Main Structure and Operating Principle for sinotruk water tank truck

“Lv Ye” water tank truck is a leading product of our company. We provide various water tank trucks with capacities ranging from 1.5 tons to 30 tons to meet the requirements of different users. These water tank trucks are characterized with professional design, attractive appearance, large tank capacity, and various functions such as washing roads, watering pavements, fire fighting upon emergency, forced washing, and gravity irrigation. They are generally used in specialized departments engaged with landscaping and sanitation in cities and towns as well as large- and medium-sized enterprises and public institutions involved in roads, governmental agencies, schools, factories, and mines.

A water tank truck (a large-tonnage sprinkling truck is used as an example in the description) is mainly made up of a class II automobile chassis, a tank body, a power take-off and drive system, a water circuit system,a gas circuit system, a rear operating platform (the front platform for small tonnage), and a side protective fence,as shown in the following Figure.
Main structure for our water tank truck
Figure 1

1.Class II chassis 2.Tank body 3.Power takeoff and drive system 4.Water circuit system 5. Side protective fence 6. Rear operating platform 7. Rear bumper 8.Overhead spray gun
1. Tank body assembly
The tank body is a metal-based atmospheric tank. It involves a carbon-steel tank and a stainless steel tank.A carbon-steel tank is treated against corrosion in its interior.A tank body has an oval section or a round-square section (a rectangle with circular arc). The head is processed automatically by a computerized numerical control (CNC) beading machine for attractive appearance and high rigidity. The shell is made of longitudinally butt jointed plates and welded through the automatic gas shielded welding method. After being jointed, the plates are rolled by a six-meter rolling machine to shape the tank as a whole with attractive appearance and excellent straightness. The shell and the head are
welded through the penetration butt welding method.A swash plate is installed inside the tank body, and a longitudinal swash plate is installed in some tank bodies to alleviate the impact of the liquid inside the tank body on the head and shell. A setting tank and a drain outlet are available at the bottom of the tank body. The drain outlet can be opened as appropriate to discharge the dirt in the setting tank.

2. Drive system

The drive system is made up of a power takeoff, a control system, and a drive shaft, etc.After being powered from the power takeoff, the engine transmits the power to the water pump through the drive shaft to run the water pump. The control system of the power takeoff can be operated in manual mechanical manipulation or electronically pneumatic manipulation mode.

Manual mechanical manipulation: Press the clutch pedal, and then pull the control handle of the power takeoff for the engagement between the gear of the power takeoff and the gear of the gearbox. Loosen the clutch pedal to transmit the power of the engine to the water pump through the drive shaft.

Electronically pneumatic manipulation: Transmit the power by changing the break-make mode of the gas circuit. There is a control switch for the power takeoff on the instrument panel of the cab. Press the clutch pedal,and then pull the control switch to connect the gas circuit. When the compressed air is transferred to the air cylinder of the power takeoff through the air reservoir and it pushes the piston inside the cylinder, the shifting fork of the power takeoff results in the engagement between the output shaft gear and the input shaft gear. The power is transmitted after the clutch pedal is loosened.

Drive shaft: The drive shaft of the water pump uses cross cardan joints at both ends, with a high-frequency welded pipe in the middle and the flexible spline at one end.

3. Water circuit system

(1) The water circuit system is made up of a water pump, a front water spray, an overhead spray gun,a rear watering device,a pressure drainage device, and a gravity drainage device, etc. Its operating principle is shown in the following figure.


(2) See the Operating Instruction for Water Pump for information about the structure and principle of the water pump.
The water pump are used and maintained as follows:
1) Using the water pump
● Before starting a water pump, check the oil level of the gearbox. If the oil level is low, add oil. Keep the oil level of the gearbox within the gap of the level rod to avoid insufficient or excessive oil.
● Before commissioning a water pump, add liquid into the water pump to avoid failed self-suction or damage to the mechanical seal.
● Check the rotating components of the pump for jam.
● Check the base angle and clamp nuts for looseness.
● Check the suction line for air leakage.
● Open the valve of the suction line, and slightly open the outlet valve.
● After starting the water pump, check whether the rotating direction is correct and whether abnormal noises and vibrations are generated.
● Upon completion of the self suction of the pump, the pointers of the pressure gauge and vacuum gauge are stabilized. At this point, adjust the outlet valve to limit the reading of the pressure gauge in the specified range, avoiding an overloaded engine caused by excessive starting power or cavitation of the pump caused by excessive flow.
● For self suction of the pump, after being started, the pump must run at a speed equal to or faster than the rated speed, because slow running for a long time will extend the self-suction time and even fail the self-suction task.
● A shifting slide gear of the QSYB pump must be shifted when the pump is not running to avoid damages to the gear.
2) Maintaining the water pump
● In a cold season, drain the liquid from an idle pump to avoid damage to components caused by the frozen liquid.
● Replace the worn rolling bearings with new ones.
● Do not open and check the mechanical seal when no leakages are found. If serious leakages are found in a leak hole, open and check the mechanical seal immediately. Gently remove and handle the mechanical seal to ensure a clean sealing surface and protect the mirrors of the rotating and stationary seal rings. Do not damage the mirrors. The leakage of the mechanical seal mainly results from the galling mirror. Inappropriate installation or aging of the rubber seal can also result in leakage. Therefore, the rubber seal must be repaired, adjusted or replaced upon inappropriate installation or aging.
4. Gas circuit system
Make use of the build-in air source of the automobile, manipulate the air cylinder by using the solenoid valve, and open or close the valve for different operations.
5. Operating platform
Two kinds of operating platforms are available. They are installed on the automobile frame behind the tank body or in front of the tank body according to the requirement.