Here you will find a few experiences and case studies describing inspection services carried out in Romania and Italy by AcousticEye's authorised service provider, Promment Services

1. Testing new Chinese tubes. Following a request by one of Romania's reputable manufacturers of pressure equipment, Promment Services' inspectors have tested a number of 812 Stainless Steel tubes, made in China. Although the products had all the required certificates (including Eddy current test certificates), the heat exchanger manufacturer wanted to perform and extra test. The inspection, which lasted one working day, has demonstrated that 94% of the tubes can be safely used, the remaining showing severe pitting (70% of wall thickness penetration), and one tube having a pore with a 0.534 mm dia. New, clean tubes help minimise errors, hence maximum precision has been achieved. However, due to the loose packing of the tubes, their numbering and preparation for testing took longer time than if they were already installed in the tubesheet.

2. Testing of heat exchangers inside an Italian hydrogen and nytrogen production facility. Carried out in 2012, this job consisted of testing 5 old heat exchangers, amounting to 2096 tubes, found in two production sites where nitrogen is delivered from, towards the largest Italian refineries. Although the working conditions seemed to be light, the tubes were made of stainless steel, and they showed signs of corrosion/erosion (possible manufacturing defects), but also small pores (0.45mm, 0.8 mm). Other aspects observed were an unusual concentration of defects, as well as the fact that the heat exchangers were not cleaned by the subcontractor to the client's standard.

3. Inspection of heat exchanger inside a petrochemical plant. There have been tested a total of 3265 unplugged tubes, out of which 74 showed holes, other 49 were extremely corroded, and a very large number showed severe blockages. After thorough analysis, many blockages were due to the tubes being plugged on the other end - and this observation determined the client to check if the tubes were actually plugged on both ends as they should have been. Extreme corrosion as well as deposits from the cooling water led to unusual high error rate, since pittings and pores were blocked by deposits - these errors can be however avoided by the usage of the new DUET™ technology. For this kind of application it is recommended to protect the tubesheet and the inside of the tubes with Duromar products, for a longer equipment lifespan.