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Cleaning and purging of pipes: Cleaning and purging are essential steps in the pipe installation process. The method of purging and cleaning depends on the pipeline design and the operational procedures. The conventional approach is as follows: First, clean water from a water tank is pumped into the pipeline system through fresh water pipelines to clean it, after which compressed air or steam is introduced into the pipes for air purging. The flow rate during water flushing should be no less than 1.5 m/s. The flow velocity V can be calculated using the following formula: Q: flow rate of the diesel/petrol pump, in m3/h; D: pipe diameter, in mm; V: flow velocity, in m/s. During water flushing, use a 1.5 Kg hammer to strike the dead corners of the pipe welds as well as the bottom of the pipe, but be careful not to cause any dents or imperfections on the pipe surface. 2 For the pipeline system after water flushing, visually inspect the color and transparency of the water at the outlet; it is considered qualified if they are consistent with those of the water at the inlet. 2 The pipeline system that has passed the flushing test should be restored to its original state promptly. 2 During flushing, the “Piping System Purging Record” should be filled out. 2 After the rinsing is successful, drain the water through the valve. Air purge 2: Close and open the relevant valves in the equipment and pipelines according to the layout of these pipelines. Generally, the valves connected to the equipment (large containers) are closed, while the valves in the pipelines are opened to connect the pipelines together into a system. 2 During air purging, the flow rate must be no less than 20 m/s. 2 During air purging, use a 1.5 kg hammer to strike the dead corners of the pipe welds and the bottom of the pipe. 2. Inspect for 5 minutes using a wooden target plate painted white at the outlet; it is considered qualified if there is no rust, dust, moisture, or other debris on the inner target plate. If it fails, it should be tested again. 2 Pipe systems that have been purged with air should be restored to their original state promptly. 2 Before cleaning and purging, unless otherwise specified in the technical drawings, it is also necessary to consider draining from higher points and collecting condensate from lower points; that is, additional drainage and condensate collection connections should be provided at the highest and lowest points in each pipe section, to facilitate drainage and condensate removal during cleaning and purging, as well as for purging the system before it starts operating.