Nine hundred knurled-L (KLL) finned tubes in stainless steel for a refinery air cooler retrofit where the existing bundles had failed in service.
The problem
The refinery’s original air cooler bundles used L-foot aluminium fins that had loosened after several years of thermal cycling, and the resulting loss of air-side performance reduced throughput. The replacement had to fit the same bundle envelope — no changes to the fan, plenum or headers were possible.
The solution
| Item | Specification |
|---|---|
| Quantity | 900 tubes |
| Type | KLL — knurled L foot, full coverage |
| Base tube | Stainless steel 316L, 25.4 mm OD × 2.0 mm |
| Fin | Aluminium 1060, 12.7 mm height, 3.2 mm pitch |
| Length | 6,000 mm finned, bare ends per drawing |
Why KLL
The knurled foot grips the base tube more firmly than a plain L foot, which matters in a hot, vibrating air cooler. Full coverage also protects the stainless tube from chloride attack in the cooler’s coastal location.
Delivery
Tubes were produced, inspected and packed in sea-worthy cases in 24 days, with dimensional reports for every bundle.
Need a retrofit that fits an existing bundle?
Tell us the tube diameter, fin height, fin pitch, materials and quantity — we reply with price and lead time within one working day.