The valve control system controls the flow by changing the opening of the valve throttle, thus controlling the speed of the actuator. Usually, the reason for low efficiency is the existence of throttling and overflow losses. Almost all mechanical equipment adopts valve control system. The pump control system can realize the stepless control of speed by changing the displacement of variable displacement pump, or control the flow through the combination of multiple constant displacement pumps to achieve the stepwise control of speed. The reason for high efficiency is that there is no throttling or overflow loss. It is widely used in high power hydraulic devices such as pressure processing machinery and plastic machinery. The actuator control system controls the flow by changing the variable hydraulic motor flow of the actuator, or through the joint work of multiple quantitative hydraulic motors, or by changing the action area of the composite hydraulic cylinder. Similar to the pump control system, this system has high efficiency because it has no throttling and overflow losses. It is suitable for traveling machinery, press and other hydraulic equipment.
The hydraulic motor has two circuits: the hydraulic motor series circuit and the hydraulic motor braking circuit. These two circuits can be classified into the next category. One of the series circuits of hydraulic motors: three hydraulic motors are connected in series with each other, and a reversing valve is used to control the start stop and steering. The flow through the three motors is basically the same. When the displacement is the same, the speed of each motor is basically the same. The oil supply pressure of the hydraulic pump Xuchang Manufacturer High, small pump flow, generally used for light load and high speed. Serial circuit II of hydraulic motor: each reversing valve in this circuit controls one motor, each motor can work independently or simultaneously, and the rotation direction of each motor is also special-purpose orbit motor optional. The oil supply pressure of the hydraulic pump is the sum of the working pressure difference of each motor, which is applicable to the condition of high speed and small torque.
After disassembling and inspecting the hydraulic motor installed on the drill, it was found that the friction surface of the valve disc and the port plate of the hydraulic motor was severely worn, and the deepest worn part was 0. 15mm; The output shaft oil seal is leaking. Cause analysis of oil leakage of output shaft oil seal. After disassembly inspection and test, the axial and radial clearances of the output shaft meet the standard requirements special-purpose orbit motor There is no obvious wear on the oil seal mating surface. However, it is found that the oil seal rubber has hardened and its elasticity has deteriorated. With the increase of sealing lip wear, the pre tightening capacity and sealing performance decrease, and the excessive oil temperature accelerates the wear of sealing lip; In addition, due to the liquid Xuchang orbit motor The leakage of the pressure motor causes the back pressure in the housing to be too high, which further aggravates the wear and leakage of the sealing lip. The smaller the friction of the rotor in the stator sleeve, the higher the mechanical efficiency of the motor.
System for fixed equipment. This hydraulic system is mostly an open cycle system, including machine tools (workpiece clamping, worktable feeding, direction exchange, spindle drive), presses (pressing, blank holder, direction exchange, workpiece ejection), die-casting machines and injection molding machines (mold closing, demoulding, preforming, injection mechanisms), medical devices, garbage compression and other mechanical devices Xuchang special-purpose System of standby and working devices. The hydraulic system for traveling equipment includes both open circulation system and closed circulation system, including vehicle driving (traveling drive, steering, braking and working equipment orbit motor Manufacturer ), material conveying, loading, unloading and conveying equipment (conveying mechanism, transposition mechanism), various systems of aviation, space and navigation engineering.
If the hydraulic system is compared to the human body, then the hydraulic oil is equal to human blood. In the hydraulic system, the hydraulic oil plays a role in energy transmission, system lubrication, and prevention Xuchang orbit motor The functions of corrosion, rust prevention and cooling, and whether the hydraulic system can work effectively are closely related to the type and selection of hydraulic oil. Coding, composition and characteristics of hydraulic system: high purity general machine tool oil, refined mineral lubricating oil, with good rust resistance and oxidation resistance. High wear resistant hydraulic oil, refined mineral lubricating oil, rust proof, anti-oxidation, anti-wear. High temperature and high pressure hydraulic oil, with the characteristics of rust prevention, oxidation resistance, wear resistance, etc., is refined into mining lubricating oil, and added with viscosifier. Refined mining lubricating oil HG hydraulic guide oil, rust proof, anti-oxidation, anti-wear, anti stick slip. HS synthesis special-purpose orbit motor Hydrocarbon is a kind of low temperature hydraulic oil, which has the characteristics of anti-oxidation and anti-wear.
What is the oil supply mode of the hydraulic pump? The straight shaft swashplate plunger pump can be divided into two types: self suction type and pressurized type. Most high-pressure oil supply hydraulic pumps use pneumatic oil tank, and some hydraulic pumps are also equipped with oil make-up slave pump to deliver pressure oil to the oil inlet of the hydraulic pump. The self-priming pump has the characteristics of strong self-priming ability and no need for external oil supply special-purpose orbit motor 。 Bearings for hydraulic pumps. The most important part of the plunger pump is the bearing. If the bearing has clearance, the normal clearance of the three pairs of friction pairs inside the hydraulic pump cannot be guaranteed. At the same time, the hydrostatic support oil film thickness of each friction pair will be damaged, thus reducing the service life of the plunger pump bearing. According to the data provided by the manufacturer of the hydraulic pump, the average service life of the bearing is 10000 hours. If the service life exceeds this value, a new port shall be replaced. 3、 Conclusion. The service life of the piston pump is related to the maintenance at ordinary times, the quantity and quality of the hydraulic oil, and the cleanliness of the oil. At the same time, avoid orbit motor Manufacturer The particles in the oil will wear the friction pair of the plunger pump, which is also an effective method to extend its service life.
