A higher open-area ratio than standard tube sheets — more holes relative to solid plate area, for designs that need maximum tube density, with ligament efficiency managed carefully against the thickness calculation.
| Structural Principle | Maximized hole density; ligament efficiency at the weakest row governs thickness |
| Typical Open Area | Higher than standard patterns — confirmed per design |
| Design Constraint | Minimum ligament width must satisfy the governing code calculation |
| Best Suited For | Maximum heat-transfer-area designs within a fixed shell diameter |
| Governing Codes | TEMA/ASME ligament efficiency requirements |
Any material and most structural types can be built with a high open-area pattern; thickness must be checked accordingly.
There's no fixed percentage — it's driven by the specific tube count and pitch the design calls for, always checked against the minimum ligament efficiency the governing code requires at that pressure class.
Often yes — as ligament efficiency drops with tighter hole spacing, the code calculation frequently requires additional thickness to maintain the same pressure rating, which is a real trade-off against the added tube density.
The practical ceiling is set by the ligament efficiency the code allows at the required pressure and material — beyond that, either more thickness or a larger diameter is needed to fit the desired tube count safely.
Every enquiry is checked against governing code, material compatibility and manufacturing feasibility before a quote is issued. Use our product, material, grade and standards guides to freeze the RFQ — then confirm with engineering.
Send your diameter, material, pressure class and quantity — we'll confirm thickness and price.