CTI | A KELVION COMPANY
CTI is the global leader in repairing and restoring heat exchanger tubes and providing increased reliability to damaged or new equipment. In 2018, CTI was acquired by Kelvion. Whether you are dealing with leaks caused by localized erosion/corrosion at the tube ends or throughout the entire tube length, CTI’s Shield/Seals™ and Full-Length Tube Liners™ can extend the life of your heat exchangers to avoid costly down-time or bundle replacement. Save money and increase reliability with life extension solutions.
We recognize that for most of our clients, any amount of unplanned downtime results in unexpected costs well beyond just the repair. Our repair techniques can greatly reduce the time off-line minimizing significant downtime losses. Whether aboard a vessel or rig off-shore, or in a refinery in a remote location, CTI has the resources and capabilities, including minimal material lead-times, to provide a rapid response to your emergency repair needs.
Shield/Seals repair damaged and/or leaking tube ends and prevent unnecessary retubing or plugging. Why replace the entire tube when only the first 20-30 cm are worn? They are also commonly installed in new heat exchanger tubes to prevent damage that can lead to leaking/plugged tubes. Shield/Seals can repair/restore tubes suffering from I.D. and O.D. corrosion at inlet or outlet tube ends.
The installation is done by using two methods:
- Mechanical Expansion
- CTI’s Full Length Hybrid Expansion
Full-Length Tube Liners are designed to restore tubes that are suffering from isolated or full-length corrosion (pitting, cracking). Leaking or damaged tubes requiring plugging are returned to service. Reduced fouling of Liners increases efficiency over plain carbon steel tubes. Tube Liners are designed into new heat exchanger builds to increase reliability and extend service life expectancy. Eliminating tube leaks in between turnarounds and avoiding emergency shutdowns to plug are proven cost savings benefits.
In cases when heat exchanger tubes are fouled or plugged with debris / solids, Kelvion offers several tube cleaning services to return the heat exchanger to original design flow conditions, including:
- Removing mud and obstructions (Jet-brush)
- Light scale (rotatory cutter/buffer or metal bladed cleaners)
- Heavy duty deposits (water tube drill)
The CTI Shield/Seal™ is a thin walled metallic tube insert made of highly durable alloys. For tubes suffering from inlet-end erosion/corrosion, Stress Corrosion Cracking, crevice corrosion or any problems related to the tube-ends, Kelvion offers its most cost-effective tube repair, the CTI Shield/Seal™, ranging in length from 4 inches to 14 feet (100mm to 4270mm) long.
Kelvion has two methods of expansion on for our Shield/Seals. Mechanical expansion involves expanding the Shield/Seal at the first inch (25mm), within the tube sheet and also the last inch (25mm), the discharge end. The mechanical expansion will effectively bridge any leak path or damage between the first and last inch (25mm) of the Shield/Seal.
CTI’s Shield/Seal is a proven and effective repair process for problems related to inlet and outlet tube ends with I.D. or O.D. damage.
On certain Shield/Seal installations we use CTI’s hybrid expansion method which combines full-length hydraulic expansion of the Shield/Seal followed by our mechanical expansion. Hybrid expansion will eliminate the gap that may exist between the unexpanded portion of Shield/Seal and the tube. This is typically used on high temperature, high-pressure and long length applications.
Common failure mechanisms include
- Tube-end erosion/corrosion
- Stress corrosion cracking
- Crevice corrosion
- Localized pitting
- Ammonia grooving
- Reinforced tube-to-tube sheet joints
And CTI Shield/Seals can be provided in from almost any alloy from “A to Z”, Admiralty Brass to Zirconium.
Heat exchanger tubes also suffer from a variety of full-length issues, such as pitting or cracking, or full-length wall loss. In this situation our Full-Length Tube Liners™ can be a very attractive alternative to a partial or full re-tube. The thin-walled Full Length Tube Liners are an effective way to ensure long-term reliability and can be installed into existing tubes or into NEW tubes.
How they work
Tube I.D.s are measured to correctly size the tube liner. Prior to installation the tubes are cleaned and dried and the tube liners are inserted into the tubes. Using our custom-made pumps they are hydraulically expanded throughout the full length of the parent tubes. The liners are then cut, trimmed and mechanically expanded at the tube ends of each tube sheet, resulting in fully restored tubes.
CTI’s Full-Length Tube Liners can ensure long-term reliable, uninterrupted production on critical heat exchangers, and prevent potential shutdowns from tube leaks.
- Restoring previously plugged, leaking tubes to service will recover failed heat exchangers and extend the heat exchanger life.
- Corrosion resistant Full-Length Tube Liners can reduce fouling and increase efficiency.
- Kelvion is able to perform this service as an emergency response on failed equipment in-situ.