Stainless Steel Centrifugal Fans

Different applications require different levels of weld finishing and surface preparation. Atmax stainless steel fan packages can be supplied with multiple weld finish options.

1. Standard Finish – As Fabricated

This is the most economical option and is suitable for general industrial ventilation applications.

Features:

• Weld splatter removed
• Continuous welds on fan housing seams
• Welds may contain minor pits, scratches, crevices, or small pockets typical of fabricated stainless steel
• No specific micro-finish requirement

This option is commonly used for:

• Industrial exhaust ventilation
• Chemical fume extraction
• Dust collection systems

2. Plus Finish – Continuous Weld with Improved Surface

This option provides improved weld quality and surface preparation compared to standard fabrication.

Features:

• Weld splatter removed
• Continuous weld construction
• Welds ground to reduce surface imperfections
• Improved surface smoothness

This finish is recommended for:

• Corrosive air handling
• Food processing exhaust
• Pharmaceutical facilities

3. Deluxe Finish – Polished Weld Surface

For applications requiring improved cleanliness and smooth surfaces, welds are further processed.

Features:

• Welds ground to reduce surface imperfections
• Welds polished to approximately 125 RA micro finish
• Reduced surface roughness improves cleanability
• Lower risk of particle accumulation

This option is suitable for:

• Food processing plants
• Clean manufacturing environments
• Pharmaceutical exhaust systems

4. Premium Finish – High Polished Surface

The premium finish offers the highest surface quality for stainless steel fan construction.

Features:

• Welds polished to approximately 250 RA micro finish
• Smooth surface profile
• Improved corrosion resistance and cleanability

Premium finishing is typically used in:

• Hygienic process ventilation
• High cleanliness industrial applications

Passivation of Stainless Steel Components

Passivation is an optional surface treatment used to enhance corrosion resistance.

During manufacturing processes such as machining and welding, free iron particles may become embedded in the stainless steel surface. If not removed, these particles can oxidize and create rust-like stains.

Passivation works by:

• Dissolving embedded iron contaminants
• Restoring the natural chromium oxide layer of stainless steel
• Improving long-term corrosion resistance

Passivation is commonly specified in chemical, pharmaceutical, and high-purity processing facilities.