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Corrosion Under Insulation (CUI) test rig

The test rig consists of a polycarbonate pipe with an OD of 52 mm and ID of 46 mm. A heating coil is located in the centre of the pipe and goes along its entire length, which ensures uniform heat distribution. The pipe is filled with heating oil to achieve homogeneous internal temperature. Corrosion rate is assessed by weight loss. Samples for weight loss consist of metal rings cut from actual pipe material. These samples are placed around the polycarbonate pipe, separated from each other using PTFE spacers. The rig also has a capability to determine the dry-out rate of the insulation in-situ by mean of electrochemical impedance spectroscopy. The extent of localized corrosion can be quantified by Alicona 3D surface profilometry.

Weather conditions in the field such as ambient temperature, %relative humidity can be simulated and controlled by an environmental chamber which can be programmed to simulate the fluctuation in temperature and %RH during day and night time.

Operational condition 
Pipe temperatureRoom temperature to 80°C
Environmental temperature20°C to 40°C
Relative humidity (%RH)40 to 80%
Schematic illustration of the CUI test rig housed in the environmental chamber
Schematic illustration of the CUI test rig housed in the environmental chamber
Close-up of CUI test rig with end caps simulating an enclosed system
Close-up of CUI test rig with end caps simulating an enclosed system