Introduction
In the design and construction of Class 100 cleanrooms, the connection between walls and ceilings is one of the critical nodes to ensure cleanliness standards are met. Today, I will provide a detailed analysis of a typical wall-ceiling connection detail for Class 100 cleanrooms, focusing on its structural composition, material selection, and key construction points.
Detailed Analysis of the Connection Detail
1. Main Components
This connection detail primarily consists of the following key components:
Soft Polyurethane Sponge: Acts as a cushioning and sealing material at the joint.
Aluminum Allogy Corner Column: Forms the skeleton structure of the connection.
Aluminum Alloy Base Channel: Provides fixing and support.
Sealant: Ensures the final air-tightness.
2. Layered Construction Breakdown
2.1 Base Treatment
First, embedded parts or mounting bases are installed at the top of the wall to ensure sufficient load-bearing capacity for the entire ceiling system. The base surface must be flat, dust-free, and free of oil stains to ensure proper adhesion of subsequent materials.
2.2 Installation of Aluminum Alloy Base Channel
The aluminum alloy base channel is fixed to the top of the wall using stainless steel bolts or specialized connectors. Key installation considerations include:
Level tolerance controlled within ±1mm/m.
Tight alignment at joints, with gaps not exceeding 0.5mm.
Fixing point spacing should not exceed 600mm.
2.3 Soft Polyurethane Sponge Installation
Soft polyurethane sponge is laid over the aluminum alloy base channel, serving the following functions:
Cushioning vibration transmission.
Aiding in sealing.
Compensating for structural deformation.
The sponge should be installed continuously, with joints cut at an angle and sealed using specialized tape.
2.4 Installation of Aluminum Alloy Corner Column
The aluminum alloy corner column is a key transition component connecting the wall and ceiling, featuring:
Specialized cleanroom profiles with anodized surfaces.
Internal radius compliant with cleanroom non-accumulation requirements.
Snap-fit connection with the base channel for easy disassembly and maintenance.
Special attention must be paid to the joint treatment between the corner column, wall panels, and ceiling panels.
2.5 Sealant Application
Finally, neutral silicone sealant is applied to all joints to form a complete airtight barrier. Key points for sealant application:
Surfaces must be cleaned before application to ensure they are dust-free and oil-free.
Sealant width should ideally be 6-10mm.
Specialized tools should be used to shape the sealant into a concave arc.
Maintain a clean environment during curing.
Material Selection Criteria
1. Soft Polyurethane Sponge
Density: ≥25kg/m³.
Resilience: ≥60%.
Fire rating: At least B1 grade.
Aging resistance: No significant deformation after 168 hours at 100°C.
2. Aluminum Alloy Profiles
Material: 6063-T5 or higher grade.
Surface treatment: Anodized coating thickness ≥15μm.
Dimensional tolerance: ±0.2mm.
Straightness: ≤0.3mm/m.
3. Sealant
Type: Neutral-cure silicone sealant.
Movement capability: ≥25%.
VOC content: ≤50g/L.
Mold resistance rating: Grade 0.
Key Quality Control Points for Construction
Dimensional Control: All joint gaps should be uniform, with cumulative error not exceeding 2mm.
Clean Construction:
Maintain positive pressure in the work area.
Use dust-free tools.
Clean as you work.
Air-Tightness Testing:
Conduct pressure decay testing.
Leakage rate ≤0.1%/h at 1000Pa pressure difference.
Surface Treatment:
No visible scratches or dents.
Uniform color and finish.
Smooth joints without abrupt changes.
Common Issues and Solutions
Issue 1: Dust Accumulation in Corners
Cause: Insufficient internal radius or rough surfaces.
Solution: Use corner columns with R≥30mm and surface roughness Ra≤0.8μm.
Issue 2: Joint Cracking
Cause: Mismatched thermal expansion coefficients or insufficient sealant movement capability.
Solution: Use high-elasticity sealant and leave appropriate expansion gaps.
Issue 3: Vibration Transmission
Cause: Insufficient compression of the polyurethane sponge.
Solution: Increase sponge thickness or density to ensure 15-20% compression.
Conclusion
The connection between walls and ceilings in a Class 100 cleanroom may appear simple, but it involves multiple precision designs and strict construction requirements. Only through proper material selection, precise structural treatment, and rigorous construction control can this critical junction maintain long-term sealing performance and cleanliness assurance. I hope this article proves useful to professionals involved in cleanroom design and construction, and I welcome further discussion on practical experiences.
Frequently Asked Questions (FAQ)