Heat exchanger tubes are vital assets to the power, O&G, mining and chemical plant sectors, helping to moderate the temperature of fluids and gases throughout plants and processes for optimal performance and safety. In order to maintain heat exchanger tubes in optimum condition, regular non-destructive testing (NDT) is crucial for the detection of flaws that may lead to poor heat transfer and increased operating costs. Routine inspection not only helps to avoid sudden failures but can help extend the life of your tubular heat exchangers. Learn more about the importance of regular testing below.
Prevention Is The Best Protection
Given the function of heat exchanger tubes, it’s little surprise that they can be prone to a wide range of degradation processes. With constant heating and cooling cycles occurring, these tubes are under severe operating conditions and can face significant wear over time. Common issues to look for include:
- Internal and external corrosion
- Erosion on inlet ends, tube to tube erosion, condensate grooving and baffle wear
- Fatigue cracks
- Pitting caused by process liquids and gases
- Physical damage caused by handling on turnarounds
If left untested, such issues can lead to costly and substantial damage to your exchangers, as well as safety risks for property and personnel. Inspections of each heat exchanger helps operators decide the next steps for repair and preventative maintenance, giving your team peace of mind and time to plan ahead.
Breaking Down The Main Culprits
As mentioned above, there are no shortage of factors that can begin to affect the performance of heat exchangers. Issues such as pitting, corrosion, and erosion can pose significant risks. Where pitting is typically the by-product of a concentrated electrochemical gradient of oxygen and carbon dioxide. Pits tend to form in cold fluids, where erosion and corrosion are more prevalent in tubing where steam and water are at play. Finally, chemical corrosion is caused by gasses or caustic chemicals gradually wearing down the wall thickness of heat exchanger and boiler tubes, leaving them vulnerable to failures.
Cracking is another common issue, frequently appearing in bends, along the top edge of support plates, at tube sheet expansion transition points, on the roots of fins, and more.
Denting can occur as the result of corrosion build up between tubes and baffle plates, as well as the tube support sheet. Left undetected, these dents can cause stress corrosion cracks or fatigue cracking. Fretting and Wear can also occur due to the vibration that causes tubes to rub against the baffle or saddle support. Fretting wear can be particularly damaging and lead to failure, making inspection essential to catch it before it has the chance to progress.
Heat Exchanger Inspection With Russell NDE
As a leader in the NDT field, Russell NDE is able to assist with the inspection of heat exchanger tubes and more. With advanced Eddy current testing technology that utilizes our EasyLogPro software, detecting faults is simple. Recent updates to EasyLogPro makes it easy to create a tube sheet map simply by taking and importing a photograph, making things even easier and more efficient than before!
For all your NDT inspection needs, contact Russell NDE today.