1515500013 Gear Pump Used In Concrete Pump Truck for Sany Zoomlion Xugong

1515500013 Gear Pump Used In Concrete Pump Truck for Sany Zoomlion Xugong

Product Description/Features:
  

Gear pump is a rotary pump that depends on the working volume change and movement formed between the pump cylinder and the meshing gear to transport liquid or pressurize it. Composed of two gears, the pump body and the front and back cover of two closed Spaces, when the gear rotates, the volume of the space on the side of the gear off from small to large, forming a vacuum, the liquid inhalation, the volume of the space on the gear meshing side from large to small, and the liquid squeezed into the pipeline. The suction cavity and the discharge cavity are separated by the meshing lines of the two gears. The pressure at the outlet of the gear pump depends entirely on the resistance at the pump outlet.

Structural characteristics
(1) Simple structure, cheap price;
(2) Low work requirements and wide application;
(3) The end cover and each tooth groove of the gear constitute a number of fixed sealed working cavities, which can only be used as a quantitative pump.

Gear adopts the international advanced level of new technology in the 1990s - double arc sine curve tooth arc. Compared with involute gear, the most prominent advantage is that the tooth profile surface does not slide relative during gear meshing, so the tooth surface has no wear, running balance, no trapped liquid phenomenon, low noise, long life and high efficiency. The pump gets rid of the shackles of traditional design, which makes the gear pump enter a new field in design, production and use.
The pump is equipped with a differential pressure safety valve as overload protection, and the total return pressure of the safety valve is 1.5 times the rated discharge pressure of the pump. It can also be adjusted in the allowable discharge pressure range according to actual needs. However, this safety valve can not be used for long-term work of the pressure reducing valve, and the pressure reducing valve can be installed separately when necessary.
The pump shaft end seal is designed in two forms, one is a mechanical seal, the other is a packing seal, which can be determined according to the specific use and user requirements.

Classification of pumps
As far as the core components are concerned, the gear pump is mainly composed of the common normal line gear pump and the circular arc gear pump. The common normal line gear pump is more durable than the circular arc gear pump, and the circular arc gear pump has a special structure, the transmission of clean media, low noise, long life, and each has its own advantages.
Working characteristics
Advantages: simple and compact structure, small size, light weight, good process, cheap price, strong self-suction, insensitive to oil pollution, large speed range, impact load resistance, easy maintenance, reliable work.
Disadvantages: radial force imbalance, large flow pulsation, loud noise, low efficiency, poor interchangeability of parts, not easy to repair after wear, can not be used as variable pump.

Oil trapping phenomenon
Reason: Hydraulic oil in the involute gear pump operation process, because the closed volume at the intersection of the gear changes with time, often a part of the hydraulic oil is sealed between the teeth, as shown in Figure 2, called trapped oil phenomenon, because the hydraulic oil is incompressible will make the external gear produce great vibration and noise, affecting the normal operation of the system.
Measures: The unloading groove is opened on the front and rear cover plates or floating sleeve, and the principle of setting the unloading groove is: the spacing between the two slots is the minimum closing volume, and the closing volume is communicated with the oil pressure chamber from the large to the small and the oil suction chamber from the small to the large.

Leakage phenomenon
The leakage of the gear pump is large, and the leakage path of the external meshing gear is the following three points: one is the top gap of the gear, followed by the measurement gap, and the third is the meshing gap.
Among them, the end-clearance leakage is large, accounting for 80%-85% of the total leakage, when the pressure increases, the former will not change, but the latter deflection increases, which is the main reason for the leakage of the external gear pump, the volume efficiency is low, so it is not suitable for use as a high pressure pump.
Solution: End clearance compensation adopts static pressure balance measures, adding a compensation part between the gear and cover plate, such as floating sleeve and floating side plate.

Force imbalance phenomenon
The right side is the oil pressure chamber, the left side is the oil suction chamber, the pressure of the two chambers is unbalanced; In addition, the pressure of the oil pressure chamber decreases due to the leakage of the tooth tip. Two unbalanced pressures act on the gear and shaft radial unbalance pressure, the higher the oil pressure, the greater the force, accelerate bearing wear, reduce bearing life, make the shaft bend, increase the tooth tip and shaft hole wear.

Prevention measures: Use pressure balancing tank or reduce the pressure oil chamber.
Seal form
1. Mechanical seal
2. Three layers with oil cavity seal
3. Single-layer seal
4. Magnetic seal Each sealing form needs to be determined according to different inlet pressure and sealing performance.

ABOUT COMPANY:

Changsha HuaYi Technology Co., LTD.,

Changsha HuaYi Technology Co., LTD., specialized in the sale of construction machinery parts.
Our company mainly business in various brands of pump trucks, excavators, cranes, wet spray machines and other accessories, as remote controls, Rexroth oil pump, transfer boxes, double pump pipes, lubrication pump, Harvey/Eaton/Parker/Kawasaki valves.
our company specializes in the offline and online trading of used construction vehicles in China, so the concrete pump trucks displayed on the website may have been sold offline.Our database provides a large number of fresh used concrete pump trucks, used excavator used mixer trucks and other construction vehicles, please contact our sales directly to provide you with more accurate services.Thank you for your patience to browse!​​