Hastelloy loops

The two Hastelloy loops are used for high temperature and high pressure corrosion testing.

Nyborg, Rolf




  • CO2 and H2S corrosion testing at high temperature
  • experiments with high salt concentration
  • corrosion inhibitor testing
  • testing of production chemicals

The Hastelloy loop consists of the following instrumentation:

  • potensiostat (2x8 channels) for LPR, AC impedance and sweep measurements
  • pH monitoring system
  • O2 monitoring equipment
  • computerised data aquisition system

Technical specifications
Loop material: Hastelloy C-275
Single phase: Water Pressure: max. 50 bar
Temperature range: 10-180 °C
Flowrange: 0-10 m/s
Test sections: 3
Specimens: Up to 36
ID test section: 25 mm
Volume: 75 l


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The loop system consists of a main circulation circuit with low flow autoclaves and a pressuriser coupled in bypass. The ID of the main circuit is 25 mm. A centrifugal pump with canneled motor is used to circulate the water. Several autoclaves are linked to the loop where corosion products or scale can be precipitated out or dissolved in order to control the composition of the water phase. It is also possible to renew a small part of the loop water continuously. One of the autoclaves can be filled with oil in order to keep the water phase in contact with an oil phase when inhibitors are tested.

The loop is equipped with three horizontal test sections which can be bypassed and operated independently. One of the test sections can be periodically exposed to stagnant, dry or oil wet conditions in order to study variation in operational parameters. The test sections can accomodate both flat and flush mounted tubular specimens, twelve in each specimen rack.

The first four specimens in the row are electrically wired and used for electrochemical measurements. The loop is equipped with two eight-channel potenstiostats for electrochemical corrosion measurements and a radioactive corrosion monitoring system.