Retubing condensers

Retubing Condensers

Retubing condensers

The turnkey approach for retubing condensers is a key competence within the Boiler Services Department. Specialized engineers in processing and mechanical construction work closely together with our service specialists. The Stork Thermeq Project Manager coordinates each project which – in general – consists of five different activities:

Condenser inspections

  • Visual inspection
  • Eddy Current tests
  • UT testing
  • Water quality determination


  • Process calculations
  • Analyzing the capacity and performance of the condenser according to the HEI-standard (= Heat Exchange Institute).
  • Alternatives for tube materials (e.g. titanium, stainless steel, copper alloys or other material) and dimensions
  • Calculating tube vibrations and tube supports
  • Optional calculations:
    • cooling water system
    • vacuum system
    • condensate system
    • dumptubes
  • Mechanical Engineering
  • CFD-simulations for analyzing mechanical conditions
  • Recalculating the spring supports
  • Detail drawings of condensers, tubesheets, inner steel and other mechanical parts

Tube expansion test

Before starting the retubing of the condenser, Stork Thermeq can perform a tube expansion test. During this test the rolled joints will be analyzed:

  • for strength of the rolled joints
  • for leakages: a leak test by PTT (Penetrant Test).
  • Condition of the expanded tube materials

Retubing condenser

  • Site preparation
    • Dismantling waterboxes
    • Calibration tests of instruments
    • Plan internal logistics
  • Removing existing tubes
    • Cut tubes inside condenser
    • Pull tubes from tubesheet
    • Disposal of tube material
  • Cleaning
    • Tubesheet preparation for expansion
    • Preparation of internal tube supports
    • Inside cleaning of the condenser
  • Assembly
    • Supply new tube materials
    • Install possible vibration correction solution
    • Place new tubes
    • Expand tubes in the tubesheet
    • Finishing tube ends
    • Clean the tubesheets and tubes
  • Leaktest
    • Testing the expanded tubes

Tube sheet protection by applying coating

  • Many condensor tubesheets are protected with a coating, such as Plastocor or similar. This coating material is applied in general overhauls and retubing projects.

Your benefits

  • Single point of contact: General project management as main contractor for engineering and service activities
  • Experienced in condensor retubing projects and applying alternative tube materials (e.g. titanium, stainless steel and copper alloys)
  • Turnkey approach: from inspections, engineering up to final tube leak tests