Pre-commission cleaning is an essential part of implementing any new pipework system, ensuring long-term performance and quality, as well as compliance with hygiene and safety standards.
In this article, we’ll explain what pre-commission cleaning of pipework systems entails and why it is important, and give an overview of the relevant standards.
Before piping systems are put into service, they often contain swarf (metal filings), leaves, scale, oil, grease, and leftover contaminants from the manufacturing, transportation, or installation process. They may also contain loosely adhered corrosion products, including rust particles and oxides. These impurities can contaminate the product being transported, increase the risk of corrosion on the pipe surface, and even restrict the flow of material through the pipework, lowering overall efficiency.
A thorough pre-commission cleaning procedure flushes out these unwanted materials, avoids blockages, improves corrosion resistance, and prepares metal surfaces for protective treatments. Pre-commission cleaning sets up your pipework to meet the operational standards and performance levels expected by your operation.
The Building Services Research and Information Association (BSRIA) provides a comprehensive set of best practices and guidelines (BG 29/2021 Sixth Edition) to ensure that new pipework systems are thoroughly cleaned and prepared before commissioning. These include detailed procedures for flushing, chemical cleaning, and treatment by biocides and inhibitors to remove any unwanted contaminants.
The flushing procedure usually involves filling the system with water which is then circulated at a relatively slow speed for a while to confirm there are no leaks. Then, proceed directly to the dynamic flushing stage.
This involves circulating water at high velocities to further dislodge and remove stubborn contaminant particles. Chemical cleaning may then be necessary to break down and remove deposits and scales, although, for sensitive pipework systems, water only should always be the first option, as it is the most ideal. However, if the pipework is contaminated, it will need chemical cleaning - no matter how sensitive. In this case, very careful selection with regard to chemistry and inhibitors will need to be made. It is advisable to contact a specialist to get this done.
This step is followed by another round of flushing to remove the chemicals and dissolved materials. As a final pre-commission stage, the system is often filled again with water treated with corrosion inhibitors, biocides etc to prepare it for operation.
Water flushing is generally effective for most systems, but varying pipe sizes can pose a challenge. Larger pipes require a higher velocity flush, while smaller pipes require less – requiring a balancing act between reduced velocity and increased water pressure. It’s important to plan your pre-commission cleaning carefully to consider these restraints within your system’s pressure limits.
Our Inox Passivation pre-commission cleaning service provides highly effective solutions for improved efficiency and environmental friendliness, as well as adhering to the latest BSRIA BG 29 standards. To find out more about our pre-commissioning services to request a quote, please send us a message by clicking here.
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