Industry News

Isuzu sewage suction trucks, also known as vacuum sewage suction trucks, are sanitation vehicles that use the principle of vacuum negative pressure to suck sewage. It's core component is the vacuum pump. There are generally two types of vacuum pumps used in sewage suction trucks:

1. Water ring vacuum pump:

The water ring vacuum pump (we refer to it as the water pump) is divided into an air inlet and an exhaust port, a stator and a rotor (impeller), and the air inlet is connected internally with the sewage suction tank. The impeller is eccentrically installed on the stator or casing, and the pump body is filled with an appropriate amount of water (antifreeze can be installed in winter) as the working medium liquid. When the impeller rotates, the water is thrown to the wall of the pump body under the action of centrifugal force, forming a closed rotating water ring with a shape similar to the pump body and nearly the same thickness. At this time, a crescent-shaped space is formed between the impeller and the water ring to form a vacuum.

And this space is divided by the impeller into several small cavities equal to the number of blades. During one working cycle of the impeller, the volume of the small cavities in the first half of the cycle increases from small to large, and is connected to the suction port on the end face (inside the sewage suction tank) The gas is sucked in; in the second half of the cycle, the small cavity changes from large to small, and the gas is compressed. When the small cavity is connected to the exhaust port, the gas is discharged out of the pump. With the rotation of the impeller, the suction and exhaust process proceeds continuously and stably, so the gas can be continuously sucked, forming a negative pressure state in the suction tank, so that through the suction tank at the end of the suction tank.

For example, the sewage is pumped into the sewage suction tank to achieve the purpose of sewage suction.

2. Rotary vane vacuum pump:

Rotary vane vacuum pumps are also called oil pumps. The principle of this pump is similar to that of a water ring vacuum pump. Both vacuums are formed by compressed air, but the working environment is completely different. Water ring vacuum pumps are cooled by liquid, while rotary vane vacuum pumps are cooled by air.

The rotary vane vacuum pump consists of an air inlet, an exhaust port, a rotor, and a rotary vane. The rotor is eccentrically fixed on the stator. There are grooves on the rotor for installing the rotary vane. The rotor can expand and contract radially according to the wall of the pump body cavity so that it can fit closely with the pump cavity. When force is applied, the eccentric rotor drives the rotary vane to slide close to the inner wall of the pump under the action of centrifugal force.

The volume of the suction working chamber gradually increases in the first half of the cycle, and the pumped gas is sucked into it until the rotary vane rotates to the end of suction. , as the space is continuously reduced, the inhaled gas is isolated; the rotor continues to rotate, the isolated gas is gradually compressed, and the pressure increases. When the pressure exceeds the pressure of the exhaust port, the gas is discharged out of the pump. This cycle is repeated to remove the air from the container to form a vacuum.