In vane pumps, slotted rotors splined to the drive shaft rotate between tightly fitted side plates inside oval or circular rings. The polished, hardened blades slide into and out of the rotor slots and follow a circular profile under the action of centrifugal force. An oil pumping cavity is formed between subsequent blades to transport oil from the inlet to the outlet. As the spacing between the blades increases, a partial vacuum is created at the entrance. As the size of the pump chamber decreases, the oil is squeezed out at the outlet.
Since the normal point of wear of a vane pump is the surface of the vane tip and the ring, the vanes and the ring are specially hardened and ground. Vane pumps are the only design with automatic wear compensation. As wear occurs, the blades only slide farther out of the rotor slots and continue to follow the contours of the ring. Therefore, the efficiency is always high throughout the life of the pump.
The displacement of a vane pump depends on the width of the ring and rotor and the stroke of the cam ring. The interchangeable ring design allows the basic pump to be converted into multiple displacements. Balanced design vane pumps are fixed displacement. Unbalanced designs can be built in fixed displacement or variable displacement pumps. Vane pumps have good efficiency and durability if used in clean systems with the right oil. They cover low to medium pressure, capacity and speed ranges. Relative to the output package size is small. Vane pumps are usually quiet but operate at high speeds.
1. Unbalanced vane pump. In an unbalanced design, the shape of the cam ring is a true circle, and its center line is different from the center line of the rotor. Pump displacement depends on the eccentric distance between the rotor and the ring. The advantage of a true ring is that you can apply controls to change the eccentricity and thus the displacement. The disadvantage is that the pressure imbalance at the outlet effectively resists a small area of the rotor’s edge, which places a lateral load on the shaft. Therefore, the size of the pump is limited unless very large earpieces and heavy supports are used.
2. Balance vane pump. In a balanced design, the pump has a fixed oval cam ring and two sets of internal ports. An extraction chamber is formed between any two blades twice per revolution. The two entrances and exits are 180 degrees apart. Back pressures at the rotor edges cancel each other out. Recent design improvements allow higher operating speeds and pressures, making this pump the most versatile pump in the field of mobile equipment.
3. Double pump. The vane double pump consists of two independent pump units. Each component is contained in its own housing and is mounted in series and driven by a common shaft. Each pump also has its own inlet and outlet, which can be combined using manifolds or pipes. Two designs are available, with both cartridges housed in one body. An additional pump is sometimes installed at the head end to provide auxiliary flow requirements.
Dual pumps can be used to provide fluid flow to two separate circuits or to combine the flow requirements of a single circuit. The delivery volume of the combined pump will not change the maximum rated pressure of any filter element. Separate circuits require separate pressure controls to limit the maximum pressure in each circuit.
Two pumps are used to provide fluid flow for fast forward and feed of the cylinder. In circuit B, two safety valves are used to control the operation of the pump. In circuit A, a safety valve and an unloading valve are used to control the pumping operation. In both circuits, the delivery of the pump core is merged after passing through the valve. This combined flow is directed to the four-way valve and the rest of the circuit.
In circuit B, when the cylinder rod reaches and trips the pilot valve, the upper safety valve is vented. The exhaust safety valve can freely guide the conveyance of the shaft end pump chamber back to the fuel tank. The maximum pressure of the other safety valve control circuit. The unloading valve and safety valve in circuit A perform the same operation. The outputs of the two pump boxes are combined to supply fluid for the fast forward portion of the cycle. When the output of one circuit is returned to the tank, after reaching a certain point in the cycle, the other circuit completes the advance part of the cycle. The outputs of the two pumps are then combined to return quickly.
4. Two-stage pump. The two-stage pump consists of two independent pump assemblies housed in a single housing. The pump assembly is connected so that fluid directed from the outlet of one pump to the inside of the other flows to the inlet of the other pump. Single inlets and outlets are used for system connections. Structurally, the pump consists of separate pump cores, which are driven by a common drive shaft contained in a housing. The diverter valve is used to balance the pressure load on each stage and correct minor flow differences from either spool.
In operation, the developer flow rate of each filter cartridge is the same as the developer flow rate of a single pump. Figure 3-13 shows the fluid flow in a vane two-stage pump. Oil from the oil storage tank enters the inlet of the pump and then flows to the outlet of the first stage pump box. (The channels in the pump body carry the emissions from this stage to the inlet of the second stage.) The outlet channels of the second stage direct oil to the outlet of the pump. Channel U connects the two chambers on the inlet side of the secondary pump and ensures that the pressure in both chambers is equal. (Pressure is the pressure applied to the pump from an external source.)
The diverter valve consists of sliding pistons A and B. The piston A receives an outlet pressure through the passage V. The piston B is subjected to pressure between the stages through the passage W. The piston responds to keep the pressure on the primary pump equal to half of the secondary pump outlet pressure. If the acceptable volume from the first stage exceeds the second stage, a pressure increase occurs in the channel W. The unbalanced force acting on the piston B moves the piston, so that excess oil flows through the channel B through the piston B to reach the piston B. Entrance chamber for the first filter cartridge. The fluid throttled by the piston B can maintain the pressure in the passage V.
If the discharge flow of the first-stage pump is smaller than the required flow of the second-stage pump, the pressure of the piston B will decrease. The unbalanced force acting on piston A causes the piston to move, causing oil to flow through piston A into channels X and W to replenish the second-stage pump and correct the imbalance. The channels Z and Y provide a means for leaking around the piston to return to the inlet chamber of the first stage pump. Pistons A and B always look for a position to distribute the load evenly between the two pump units.
Zhejiang Yongling Hydraulic Machine Co , Ltd . is a professional China manufacturer and supplier of Hydraulic Vane Pumps . Our products are widely used in cutting, plastic, forging, engineering, leather, pressure, metallurgy, agriculture, transportation machinery and machine tools, hydraulic stations, automatic production lines and other fields. Welcome to purchase: https://www.china-vanepump.com/
Since the normal point of wear of a vane pump is the surface of the vane tip and the ring, the vanes and the ring are specially hardened and ground. Vane pumps are the only design with automatic wear compensation. As wear occurs, the blades only slide farther out of the rotor slots and continue to follow the contours of the ring. Therefore, the efficiency is always high throughout the life of the pump.
The displacement of a vane pump depends on the width of the ring and rotor and the stroke of the cam ring. The interchangeable ring design allows the basic pump to be converted into multiple displacements. Balanced design vane pumps are fixed displacement. Unbalanced designs can be built in fixed displacement or variable displacement pumps. Vane pumps have good efficiency and durability if used in clean systems with the right oil. They cover low to medium pressure, capacity and speed ranges. Relative to the output package size is small. Vane pumps are usually quiet but operate at high speeds.
1. Unbalanced vane pump. In an unbalanced design, the shape of the cam ring is a true circle, and its center line is different from the center line of the rotor. Pump displacement depends on the eccentric distance between the rotor and the ring. The advantage of a true ring is that you can apply controls to change the eccentricity and thus the displacement. The disadvantage is that the pressure imbalance at the outlet effectively resists a small area of the rotor’s edge, which places a lateral load on the shaft. Therefore, the size of the pump is limited unless very large earpieces and heavy supports are used.
2. Balance vane pump. In a balanced design, the pump has a fixed oval cam ring and two sets of internal ports. An extraction chamber is formed between any two blades twice per revolution. The two entrances and exits are 180 degrees apart. Back pressures at the rotor edges cancel each other out. Recent design improvements allow higher operating speeds and pressures, making this pump the most versatile pump in the field of mobile equipment.
3. Double pump. The vane double pump consists of two independent pump units. Each component is contained in its own housing and is mounted in series and driven by a common shaft. Each pump also has its own inlet and outlet, which can be combined using manifolds or pipes. Two designs are available, with both cartridges housed in one body. An additional pump is sometimes installed at the head end to provide auxiliary flow requirements.
Dual pumps can be used to provide fluid flow to two separate circuits or to combine the flow requirements of a single circuit. The delivery volume of the combined pump will not change the maximum rated pressure of any filter element. Separate circuits require separate pressure controls to limit the maximum pressure in each circuit.
Two pumps are used to provide fluid flow for fast forward and feed of the cylinder. In circuit B, two safety valves are used to control the operation of the pump. In circuit A, a safety valve and an unloading valve are used to control the pumping operation. In both circuits, the delivery of the pump core is merged after passing through the valve. This combined flow is directed to the four-way valve and the rest of the circuit.
In circuit B, when the cylinder rod reaches and trips the pilot valve, the upper safety valve is vented. The exhaust safety valve can freely guide the conveyance of the shaft end pump chamber back to the fuel tank. The maximum pressure of the other safety valve control circuit. The unloading valve and safety valve in circuit A perform the same operation. The outputs of the two pump boxes are combined to supply fluid for the fast forward portion of the cycle. When the output of one circuit is returned to the tank, after reaching a certain point in the cycle, the other circuit completes the advance part of the cycle. The outputs of the two pumps are then combined to return quickly.
4. Two-stage pump. The two-stage pump consists of two independent pump assemblies housed in a single housing. The pump assembly is connected so that fluid directed from the outlet of one pump to the inside of the other flows to the inlet of the other pump. Single inlets and outlets are used for system connections. Structurally, the pump consists of separate pump cores, which are driven by a common drive shaft contained in a housing. The diverter valve is used to balance the pressure load on each stage and correct minor flow differences from either spool.
In operation, the developer flow rate of each filter cartridge is the same as the developer flow rate of a single pump. Figure 3-13 shows the fluid flow in a vane two-stage pump. Oil from the oil storage tank enters the inlet of the pump and then flows to the outlet of the first stage pump box. (The channels in the pump body carry the emissions from this stage to the inlet of the second stage.) The outlet channels of the second stage direct oil to the outlet of the pump. Channel U connects the two chambers on the inlet side of the secondary pump and ensures that the pressure in both chambers is equal. (Pressure is the pressure applied to the pump from an external source.)
The diverter valve consists of sliding pistons A and B. The piston A receives an outlet pressure through the passage V. The piston B is subjected to pressure between the stages through the passage W. The piston responds to keep the pressure on the primary pump equal to half of the secondary pump outlet pressure. If the acceptable volume from the first stage exceeds the second stage, a pressure increase occurs in the channel W. The unbalanced force acting on the piston B moves the piston, so that excess oil flows through the channel B through the piston B to reach the piston B. Entrance chamber for the first filter cartridge. The fluid throttled by the piston B can maintain the pressure in the passage V.
If the discharge flow of the first-stage pump is smaller than the required flow of the second-stage pump, the pressure of the piston B will decrease. The unbalanced force acting on piston A causes the piston to move, causing oil to flow through piston A into channels X and W to replenish the second-stage pump and correct the imbalance. The channels Z and Y provide a means for leaking around the piston to return to the inlet chamber of the first stage pump. Pistons A and B always look for a position to distribute the load evenly between the two pump units.
Zhejiang Yongling Hydraulic Machine Co , Ltd . is a professional China manufacturer and supplier of Hydraulic Vane Pumps . Our products are widely used in cutting, plastic, forging, engineering, leather, pressure, metallurgy, agriculture, transportation machinery and machine tools, hydraulic stations, automatic production lines and other fields. Welcome to purchase: https://www.china-vanepump.com/
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