Repair process of piston rod of Manifold Block hydraulic cylinder
Repair processing technology of piston rod of Manifold Block hydraulic cylinder:
(1) The first part of the welding will be clean and tidy, and then with wet soil around the pull marks.
(2) Choose the electrode with a diameter of 2.5mm, adjust the current value of the DC welding machine to 120A, and choose the linear strip method for steady welding.
(3) After all welding, the soil and slag will be eliminated and clean, and the rough file will be carried out along the hydraulic cylinder circle and the feed amount of 0.1-0.2mm will be left.
(4) A cylinder with a diameter of 185mm, an outer diameter of 125mm and a length of 150mm should be cut by the mold (hydraulic cylinder diameter of 125mm), and sawed along the axis. One is a rough mold and the other is a fine mold.
(5) The inner wall of the rough die is coated with a thin layer of red printing oil, and then the rough die is close to the repair part of the hydraulic cylinder along the axis to run in for several times, and then the impressions on the hydraulic cylinder are filed away with a fine file. The file is constantly trimmed, leaving a feed of 0.04-0.07mm.
(6) Then use the 320 purpose sand bar dipped in gasoline to cooperate with the fine mold to grind the hydraulic cylinder to the required specifications.
(7) Finally, the back of the sandpaper is dipped in the car with gasoline for manual polishing treatment. After accurate measurement, the large error is only 0.03mm
The temperature rise problem of electromagnet when the solenoid reversing hydraulic valve is working
The design and manufacture of the solenoid of Manifold Block electromagnetic directional hydraulic valve adopt H-grade heat resistance grade, so the temperature rise in normal operation does not need to worry about the service life of the solenoid. The temperature rise of the dc electromagnet: the only reason for the temperature rise of the DC electromagnet is the coil temperature rise caused by copper damage. The degree depends on current density and heat dissipation.
Manifold Block electromagnetic directional hydraulic valve
In general, the temperature rise of dc electromagnet is less than that of AC electromagnet. The temperature rise of the AC electromagnet is caused by the loss of copper and iron, depending on the following points:
1. Loss caused by short circuit ring.
2. Loss caused by cyclic power supply between laminated rivets.
3. Core eddy current loss and hysteresis loss.
4, the excitation internal resistance causes the coil resistance loss. In addition, it is related to the operating frequency. The higher the frequency, the longer the time in the starting current, and the higher the temperature rise will be.
Finally, when the electromagnetic directional valve due to external force caused the spool can not move, electromagnet can not be energized to the armature adsorption to the normal position, magnetic path blocked, coil temperature will rise sharply, especially for AC electromagnet, easy to cause the coil burned in a short time. Therefore, attention should be paid to the cleanliness of the hydraulic system in use to avoid electromagnetic reversing valve failure and extend the service life.
Manifold Block hydraulic solenoid valve has three common faults
The failure of Manifold Block hydraulic solenoid valve will directly affect the operation of the reversing valve and regulating valve. The common faults include the failure of the solenoid valve, which should be investigated from the following aspects:
1. Manifold Block hydraulic solenoid valve is stuck: the mating clearance between the solenoid valve slide sleeve and the valve core is very small (less than 0.008mm). Generally, it is a single assembly, and it is easy to get stuck when there are mechanical impurities or too little lubricating oil. The processing method can be used to poke steel wire through the hole of the head to make it bounce back. The fundamental solution is to remove the solenoid valve, take out the spool and the spool sleeve, clean with special cleaning agent, so that the spool is flexible in the valve sleeve. When disassembling, attention should be paid to the assembly sequence and external wiring position of each component, so that the reassembly and wiring are correct, but also to check whether the oil spray hole of the oil mist is blocked, whether the oil is enough.
2, the wiring head of Manifold Block hydraulic solenoid valve is loose or the wire head falls off, the hydraulic solenoid valve is not electric, and the wire head can be tightened; 4, leakage: leakage will cause insufficient air pressure, making the opening and closing of the forced valve difficult, the reason is that the sealing gasket damage or slide valve wear caused by several cavity channeling. When dealing with the solenoid valve failure of the switching system, the appropriate time should be selected, such as the solenoid valve is in the loss of power to deal with, if in a switching clearance processing can not be finished, the switching system can be suspended, calmly deal with.
3. The coil of Manifold Block hydraulic solenoid valve is burnt out, and the wiring of the hydraulic solenoid valve can be removed and measured with a multimeter. If open, the coil of the solenoid valve is burnt out. The reason is that the coil is damp, causing poor insulation and magnetic leakage, causing the coil current is too large and burned, so to prevent rain into the solenoid valve. In addition, the spring is too hard, the reaction force is too large, the number of turns of the coil is too small, and the suction is not enough to burn the coil.