During the last 20 years, Koch Heat Transfer Company's TWISTED TUBE® heat exchangers have made their way into the refining, petrochemical, and chemical industries. TWISTED TUBE® heat exchangers come in a variety of sizes, from 3/8" to 1 1/4" in diameter, with material types such as stainless, titanium, brass, monel, carbon steel, duplex, and nickel – just to name a few.
One advantage of utilizing TWISTED TUBE® heat exchangers is the absence of baffle supports, which allow them to have the highest heat transfer coefficient of all tubular heat exchangers (up to 40 percent higher). Recent innovation and development of new technology – such as the twisted probe – has evolved greatly over the last two years thanks to collaboration with other industry leaders.
The inspection of shell-and-tube heat exchangers is commonly performed with Eddy Current Testing (ECT), which can be used on non-magnetic (nonferrous) and slightly magnetic alloys that are conductive such as: stainless, brass, titanium, hastalloy, Inconnel, etc. Eddy Current Testing can detect small defects such as stress corrosion cracking and has been successful in the inspection of such important assets.
- Inspection of non-ferromagnetic tubing, such as stainless, brass, titanium, etc.
- Can distinguish between I.D. and O.D. defect orientation
- Defect location distinguishes whether defect is in outer crest or lower dip of twisted tube
- Sensitivity to gradual wall loss, corrosion, pitting, erosion, cracking, and more
- Can Inspect .750" up to 1" diameter tubing (smaller or larger tube diameters require special probe design)
Approved Service Provider
- Increased efficiency thanks to high rate of inspection (60-80 tubes per hour)
- Repeatability allows for comparing historical test results to establish corrosion rates and remaining life
- Quality work thanks to highly trained and qualified ECT technicians
MISTRAS Group is the only approved vendor that provides highly qualified, trained Eddy Current technicians for the inspection of TWISTED TUBE® heat exchangers utilizing this new inspection technology. This includes on-site and in-house data analysis, utilizing the most advanced state of the art software for ECT (Eddyfi Ectane™ system
and Magnifi® software
). This equipment allows the technician to accurately and confidently inspect twisted tubing in real-time, by enabling full-length recording capabilities. This allows data analysis offline to assess damages with the customer.
A 2D and 3D formal report contains a cover sheet, table of contents, introduction, executive summary, tube sheet layouts, data summary sheets, detailed data sheets, & graphic printouts.