Hydraulic systems are essential components of many types of construction machinery, providing power and control for various functions. However, one common problem that can affect their performance and safety is leakage, which occurs when fluid escapes from unintended places in the system.

The first reason for hydraulic leakage is the size of hose fittings and connectors. If the diameter or thread size of the joints does not match the hydraulic hoses, or if the fittings are worn, the seal between them may weaken or break under pressure, causing fluid to leak. To avoid this, it is important to select and maintain the appropriate couplings and adapters and to inspect them regularly for signs of wear, corrosion, or misalignment.

The second reason for hydraulic leakage is surface leaks in hydraulic components, such as cylinders, pumps, and valves. These leaks can be caused by scratches, nicks, or pitting on the surface, as well as by loose or damaged seals. To prevent such leaks, it is important to keep the components in the hydraulic system of construction machinery clean and lubricated, to inspect them for surface damage, and to replace or repair any worn or defective seals.

The third reason for hydraulic leakage is leaks at the connection surfaces of hydraulic elements, such as pipes, fittings, and blocks. These leaks can be caused by insufficient or uneven tightening of the bolts or nuts, as well as by damaged or contaminated seals. To avoid such leaks, it is important to use proper torque values and sequences when installing and tightening the connections, and to use clean and compatible sealing materials.

The fourth reason for hydraulic leakage is sealing failures due to wear or poor sealing effectiveness. Seals are essential components of the hydraulic systems in construction machinery that provide a barrier between different fluids, pressures, or temperatures. When seals become worn, hardened, or contaminated, they may lose their ability to prevent leakage. To address this issue, it is important to choose high-quality seals that are suitable for specific operating conditions, to replace them periodically, and to avoid using incompatible fluids or applying excessive pressures.

The fifth reason for hydraulic leakage is the leakage between the valve spool and the valve body. Valves are critical components of hydraulic systems that regulate the flow and direction of fluid through various channels and pipes. A valve spool is a movable part that controls the opening and closing of the flow paths. If the spool or the valve body becomes worn or damaged, or if the spool clearance is too large, fluid may leak across the spool and into unintended areas. To minimize such leaks, it is important to maintain the valve components properly,  replace them if necessary, and adjust the clearance between the spool and body according to the manufacturer's specifications.

In conclusion, hydraulic leakage can be a common and frustrating problem for many construction machinery users. However, by understanding the possible reasons for leakage, and by adopting good practices and procedures for maintenance and inspection, we can reduce the occurrence and severity of leaks, and ensure the safe and efficient operation of the hydraulic systems in construction machinery.