Cleaning and Inspection Challenges No.6

Author: Mike Watson, Managing Director, Tube Tech

Following a recent survey of refinery operators from across the world Tube Tech have compiled the Top 10 cleaning and inspection challenges faced by the refining industry.

As a world leading specialist industrial cleaning contractor Tube Tech have solved some of the refining and petrochemical sectors most difficult cleaning challenges. Tube Tech asked over 2500 refinery operators to complete their survey and the Top 10 cleaning and inspection challenges were developed as result of the survey feedback.

Below is the 6th most common cleaning and inspec­­tion challenge faced by the refining sector.

No 6       U-Tube (Hairpin) Heat Exchanger Cleaning

U-Tube (Hairpin) heat exchangers, occasionally called a multi-tube, formed as G-fin or double-pipe exchangers, are one of the most popular heat exchanger configurations across heavy industry.

Double-pipe (pipe-in-pipe) or multi-tube heat exchanger of a two-leg bundle where each leg has its own separate shell are a challenge to clean using traditional water jet and chemical cleaning techniques.

U-Tube heat exchangers contain hundreds of small bore tubes which can contain varying deposits along the straight and curved radii. The shell side of hairpin heat exchangers are also liable to deposit formation within the narrow 6mm spacing of the square pitch, so the cleaning challenge becomes even greater.


  • Scale and blockages restrict production throughput as well as heat transfer leading to compensation within other heat transfer assets downstream
  • Traditional high pressure water jetting techniques struggle to clean hard to reach areas on the shell side and around the hairpin bends
  • No traditional technology exists to unblock and clean tenacious carbon and coke fouling that forms within the “U” bends or from the external shell side tube surfaces.
  • Chemical cleaning does not negotiate blockages within hairpin heat exchangers plus presents increased waste disposal and environmental issues
  • Manual and even remote High-pressure water jetting can be slow and dangerous when cleaning blockages due to risk of hydraulic recoil on both rigid and flexible water jetting lances.
  • Flexible and rigid high-pressure water lances are unable to negotiate hairpin bends nor thoroughly clean the external shell side tube surface of any square pitch shell and tube exchanger.


Heat Exchanger Cleaning Solutions (Tube AND Shell Side)

  • Micro DarTT and Shell Jett, simultaneously cleans both the U-tube and External Shell Side of both straight and hairpin shell and tube heat exchangers
  • IRIS standard cleanliness is now assured first time every time using Tube Tech’s latest enhanced tube polishing system.
  • Our 3D animation service provides a virtual reality of the project clearly demonstrating the layout and technology to sceptical clients.



Recognised worldwide as leaders in the industrial cleaning field, Tube Tech has spent the past thirty plus years engineering solutions to improve on traditional water jet and chemical cleaning methods. Cleaning U-Tube (Hairpin) heat exchangers was such a challenge and for which several systems have been perfected.  From the cleaning of titanium and stainless steel condenser tubes and carbon steel heat exchanger tubes to more exotic metal tubes during refinery shutdowns and petrochemical turnarounds Tube Tech are renowned as heat exchanger cleaning experts and are pleased to assist you with the cleaning of any straight, hairpin even coiled heat transfer plant.