How To Maintain Shell And Tube Air Compressor Coolers?
How to Maintain Shell and Tube Air Compressor Coolers?
Regular Cleaning
External cleaning
Periodically (once a month is recommended) clean the surface of the cooler housing of dust, oil and other debris. This can be done by wiping with a clean rag or soft bristle brush. This is because the accumulation of dust and other debris can affect the cooling efficiency of the cooler, resulting in a decrease in cooling effect.
For oil stains that are difficult to clean, a mild detergent can be used for cleaning, but care should be taken to avoid the detergent getting inside the cooler.
Internal cleaning (for inside of tubes)
When a decrease in cooling efficiency is noticed or depending on the time of use (e.g. every 1 - 2 years, depending on the environment and frequency of use), the inside of the tubes need to be cleaned. This is because minerals and impurities in the cooling water can form scale or dirt inside the tubes, affecting the heat exchange efficiency.
Chemical cleaning is one of the commonly used methods. Specialised acidic or alkaline cleaning agents can be used, which are formulated according to the instructions. For example, for calcium carbonate scale, you can use an appropriate amount of hydrochloric acid solution for cleaning, but the concentration and cleaning time should be strictly controlled to avoid corrosion of the tube.
Physical cleaning can use high-pressure water flushing or mechanical cleaning tools. High-pressure water flushing, pay attention to the pressure can not be too high, so as not to damage the tube. Mechanical cleaning tools such as soft brushes or scraping tools can be used to scrape the inside of the tube to remove the adhering dirt.
Checking for leaks
Daily inspection
Check the cooler for signs of leakage before each start-up or at regular intervals (weekly is recommended). Check areas such as tube plates, tube to tube plate connections, weld seams in the housing, and inlet and outlet connections. This is because leaks can lead to leakage of cooling medium (e.g. water) or compressed air, affecting the cooling effect and system pressure.
Observe the ground around the cooler for liquid (in the case of a water cooling system) or hear unusual airflow sounds, which may signal a leak.
Pressure Tests
Perform a pressure test at regular intervals (e.g., once a year). Isolate the cooler from the air compressor system, fill the inside of the cooler with nitrogen or other inert gas at a certain pressure (usually 1.1 - 1.25 times the design pressure), and apply a soapy water solution to the area of possible leakage. If bubbles form, a leak exists.
Inspection and maintenance of the support structure
Periodic inspection of support components
Inspect the cooler's support legs, brackets and hangers, and other components every six months. Look for looseness, deformation or corrosion of these parts. This is because damage to the support structure may cause the cooler to shift out of position, causing uneven stress on the piping connections and triggering problems such as leaks.
For the loose bolts and other connecting parts, tighten them in time; for the corroded and serious support parts, replace them in time.
Ensure levelness and perpendicularity
Regularly (once a year is recommended) check the level and verticality of the cooler. Measurements can be made using a tool such as a level. If the cooler is not installed horizontally or vertically, it will affect the flow of cooling medium and compressed air inside and reduce cooling efficiency.
Monitoring of operating parameters
Temperature monitoring
Temperature sensors are installed at the inlet and outlet of the cooler to monitor the temperature of the compressed air and cooling medium in real time. Under normal circumstances, the temperature of compressed air should be reduced to within the design range after cooling. If the temperature difference between the inlet and outlet is found to become smaller, it may be that the cooler is internally scaled or clogged, and needs to be inspected and dealt with in time.
Pressure Monitoring
Similarly, pressure sensors are installed at the inlet and outlet to monitor the pressure of the cooling medium and compressed air. Abnormal changes in pressure may indicate clogging or leakage inside the cooler. For example, a drop in pressure on the cooling medium side may be due to a leak in the pipework or a blockage causing a reduction in flow.
Check ancillary equipment
Check valves and pipework
Periodically (quarterly is recommended) check that the valves connected to the cooler open and close properly and that there are no leaks. Check piping for deformation, corrosion or blockage.
For valves, check the flexibility and sealing performance of the valve stems; for piping, look for any damage to its appearance and any accumulation of foreign matter inside.
Check the circulating pump (in case of water cooling system)
Check the operating status of the circulating pump, including whether the pump pressure, flow rate, motor current and other parameters are normal. Check the sealing condition of the pump once a month to prevent coolant leakage.
Regularly (e.g., every six months) perform maintenance on the circulating pump, such as replacing the lubricating oil and checking the wear and tear of the impeller.
