Condenser Tube ID Coating

Condenser Tube ID Coating

History of Condenser tube coating Technologies

Condenser tube coating (tube lining), as we know it, began in Europe in the mid-twentieth century, using a “flood and drain” method to coat tubes with phenolic materials. This remained the only option until the mid-1980s, when spray applications were first tried.

Using air pressure to atomize material, condenser tubes were coated with a spray application of engineered polymers. This technique proved to be much simpler and less time-consuming than the fill/drain/rotate method prevalent at the time. With the development of this patented method, Curran International changed the industry standard for condenser tube coatings, applying the polymer tube lining system to the full circumferential inner diameter (ID) of a small tube with a uniform, homogenous layer of material. Curran’s condenser tube lining can be done in our Houston, Texas shop or on-site around the world.

Typical turnaround for a Condenser 35,000 tube by 30 ft long

  • 30-60 day lead time
  • 2-3 weeks

This system was first demonstrated in the U.S. at a Florida utility station, where through wall corrosion in the piping had prematurely shortened the life of a steam condenser. The utility, together with the Electric Power Research Institute (EPRI), began to research epoxy coatings for tube IDs as an alternative to costly, time consuming alternative methods of repairing their condenser.

The study verified the efficacy of tube lining, which proved less susceptible to fouling compared to uncoated tubes. Condenser tubes with coatings also held up under sustained heat transfer better than uncoated tubes.

The economic benefits rapidly gained traction when petrochemical refineries applied thin film coatings (thin film tube lining) to the tube id’s in its heat exchangers. Clients with “bad actor” exchanger bundles found that thin-film polymer coating eliminated normal maintenance as a result of reduced foul attachment and corrosion deposits. This in turn improved operational efficiency and favorably impacted profit margins.

Curran International patented its spray applied Condenser tube lining system in 1996. Its many clients include the major refineries and power-gen plants around the world.

Thin Film Heat Condenser Tube Coatings

Thin film polymer tube lining materials, applied at <10 mils or 250 microns, provide a foul release suited for all water services. The coating also provides a barrier to any corrosion that tends to occur on bare tubes.

Condenser tube coatings (Condenser tube linings) have proven to reduce fouling and boundary layer drag. By promoting flow, backpressure is reduced and the long-term optimal performance of heat transfer equipment is sustained. Coatings are chosen according to the service temperature and conditions in which they are to be applied, as well as where – in the field or in-shop.

Used condenser tube repair and recovery of leaking tubes

Get your used condenser to the next scheduled outage or shut down, with tube ID coating. Curran’s method for applying Condenser tube coating can also be applied to used condenser tubes to repair them. Curran can repair your condenser tubes, by removing all of the scale from the tube wall (including deep pits) and applying its tube lining system to cover any pits and the tube wall. What you are left with is a fully enclosed coating system that will prevent any further corrosion, and will also eliminate fouling.

Curran also has a process for recovering known leaking tubes (tube with holes). There is service history of recovering tubes with a 1.5mm diameter hole. Once the tube recovery procedure is applied, each tube is tested up to 80 PSI.
Click here to receive a quote to repair your exchanger tubes

Bottom line

Application of polymer coatings to the ID of condenser tubes can:

  • Increase heat transfer duty
  • Eliminate corrosion
  • Reduce or eliminate micro and macro fouling
  • Reduce normal maintenance and improve the “useful life” of fixed assets.

Some chemical exposures, elevated temperatures or high fluid/gas velocities can limit coatings, but great benefits can be achieved by applications within acceptable temperature parameters and exposures appropriate to the applied coating.

The many advantages of tube lining systems include

The many advantages of tube lining systems include

  • Cost savings that can amount to millions of dollars per year (See paper presented by gulf coast refinery at NACE 2005)
  • Perpetual equipment life
  • Energy savings
  • Throughput efficiency gains
  • Savings in comparative cost of entirely replacing tubing with expensive steel alloy pipes.
  • Exchanger coatings can eliminate any copper discharge.

Typical procedure

  • Evaluation of any chlorides or MIC and remediation of these contaminants
  • Condenser tubes are grit blasted to clean tubes and create a surface profile (verified with a video probe (Pits are also verified clean with video probe)
  • Condenser tubes are cleared of any grit
  • Condenser tube lining process begins and multiple coats (depending on the severity of the pitting and conditions that the condenser tube faces) are applied.
  • The condenser is properly cured and returned to the client