Cooling water exchangers are often the hidden bottlenecks in refinery and petrochemical plant reliability. Scaling, fouling, and corrosion not only reduce heat transfer efficiency—they can force costly unplanned maintenance and lower overall unit performance.
Curran International’s thin-film hydrophobic Tube ID coatings are helping plants extend run times, reduce maintenance frequency, and protect exchanger tubes from scaling and water-side corrosion.
The Challenge: Persistent Fouling & Scaling
Hot hydrocarbon product streams (often >225°F on the shell side) accelerate mineral scaling on the cooling water side—especially in low-flow or overloaded circuits.
These “bad-actor” exchangers:
- Require frequent pull-and-clean maintenance mid-run
- Cause operational bottlenecks and reduced duty
- Drive up repair costs due to recurring leaks and corrosion
The Solution: Thin-Film Hydrophobic Coating
Curran applies a 12-mil average thickness hydrophobic coating that:
- Resists scaling and biofouling
- Maintains water contact with the heat-transfer surface
- Minimizes boundary-layer drag for better flow
Initially, coated and uncoated exchangers perform similarly. But over time, coated exchangers sustain higher duty, thanks to smoother internal surfaces and reduced fouling.
Proven Results in the Field
Client reports show measurable, repeatable benefits:
- Texas fractionation plant — eliminated bi-annual tube cleaning on large shell-and-tube units.
- Gulf Coast refinery — reduced leaks and mid-run blinding of problematic cooling water exchangers.
- Oil sands upgrader — doubled uninterrupted exchanger run times between turnarounds.
Coating Options for Cooling Water Service
- Curran 1000T — Workhorse for cooling water; two-coat system; rapid turnaround; suitable for new or used exchangers.
- Baked phenolic — 4–6 coats for pinhole-free finish (<10 mils); shop-applied; for cooling water and certain chemical services.
- Fluoropolymers (PFE, PTFE) — For hot, corrosive services; shop-applied with 650°F bake-cure.
Case Study: Midwest Refinery Side-by-Side Test
During a turnaround, the refinery installed both coated and uncoated U-tube bundles. After four years:
- Coated exchanger — No scale, minimal debris; no hydro-lancing needed; coating intact.
- Uncoated exchanger — Required hydroblast cleaning; RFT inspection showed >70% wall loss in multiple tubes.
The coated bundle maintained water-side integrity, reducing corrosion risk and enabling easy cleaning with simple backwashing.
scale and fouling. A minor amount of cooling tower debris was rinsed from tubesheet. The coated exchangers did not require hydro-lancing and images were taken in as-is condition. The coating was in good condition, and no RFT inspection performed.
cleaning of cooling water foulant and scale. RFT inspection was performed on the tube IDs. The inspection found tubes with 70% indications after just four-years of service.
Why It Works
- Full-circumferential coverage via proprietary application methods
- Inert, non-reactive barrier against cooling water chemistry
- Sustained flow rates, even near 3 FPS operating conditions
Protect your exchangers. Reduce downtime. Improve reliability.
📧 Contact Curran International for more information on Tube ID coatings: info@curranintl.com
📞 (281) 339-9993
