1.Condenser water pipe dead Angle
Any open cooling tower is essentially a large air purifier that can remove a variety of air pollutants. In addition to microorganisms, dirt, particles, and other foreign bodies, mild but highly oxygenated water also significantly improves corrosion activity. For this open system, due to the high chemical cost, the chemical treatment is always kept at a lower level, resulting in greater corrosion losses. In many cases, water filtration is inadequate, allowing any foreign particles that enter the system to stay there permanently. In addition, large amounts of iron oxide and other particulate matter gather together, creating many secondary corrosion problems in most open condenser water systems.
2. Double temperature piping system
Back in the 1950s, some private apartments, condominiums, and some office buildings featured a very common heating and cooling design, and these dual-temperature plumbing systems are now nearing the end of their useful lives across the country.
This elegant and simple heating and cooling design is typically used to supply hot or cold water to the window fan unit by placing thin-walled and small-diameter threaded 40-carbon steel tubes at the perimeter column supports. Some thermal insulation materials are usually thin-walled as 1-inch fiberglass, but are completely unsuitable for applications because it easily penetrates moisture and is always difficult to install into a proper area. The steel pipe itself has never been painted, coated or anti-corrosion protective layer, so that water can easily penetrate into the insulation layer and corrode the pipe from outside to inside.
3. Fire sprinkler inlet pipe
For all fire protection systems, the introduction of fresh water is the main cause of damage. Old pipe systems dating back to the 1920s and earlier are almost never drained for testing or any other purpose, but ultrasonic testing often finds these pipes still in near-new condition. In all fire protection systems, the most important area of corrosion is at the beginning of the system at the water source. Here, the natural flowing fresh urban water produces higher corrosion losses (often in stark contrast to the rest of the firefighting system).
4. Galvanized steel and brass valves
In almost all piping systems, galvanized steel pipe threaded directly to brass valves will cause some corrosion failures. Especially when galvanized steel is sandwiched between two brass valves, the damaging effects will be further amplified.
When the galvanized pipe is in contact with brass or copper metal, there will be a strong electric potential between the different metals and quickly destroy the surface of the zinc. In fact, the small current that flows between the two metals is similar to a zinc-based battery. Therefore, pitting is very serious in the immediate area of the connection, often affecting the already weakened thread to produce leaks or other failures.
Post time: Nov-16-2023