What Is The Hydraulic Coolers?
The hydraulic coolers in the hydraulic system play a vital role. Its main function is to reduce the temperature of the hydraulic oil, to ensure the normal operation of the system, and extend the service life of the equipment. In this article, we will introduce the hydraulic cooler operating procedures, precautions, cleaning methods and common troubleshooting methods.
How To Use The Hydraulic Clooers
Before starting the hydraulic cooler, the following checks and operating procedures must be performed:
Check Attachments And Gauges
Before starting, all attachments and gauges must be carefully inspected to ensure that connections are tight and free of looseness. This is to prevent leakage and equipment damage due to poor connections during startup.
Oil Drain Preparation
Unscrew the screw plug that is outside the cooler’s oil outlet. And then slowly open the oil inlet valve (at this time the oil drain valve is closed). When the oil overflows, close the inlet valve and tighten the screw plug. The purpose of this step is to remove air from the system. And ensure that the hydraulic oil can enter the cooler smoothly.
Venting Preparation
Unscrew the air vent valve in the cooler line and slowly open the water inlet valve (the drain valve is closed at this time). When the water is full, close the water inlet valve and exhaust valve. At this time the water and oil are static, the temperature difference gradually become smaller. The purpose of this step is to ensure that the cooling water is full of cooler, and eliminate the air in the system.
Start Operation
When the water temperature rises 5-10 ℃, open the cooling water and oil discharge valve. And then gradually open the cooling water and oil into the valve, so that both are in the flow state. Then adjust the flow rate of the cooling water to keep the temperature of the oil out in normal working condition. This step ensures effective heat exchange between cooling water and hydraulic oil in the cooler. This can maintain the normal operating temperature of the system.+
Stop Operation
When the cooler stops operation due to malfunction or normal. The operation procedure is to close the oil and cooling water inlet valve first. Then close the oil and cooling water discharge valve. And finally unscrew the screw plugs on the drain and oil drain ports to drain the cooling water and oil from the cooler. This procedure ensures that there is no residual liquid inside the cooler when it stops working and prevents corrosion and icing.
Precaution Of The Hydraulic Coolers
When starting the cooler, avoid rapidly opening the inlet valve to prevent a poorly conductive “subcooling layer” from forming on the heat exchange tube surfaces due to excessive coolant flow through the cooler. This layer significantly impairs cooling efficiency, even with ample water volume.
To prevent electrochemical corrosion in the water side, install a zinc rod at specified points in the inlet and outlet covers. The zinc rod effectively counters electrochemical effects in the coolant, extending the cooler’s lifespan. Purified fresh water should be used as coolant.
If river water is used, ensure a filter is installed at the inlet to prevent impurities and microorganisms, reducing tube blockage and corrosion. Maintain lower coolant temperatures and higher flow rates to enhance heat exchange and prevent scale formation on tube surfaces.
Ensure that oil-side pressure in the cooler exceeds water-side pressure to prevent coolant infiltration into the hydraulic oil, maintaining system cleanliness. In cold seasons when the cooler is inactive, drain water completely to prevent freezing and subsequent expansion that could damage the cooler.
How To Clean The Hydraulic Coolers?
During prolonged operation, the hydraulic cooler accumulates deposits on the inner walls of its pipes, leading to decreased heat exchange efficiency and suboptimal cooling performance. Depending on water quality, it is recommended to conduct internal inspections and cleanings every 5-10 months.
The cleaning process involves the following methods: On the water side, use a hose to high-speed flush the front and rear covers, as well as the inner surfaces of the heat exchange tubes. While brushing with cleaning tools, followed by drying with compressed air. This high-speed flushing and brushing effectively remove dirt and scale from both the inner and outer surfaces of the heat exchange tubes. This can ensure continued efficient heat exchange.
On the oil side, employ solvent flushing methods: Use trichloroethylene solution circulated within the cooler. To maintain a pressure not exceeding 0.6 MPa, preferably against the flow direction of the hydraulic oil. The duration of flushing depends on the extent of contamination. Afterward, flush with clean water until the effluent is clear. Trichloroethylene solution effectively dissolves oil-side deposits and carbon buildup, preserving the cleanliness of the heat exchange tubes.
Alternatively, immerse the cooler in a soaking solution for 15-20 minutes, checking the solution color. Replace with fresh solution if corrosion is evident, soaking until clean, followed by thorough rinsing with clean water. (When using carbon tetrachloride for cleaning, ensure proper ventilation to avoid toxicity.) The soaking method provides a more thorough removal of deposits and carbon buildup from within the heat exchange tubes, ensuring effective cleaning.
Conduct pressure tests post-cleaning using either hydraulic or 0.7 MPa pneumatic tests to verify the cooler’s seal integrity and strength before reinstalling it into the system, thereby ensuring its reliable operation.
Maintenance Guidelines And Machine Warranty
To maintain optimal performance of hydraulic coolers. The regular cleaning every 5-10 months is essential to prevent reduced heat exchange efficiency from internal deposits, tailored to water quality. Cleaning involves high-speed flushing of covers and tubes with clean water and brushing, followed by air drying.
For effective oil-side cleaning, use trichloroethylene solution followed by water flushing or immersion in a cleaning solution. Post-cleaning, perform pressure tests to verify seal integrity. Our commitment to quality includes a comprehensive one-year warranty for the entire machine, ensuring reliable performance and customer satisfaction.
