How can I sweep the lines thoroughly?
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How can one clean the lines thoroughly? Generally, what is connected to the pipelines are pumps, heat exchangers, and containers. Some of these pipelines are very long, and the fluids flowing through them have high viscosity. What can be done to ensure thorough cleaning?
For regular cleaning, in multi-tube devices such as heat exchangers, it is necessary to use hoses or other pipes instead for cleaning, in order to prevent a large amount of debris from accumulating in the dead corners of the pipes in these devices during the cleaning process, which could lead to blockages. Or it may get clogged due to the small diameter of the internal pipes in these devices. Therefore, compressed air or steam is used for cleaning, and flexible hoses are employed to create a short circuit for cleaning the critical equipment. Because the equipment is processed after it has been manufactured. There is no need to participate in the line scanning.
More gas can be supplied. For multiple heat exchangers connected in series, they can be flushed one by one before all of them are opened for purging. Eliminate dead zones. Devices that do not allow scanning should be removed. Take a detour. Oils with high viscosity should be purged promptly before the temperature drops significantly. High-pressure steam should be used for long-distance pipelines. If cleaning in one direction doesn’t work, try blowing in the opposite direction.
In principle, the scanning should not pass over the equipment; to ensure thorough cleaning, it is necessary to stop and scan multiple times
During normal purging, the pipelines and equipment are disconnected, thereby reducing pipeline resistance and lowering the pressure required for purging. Nitrogen is suitable for purging; pay attention to the pressure on the pipes. Install a pressure gauge at the inlet of the pipeline to prevent it from bursting due to unexpected situations.
Let’s discuss it comprehensively: First, taking into account factors such as a large number of devices, long pipelines, and viscous media, the solutions are as follows: 1. It is best to use steam for purging all systems, especially those with viscous media, as the high temperature of steam helps to soften such media. 2. During purging, it is advisable to use the equipment’s bypass first, avoiding direct flow through the equipment; this prevents damage to the equipment’s sealing components. Generally, the purging pressure is much higher than the operating pressure. It must be cleared after blowing; otherwise, the equipment will get clogged. 3. If the pipeline is too long, it can be purged in sections; disconnect the flanges if necessary. Connect one section, link them together. 4. Be sure to empty it at each low level. 5. Purge for a longer period of time; half an hour to 3 hours is acceptable. After clearing the blockage, blow it out once more with compressed air. Remove moisture. 6. For larger equipment and pipelines, it is better to use compressed air; otherwise, the steam may not be able to pass through and will condense. 7. Finally, after the purging is complete, keep the air supply to the equipment open. Otherwise, it may cause negative pressure that flattens the pipelines and equipment.
The pipeline used for purging should not be too long; there should be a point where it can be disconnected, as purging in segments yields much better results. For media with high viscosity, a viscosity level that ensures similar solubility can be used; media with lower viscosity should be soaked or rinsed for 0.5–2 hours. After draining the medium from the pipeline equipment, it is purged using steam through intermittent blowing.
It is crucial to purge in a timely manner when the temperature of the material is high; of course, good heat tracing is also essential, as it becomes difficult to purge once the material’s temperature drops. For materials with high viscosity, it is effective to perform concentrated purging on a small portion first, followed by overall purging.
Generally, nitrogen is more commonly used for gas pipelines, as steam has a significant impact on subsequent production processes； For media with high viscosity, more steam is used ； Purging long pipelines is rather troublesome, as not all of them have points where they can be disconnected. It depends on what will be done after purging to decide on additional measures to take.
The equipment must be isolated, and the pipelines should be purged in sections
Maintain positive pressure – eliminate dead zones! ! Formulate strict suppression plans and strategies! ! !
The approach involves separating the pump’s inlet and outlet, filling the container with gas to a pressure of around 0.1–0.2 MPA, and then opening the inlet and outlet valves of the pump respectively to release the gas. This method yields good purging results; it is necessary to develop a specific purging plan based on one’s own process, but the purging must be carried out under pressure in order to achieve effective results
1. First, use steam or hot water to heat and cook the medium with high viscosity in order to reduce it. 2. Disconnect the flanges connecting the pipeline to devices such as pumps and heat exchangers, thereby separating the pipeline from those devices. 3. Use steam to purge the dirty pipelines separately. 4. Connect an external air source using a hose and carry out purging through blasting