Suction truck related knowledge summary

According to the use of features are divided into: Self-absorption self-discharge suction truck, dump truck, suction fecal sprinkler, agricultural suction truck

Third, the composition of suction truck

Suction vehicles are mainly composed of: tanks, vacuum pumps, power take-off devices, four-way valves, water and gas separators, oil and gas separators, return tanks, booms, and locking mechanisms.

1 tank  

The tank body is the main body of the feces vehicle. The top of the tank body is provided with an air hole and a suction hole. The air hole communicates with the air-gas separator and is the passage for the air into and out of the tank body. Into the hole usually sealed when maintenance can be opened, the suction hole on the suction pipe under suction with siphon manure channel into the tank body.  

There are walk-in boxes at the middle of the two sides of the tank, which are usually used for shelving suction hoses and stand when repaired. The interior of the tank body is equipped with an anti-sloshing plate to reduce the damage caused by the violent sloshing shock of the liquid caused by the driving of the vehicle and the joint of the tank body and the frame thereof. The front head is equipped with an observation tube to monitor the load and prevent overloading. There is a cleaning hole at the bottom, which is normally sealed. When cleaning the tank, the cleaning hole cover can be opened to allow the sewage to drain.  

The tank body is rigidly connected and is mounted on the frame. There is a cushion in the middle to reduce the damage of the vibration of the vehicle to the tank body.  

Since the suction hose is always immersed on the liquid surface, the air in the tank body is sucked and becomes thinner as it is not supplemented, so that the pressure in the tank is lower than the atmospheric pressure, and the waste liquid is under the action of the compressed air. , Drain the tank by suction pipe.  

2, vacuum pump  

Suction truck vacuum pump is a key component of the suction truck. It mainly cooperates with the power take-off device, the three-way four-position valve, etc. to achieve vacuum and pressurize the tank.

At present, the commonly used suction truck is a single-stage rotary oil seal vacuum pump, the ideal working pressure is 200PA--8500PA, with convenient installation, high vacuum, high efficiency.
The vacuum pump is mainly composed of a pump body, a rotor and its assembly, a pump casing, a rotary vane, a slip ring, a bearing cap and a sealing device. The rotor is a wearing part. In order to facilitate disassembly and repair, the rotor turning center deviates from the center of the pump body.

Its working principle is that the eccentric rotor is driven by the power take-off device and the tank is sucked into the compression chamber. When the pressure exceeds the specified value of the exhaust port, the compression chamber is automatically opened and the compressed air is discharged, so that the internal air of the tank is drawn out. Repeatedly circulating, a vacuum forms inside the tank.

In order to ensure the normal operation of the vacuum pump and avoid contamination, an oil-gas separator and a water-gas separator are also installed in the production of the suction truck to filter the water vapor and oil and gas in the compressed gas.

3, power take off  

Suction truck vacuum pump operation is to rely on the engine power through the power take-off, the drive shaft to rotate, the power take-off is installed in the right side of the transmission, the upper part of the operating handle is located in the middle board of the cab.  

The power take-off consists of an input gear, an input shaft, an intermediate gear, an intermediate shaft, an output shaft, an output gear, a fork shaft, a fork, and a handle.  

The input gear and transmission output gear are constant mesh pairs. Before starting the vacuum pump, the transmission output gear is a constant mesh pair. Before starting the vacuum pump, the transmission is engaged in neutral, then the engine is started, the clutch is disengaged, the power takeoff switch is opened, the fork shaft is moved forward, and the fork drives the output gear on the output shaft, sliding and meshing with the middle gear. The output shaft is transmitted by spline and output gear to the input gear, and the intermediate gear is transmitted to the output gear, which is transmitted to the transmission shaft by the output coupling. This drives the vacuum pump to rotate.  

4, four-way valve  

The vacuum pump can only rotate counterclockwise (facing the front). To take in air from the tank or to discharge air into the tank, a four-way valve is required.  

The four-way valve communicates with the tank, vacuum pump and return tank. The four-way valve has a partition. Change the suction direction of the vacuum pump. When the four-way valve connects the holding tank with the vacuum pump, the dropping truck will perform the discharge operation.  

5, water and gas separator  

The water-gas separator is located at the top of the front of the tank and the rear tank. Its interior has a gas pipe with rectangular holes on both sides of the pipe for air into and out of the tank. During the suction operation, the air in the holding tank comes out of the rectangular hole, the volume suddenly increases, the flow velocity decreases, and the number of heavy water molecules decreases, which can reduce the damage to the lubricating oil and the mechanical parts.  

6, oil and gas separator  

The compressed air discharged from the vacuum pump has a high speed, and when it breaks through the oil film layer, it carries a large amount of oil droplets. In order to reduce fuel consumption and prevent pollution, an oil-air separator is installed. Separation of oil and gas is located in the right middle of the frame of the feces truck, preceded by a vacuum pump, and then returned to the tank. The oil and gas separation is provided with oil retaining pipes. When the compressed air enters, its volume suddenly expands, the flow velocity decreases, and the flow direction changes, and flows out through the porous oil retaining pipe. As the flow velocity of oil and gas molecules decreases, the impact on the wall of the wall and the hole wall intensifies, and the heavy oil molecules are partially attached. On the wall, the condensed oil drops, the wall of the distributor and the overflow pipe flow back to the tank, and the compressed air after the initial purification flows to the upper tank.  

7, return tank  

The return tank is located in the middle of the right side of the frame, with left and right air separators and four-way valves on the right.  

There is an oil retaining net in the return tank, and the inlet and outlet are not connected. The compressed air flowing from the oil separator must pass multiple obstacles before it can be discharged to the four-way valve. Since the volume of the return tank suddenly increases exponentially, the air flow rate is obviously increased. Reduced, combined with barriers such as oil screens, compressed air must pass through multiple obstacles before being discharged to the four-way valve. As the volume of the return tank suddenly increases exponentially, the air flow rate is significantly reduced, combined with obstacles such as blocking the oil, compressed air The oil molecules in the intensified collision, adhered to the inner wall and the net surface, and then flowed into the bottom, and the compressed air that was purified again flowed to the four-way valve.  

There is a direct-flow cock under the return tank, which can control the lubricating oil leaf that supplies the vacuum pump. There is no liquid level tube, and the oil storage and oil quality can be observed.  

8, boom  

The boom is located at the top of the container. It is composed of a suspension rod seat, connecting pipe counterweight, and a supporting frame. The suction hose is connected to the front and the siphon hanger rod can be operated afterwards. The boom can rotate more than 270 feet. Since the counterweight block is set to bear the labor intensity when the suction pipe is used, the connecting pipe bend angles at both ends of the support pipe are 90, and the bent outer diameter is provided with a clearing hole, which is usually sealed when sucking the hose or When the straw is clogged, the clear hole cover can be opened to clear the blockage.  

9, locking mechanism

The locking mechanism is mainly composed of a fixing device, and its function is to ensure the sealing of the cleaning hole cover. The fixing device is located at the lower right middle of the frame, and is mainly composed of an operating rod, a locking pin, a positioning plate, etc., and is connected with a pull rod, a thread fork-shaped joint, or the like. When the operating rod moves backwards, the rod moves forward, and the rotating shaft swings the counterclockwise arm so that the cleaning hole cover tightly closes the cleaning hole to achieve the purpose of sealing. The operating rod is provided with a locking pin, a spring, a pull rod and a handle. When the joystick is moved back and the lock lock slides along the outer ring of the positioning plate into the positioning groove, the spring at the rear end of the locking lever enters the positioning groove. Since the five sides of the locking pin are restrained, it cannot be ejected. The positioning groove can ensure that the lever does not Because of the bumpy vibrations in the ride, it is said to achieve a tight function.