The efficiency of the hydraulic pump system depends on the volumetric efficiency of the hydraulic pump. When the volumetric efficiency drops to 72%, routine maintenance is required, such as replacing bearings and aging seals, and repairing the excess friction clearance or replacing accessories to restore its performance. Hydraulic pump maintenance method:
1. The oil supply form of the hydraulic pump is divided into two types: the straight axis swashplate pressure type and the sub pump plug force oil supply type, and the self suction oil type. Pressure supply pumps use a pressurized oil tank for hydraulic oil, and there are also hydraulic pump oil replenished by a built-in pump that provides pressure oil to the inlet of the hydraulic pump. The self priming ability of the pressure pump is very strong, and there is no need for external oil supply. If it is found that the hydraulic cylinder speed has decreased or is stuck, the hydraulic pump should be repaired by the vehicle. Check if there are any scratches on the edge of the impeller and if the clearance between the internal gear pump is too large. For self priming oil, the oil in the pump plug type pressure tank should not be lower than the lower limit of the oil level, which is sufficient to maintain the required quantity of hydraulic oil. The cleaner the hydraulic oil, the longer its service life.
2. The heaviest shaft of the plunger pump used in Hydraulic Pumps is the part that needs to be supported.
If there is clearance in the bearing, it cannot maintain the normal clearance of the three pairs of friction pairs in the internal pump pressure certificate. At the same time, it will also rub the damaged hydrostatic support oil film thickness of each pair, reducing the service life of the plunger used in the bearing pump. According to the information provided by the hydraulic pump manufacturer, the bearing is flat and has a service life of 10000 hours. If it exceeds this, it needs to be replaced with a new one. The removal and disassembly of bearings cannot detect clearance without professional testing instruments. Only visual inspection can be used. If any changes or scratches on the roller surface are found, they must be replaced. When replacing the bearing, pay attention to the English letters and models of the original bearings. The large bearing pump plug of the column adopts high load capacity bearings, and it is best to purchase products from the original manufacturer. If replacing with another brand, experienced personnel should check the table and exchange the bearing to ensure accurate bearing grade and load capacity.
3. Three pairs and inspection pairs for friction and repair
(1) The copper sleeve of the cylinder can be repaired by replacing the copper sleeve. First, trim the diameter of the first stopper rod to a uniform size, and then polish and sand the outer diameter of 1000 # or more
(2) The square composite body and copper sleeve of the melting cylinder.
(3) Mining process technology used in working face table
(4) Most of the copper material used for the casing of the cylinder body without material is ductile iron, and a thin film or coating is prepared on the non crystalline wall inside the cylinder body.
Due to the unique quality of the inner wall of the cylinder block hole, it is possible to form a hard hard friction blind effect. By grinding the cylinder bore, the inner wall of the cylinder bore is removed from the surface of the grinding material, resulting in better structural performance and improved wear resistance. If the friction pair is forcibly used, it will cause the temperature surface friction to increase, and the plunger rod will bond with the cylinder hole. In addition, a unique thin film coating is used on the surface of the column to prepare the rod plug. The coating contains a combination of wear reduction, wear resistance, and lubrication. The friction pair is actually a hard soft pair, and once the layer is changed, it will damage the best matching material of the friction pair. For this repair, special plunger pumps need to be sent to a professional repair shop.