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Purchasing Better News

• Preface

A large financial property has the interest to return an abandoned condenser water line back into service.  Since the pipe is 40 years old and has been idle for at least 10 years, an interest is raised to first chemically clean the pipe.  A chemical treatment company is awarded the contract for the cleaning service followed by maintaining the chemical treatment, and recommends a preliminary ultrasonic evaluation of the piping for potential weakness given plans to use an inhibited yet strong acid cleaner.

• Investigation

The building manager delays its approval for the ultrasonic testing for weeks and does not provide the approval for the work until the day that chemical cleaning is scheduled.  Beginning at the larger diameter piping, CorrView International, LLC finds moderate corrosion and deep pitting but still more than sufficient wall thickness to safely complete the planned cleaning to be performed overnight.  Under the assumption that the rust deposits will be removed and an effective chemical treatment program installed, very long service life exceeding 50 years can be predicted for the larger risers.

Further testing is directed to the smaller threaded steel distribution piping which separates in direction and runs through various computer rooms.  Here we measure noticeably higher corrosion activity with deep and severe pitting.  High under deposit pitting is suspected due to the accumulation and settlement of iron oxide as a result of the moderate corrosion measured at the larger main lines.  Wall thickness measurements are near or below minimum standards, with some examples dangerously close to the limit of the thread cut.  Investigation identifies some wall thickness measurements down to near 0.085 in., and at 2 in. pipe having an outer thread cut of 0.072 in.  At the same time such findings are realized, personnel from the chemical treatment company are setting up their pumps and tanks for the cleaning process to run overnight.

Completing the ultrasonic survey at 6PM, a phone call to the chemical company warns their president not to chemically clean the pipe, and cites the low wall thickness measurements found at the smaller diameter threaded pipe within active computer rooms.  Our recommendation is for the building to remove all smaller threaded distribution pipe for replacement with new schedule 80 or copper pipe, and utilize that time to chemically clean just the main risers, which are heavy enough to handle any proposed chemical cleaning.

Although a strict deadline has been expressed by the building management to the chemical treatment company president to complete the chemical cleaning on that date, he cancels the procedure and withdraws the service personnel.  Notice of this event infuriates the building management client who cancels all further projects with the chemical treatment company and hires a new firm to perform the work.

The new firm plans to chemically clean the pipe in the next few days using a similar procedure, and brings onboard an ultrasonic investigator to assess the condition of the pipe.  Although directed to very specific areas of the computer room distribution lines where CorrView had documented severe weakness of the pipe, and had even marked the pipe where such low wall thickness was identified, the new UT company finds no concerns and certifies the pipe as safe for chemical cleaning.

• Conclusion

Chemical cleaning is performed the next night, and causes a total pipe separation at ceiling located condenser water pipe of 2 in. diameter.  Water produces extensive damage to the computer rooms and lower floors.

© Copyright 2024 – William P. Duncan, CorrView International, LLC