What is the pollution control strategy for the fluid technology in the Niigata plunger pumps?

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As we all know, in hydraulic systems, the role of hydraulic oil is quite important. Therefore, some pumps, such as Nippon Precision plunger pumps, are equipped with advanced technologies for controlling contamination. So today, let’s take a look at how Nippon Precision plunger pumps manage contamination control of their hydraulic oil. The causes of fluid contamination are complex, and hydraulic fluid itself continuously generates contaminants; therefore, it is very difficult to completely resolve the issue of contamination in hydraulic fluids. To extend the lifespan of hydraulic components and ensure the reliable operation of hydraulic systems, it is a practical approach to keep the contamination level of the hydraulic fluid within certain limits. To reduce the contamination of hydraulic fluid, the following measures are often taken: (1) Clean the components and systems to remove contaminants remaining from the processing and assembly stages. NACHI hydraulic components should be purified after each processing step, and thoroughly cleaned after assembly. Before the system is assembled, the tank and pipes must be cleaned. Residues and surface oxides are removed mechanically, followed by acid washing. The system is thoroughly cleaned after assembly; it is best to use the oil used during operation of the system, and kerosene should not be used. During cleaning, everything must be sealed except for the fuel tank’s vent hole (which should have a dust cover). During cleaning, the flow rate should be increased as much as possible; if possible, hot oil flushing should be used. The viscosity of mechanical oil at 80°C is 1/8 of its viscosity at 25°C; therefore, thermomechanical oil at 80°C can remove many contaminants that mechanical oil at 25°C cannot remove. During flushing, the system must be equipped with a high-efficiency oil filter; at the same time, the components should be activated, and the welds and connection points should be struck with a copper hammer. (2) Prevent pollutants from entering from the outside. Hydraulic fluid can be contaminated by environmental pollutants during operation; therefore, an efficient air filter can be installed on the breather hole of the tank, or a sealed tank can be used to prevent the intrusion of dust, abrasives, and cooling agents. Hydraulic fluid can become contaminated during transportation and storage; the purchased fluid must be left to stand for several days before being poured into the system through a filter. Additionally, a dust seal should be installed at the end of the piston rod, and it should be checked regularly and replaced periodically. (3) Use an appropriate filter. This is an important method for controlling the contamination level of hydraulic oil; filters with different filtration precisions and structures should be selected based on the specific conditions of the system, and they need to be inspected and cleaned regularly. (4) Control the temperature of the hydraulic oil. Excessively high operating temperatures of hydraulic fluid are detrimental to hydraulic systems; moreover, the fluid itself accelerates its oxidation and degradation, resulting in various by-products that shorten its service life. The operating temperature of a general hydraulic system should ideally be kept below 65°C, and it should be even lower for machine tool hydraulic systems. (5) Regularly inspect and replace the hydraulic oil. At regular intervals, samples of the oil in the system are taken for analysis to determine whether its level of contamination remains within the acceptable range for use in that system. If it does not meet the requirements, it must be replaced immediately. It should not be replaced only when the oil is so dirty that it causes problems in the system’s operation. Before replacing the oil, the entire system must be cleaned first.