After investigation, we found that the main quality problem of flat plate solar collectors is leakage, and it was usually found at the welded joints between the header and riser.
Let’s see how we solve this problem?
1. Special Welding Rod:
Most suppliers use Cu-P filler metal during the grid welding. SolAqua selects a 5% silver-contained copper welding rod which has better fluidity and flexibility to avoid the breaks or cracks caused by expansion and contraction.
2. Vertical Welding:
Almost all suppliers use horizontal welding, this is because it’s easier and more efficient during operation. But the horizontal welding has a problem, the welding fluid can’t penetrate evenly into the interior of the header. SolAqua uses vertical welding to make sure the welding material penetrates deeply into the copper tube and ensures the reliable sealing inside and outside of the header tube. Below is a photo for your reference. Sample B is from SolAqua, Sample A is from other suppliers.