PU Sandwich Panel Moisture Corrosion Prevention Guide
📋 Step 1: Pre‑project selection assessment, match proper PU sandwich panel configuration For coastal and plum‑rain high‑humidity projects, do not directly adopt ordinary PU sandwich panel. First evaluate local salt‑spray level, ambient humidity, washing‑operation condition and indoor‑outdoor temperature difference. For heavy salt‑spray coastal areas, select PU sandwich panel with high‑weather‑resistance coated steel or stainless‑steel face sheet. For inland plum‑rain‑affected factories, high‑quality weather‑resistant color‑coated PU sandwich panel is acceptable. Simply thickening foam core cannot solve corrosion and water‑penetration problems. SAMZOON delivers targeted selection solutions and provides free samples for physical quality check.
📦 Step 2: Incoming acceptance & storage of PU sandwich panel, avoid moisture risk from source Check PU sandwich panel upon arrival: face coating integrity, edge sealing workmanship, foam compactness and surface collision damage. Store PU sandwich panel in ventilated and dry area, elevate panels with blocks to isolate ground moisture. Keep original moisture‑proof packaging film intact as long as possible. Avoid unloading PU sandwich panel on rainy days. Wet PU sandwich panel must be fully dried before installation, otherwise hidden blistering risk will remain.
🔧 Step 3: On‑site cutting & edge sealing, block moisture invasion path Minimize on‑site cutting of PU sandwich panel, factory pre‑cut fixed‑size PU sandwich panel is preferred. If on‑site cutting is unavoidable, fully seal cut ends immediately after cutting. Never expose bare PU foam core under humid or salt‑spray atmosphere. Completely clear cutting debris to prevent electrochemical rust on panel surface. SAMZOON provides construction guidance to standardize on‑site sealing operations.
🧱 Step 4: Installation construction, focus on high‑risk corrosion joints Fit anti‑corrosion gaskets for all screws of PU sandwich panel. Ensure panel surfaces are dry and clean before applying high‑humidity‑resistant sealant; keep sealant continuous and gap‑free. Add waterproof pressure strips for exterior panel seams. Pay close attention to cut ends, screw holes, door‑window connections and internal‑external corners — these are high‑risk positions for salt‑spray and moisture to penetrate into PU sandwich panel. Do not carry out gluing work under heavy fog or rainy weather.
🧪 Step 5: Completion inspection, moisture‑proof & anti‑corrosion acceptance before handover Carry out full‑surface inspection after PU sandwich panel installation. Check panel scratches, sealant bubbles or gaps, full sealing status of all cut ends and screw‑point coating damage. Do not ignore hidden positions for coastal high‑humidity projects. Familiar with acceptance standards for South‑China clean‑room and factory projects, SAMZOON supplies acceptance checklist references.
🛠️ Step 6: Post‑project operation & maintenance, regular inspection under plum‑rain and salt‑spray conditions Establish regular inspection schedule after project commissioning. Fully check PU sandwich panel before and after every plum‑rain season. Observe surface rust spots, aged or cracked sealant and screw corrosion. Repair damaged coating and cracked sealant timely. Replace local PU sandwich panel when blisters keep expanding to prevent large‑scale deterioration. Increase inspection frequency for coastal salt‑spray projects.
⚠️ Step 7: Common pitfalls for high‑humidity coastal projects
- Only thicken PU sandwich panel foam core while ignoring face‑sheet anti‑corrosion grade and edge sealing;
- Assemble PU sandwich panel directly after on‑site cutting without end‑face sealing;
- Apply sealant on wet surface or during rainy days;
- Place PU sandwich panel directly on ground without elevation;
- Adopt ordinary sealant not suitable for salt‑spray and high‑humidity working conditions.
SAMZOON has abundant finished project cases for South‑China coastal high‑humidity scenarios. For complex working conditions, consult us for technical support and fast‑track production of customized stainless‑steel composite PU sandwich panel.
