, Uniformly fixes the steel mesh via magnetic force, fundamentally preventing bulging and simplifying the planting process.
3. Why does solder bridging occur during planting?
Solder bridging primarily occurs because the solder paste is too wet, or because the steel mesh moves during solder scraping.
Solutions:
Use a tissue to absorb excess flux on the surface of the solder paste or when scraping solder, fix the steel mesh firmly with hands or tools to ensure no movement during the scraping process.
Conclusion
Choosing the right steel mesh and mastering correct usage skills are the keys to improving repair quality and efficiency. It is hoped that this guide can help you better understand the product system and make the most suitable choice according to your business needs. If you want to gain more knowledge about repair tools or purchase professional mobile phone repair tools, please feel free to contact China Phonefix.
