Pillow Plate vs Dimple Plate

In industrial heat transfer applications, the terms pillow plate and dimple plate          are often used interchangeably. However, while they share similarities, they are not identical in structure or performance.

1. What is a Pillow Plate ?

A pillow plate is manufactured by laser welding two thin stainless steel sheets together in a specific weld pattern.          After welding, the plate is hydraulically inflated, forming a three-dimensional internal flow channel.

The inflated structure creates a “pillow-like” shape.

Key Characteristics:

• Two welded stainless steel sheets
• Hydraulically expanded internal channels
• High turbulence surface
• Strong fouling resistance
• Suitable for high-pressure operation

Common Applications:

• Falling film evaporators
• Tank heating and cooling jackets
• Immersion heat exchangers
• Condensers
• Food & beverage equipment

2. What is a Dimple Plate?

A dimple plate is typically made from a single sheet that is mechanically stamped to create protrusions.          It may also refer to lightly welded plates without hydraulic inflation.

• Shallower flow structure
• Lower turbulence
• Commonly used as tank jackets
• Limited pressure resistance

3. Differences Between Pillow Plate and Dimple Plate

In summary:

• Pillow plates are structurally stronger and more efficient.
• Dimple plates are simpler and used in lower-duty applications.

4. Working Principle of Pillow Plate Heat Exchanger

Heat transfer occurs indirectly between two media separated by stainless steel sheets.

• Fluid 1 flows inside the inflated channels.
• Fluid 2 flows outside the plate surface.
• Heat transfers through the thin wall.
• Inflated geometry creates turbulence.

Advantages:

• High heat transfer efficiency
• Reduced fouling
• Compact structure
• Flexible modular design

5. When to Choose Pillow Plates?

• High pressure applications
• Significant fouling risk
• Hygienic design required
• Custom tank integration
• Large heat transfer surfaces

Conclusion

Pillow plates and dimple plates differ significantly in structure, strength, and performance.          For demanding industrial applications, pillow plate heat exchangers are generally the preferred solution.