Tubing Inspection

Sentinel Integrity’s Tubing Inspection Service Line maintains a staff of fully qualified and highly trained tubing data analysis and acquisition technicians. They are capable of evaluating and inspecting your heat exchanger tubing assemblies using a variety of modern tubing inspection applications. We utilize highly advanced equipment, data analysis, and reporting software within the industry.

Sentinel utilizes the following inspection methods for heat exchanger inspections: eddy current testing, remote field testing, near field testing, flux leakage testing, internal rotary inspection system, and surface eddy current testing.

Eddy Current Testing (ECT)

Application: Non-magnetic tubing (i.e. stainless, brass, titanium, etc.)

  • Bobbin Coils - most common technique
  • U-Bend inspections
  • ECT array tubing inspections

Remote Field Testing (RFT)

Application: Ferromagnetic tubing (i.e. Carbon steel, 400 series stainless, etc.)

  • Bobbin Coils - most common technique
  • Boiler inspections
  • U-Bend inspections

Near Field Testing (NFT)

Application: Ferromagnetic externally finned tubing

  • Near field array (NFA) improved ID pit sizing and C-Scan imaging

Flux Leakage Testing (FLT)

Application: Ferromagnetic externally finned tubing

  • ID corrosion / erosion detection and sampling
  • OD isolated corrosion detection and sizing
  • Defect orientation determination (ID vs. OD)

Internal Rotary Inspection System (IRIS)

Application: Inspection of ferromagnetic tubing and non-magnetic tubing

  • C-Scan, B-Scan, and D-Scan displays
  • Complimentary to electromagnetic techniques (ECT, RFT, NFT, and FLT)

Surface Eddy Current Testing

  • Eddy Current Array
  • Conventional pencil probes

Sentinel Integrity Solutions Tubing Inspection Division utilizes advanced reporting software that is considered to be unsurpassed within the industry. Using this software, Sentinel’s highly trained staff can very quickly generate a highly detailed and concise report. These reports are considered to be some of the most professional reports within the industry.

Preliminary Reports

After the inspections and final data analyses are complete, a preliminary report is immediately generated. This report consists of a tube sheet diagram with the tubes inspected and is color coded to a percentage wall loss. In addition, supplemental tube sheet diagrams can be included as well, showing the worst case scenarios for tube plugging or selective re-tubing.

Final Reports

Formal reports consist of a detailed description of the inspection findings, a summary of the test results, tube sheet diagrams, 3D views of the exchanger, detailed information on each tube inspected, along with screen captures of the typical indications found.

Upon completion of our final reporting, our tubing specialists will offer an electronic data file in conjunction with our "viewer application" that will allow the user to perform custom 3D views of the examined bundle. This includes the ability to rotate, roll, pan, and zoom allowing for precise location of damage or anomalies.

Sentinel's advanced reporting and viewer application have a history of supporting high level evaluations including reliability and operational assessments, risk based inspection evaluations on the bundle, and design or re-design considerations by operations or corrosion engineering for eliminating the damage detected.


6606 Miller Road 2
Houston, Texas 77049
Office: (281) 457-2225
Fax: (281) 457-0225


3038 Leopard Street
Corpus Christi, Texas 78408
Office: (361) 887-2014
Fax: (361) 887-2022


1954 West Shore Avenue
Port Allen, Louisiana 70767
Office: (225) 421-8640
Fax: (225) 421-8645