Why Pitch Matters When Selecting Rigid PVC Cooling Tower Fill

When customers compare cooling tower fill, they often focus on width and length first.

Those dimensions are important, but there is another number that deserves attention: pitch.

Pitch helps define the spacing and geometry of the corrugated passages inside the fill. Changing it can therefore change the physical characteristics of the fill even when the outside dimensions remain similar.

What Pitch Actually Changes

The pitch describes the spacing pattern formed by the corrugation of the fill sheet.

It influences the size and arrangement of the passages through which water and air move. Together with corrugation angle and sheet geometry, it forms the internal structure of the heat-transfer media.

This is why I would not recommend replacing an existing fill solely because the new product has the same width and length.

16.5mm Pitch for Project-configured Fill

Some projects are designed around a specific fill geometry from the beginning.

For these applications, project-configured cooling tower fill with 16.5mm pitch can be considered when the tower dimensions and required internal structure have already been established.

The important point is that the pitch should be treated as part of the complete design rather than as an isolated specification.

Why Two Pitch Options Can Be Useful

Replacement projects do not always have the same operating or dimensional requirements.

In some cases, the tower layout or existing fill configuration may call for a different pitch.

A product such as cross-flow fill media with dual pitch options provides more flexibility when different cross-flow projects require different internal geometries.

19mm Pitch for Wider Installation Options

For another group of projects, a 19mm pitch configuration may be appropriate.

For example, 19mm pitch rigid cooling tower fill with 750mm and 930mm widths combines a defined pitch with two available widths.

This type of configuration can be useful when the tower layout requires dimensional flexibility without changing the basic fill geometry.

Do Not Compare Pitch in Isolation

A smaller or larger pitch should not automatically be described as better.

The correct choice depends on the tower type, airflow, water loading, fill depth, water quality, and required thermal performance.

In a replacement project, the existing fill geometry is especially valuable information because it tells us what the tower was originally designed around.

Our Practical Check

When we receive a fill replacement inquiry, we normally want to confirm:

• Existing pitch
• Corrugation angle
• Width and length
• Fill depth
• Sheet thickness
• Tower type
• Water and airflow arrangement

Once these details are confirmed, the pitch becomes much more meaningful.

For rigid PVC fill, the goal is not simply to choose a pitch number. The goal is to reproduce or improve the required flow geometry while making sure the complete fill assembly fits the tower.