Introduction of fuel tankers（Part 1） - use and maintenance

Introduction of fuel tankers（Part 1）

- use and maintenance

1. Overview

Light fuel transport vehicles can be divided into tanker trucks and refueling vehicles. It is mainly used for filling and transportation of light fuels such as gasoline, kerosene, diesel, and other non corrosive liquids when necessary, as shown in Figure 1 below.

2. Quality standards

All fuel tankers must meet the standard of GB18564.1-2019 “Tank Vehicles for Road Transportation of Dangerous Goods”.

3. Main structure

The main structure of the light fuel oil transport vehicle includes: Class II vehicle chassis, tank assembly, safety accessories, pipeline system, oil delivery hose, grounding rubber tape and static conductive plate, electrical system, protective device, etc., as shown in Figure 2 below.

(Figure 2. Composition of fuel tanker)

1. Chassis 2. Tank assembly 3. Manhole cover assembly 4. Rear ladder assembly 5. Pipe box assembly 6. Rear bumper assembly 7. Rear combination lamps 8. Rear oil discharge pipe assembly 9. Electrostatic conductive assembly 10. Fender assembly 11. Tension frame assembly 12. Sedimentation frame assembly 13. Side guardrail assembly 14. Power system 15. Control box assembly 16. Overflow pipes 17. Exhaust pipes

1) Tank assembly

The main structure of the tank assembly is shown in Figure 3 below.

1. Dish head 2. Tank foot 3, Wave preventer 4, Oil drain 5, Subsea valve 6, Safety frame

7. Manhole 8. Tank body 9. Overflow pipe

(Figure 3. Tank structure)

The cross-sectional shape of the tank body is divided into oval and “round rectangle”. Several wave proof plates are welded in the tank to reduce the impact of fuel in the tank. The tank bottom is equipped with a sedimentation basin and a sewage outlet, which can be opened irregularly according to the situation to discharge the water and dirt accumulated at the bottom of the tank.

The upper part of the tank is equipped with a safety frame, which can store the oil spilled when filling the tank for easy cleaning, or let it flow out through the overflow pipe at the front end of the tank, so as not to pollute the external surface of the tank. The oil drain port at the bottom of the tank can be connected with the oil drain pipe to form an oil transport vehicle, or it can be connected with the oil pump inlet pipe to form a refueling vehicle. For heavy oil tanks, steam heating devices can be set as required to facilitate the discharge of oil at different temperatures.

The tank body is welded with high-quality carbon structural steel. Users can choose stainless steel or other non-ferrous metal tanks according to their needs.

The tank body is fixed on the beam of the vehicle chassis frame with U-bolts and connecting plates through the tensioning frame on the tank leg. A rubber plate is added between the tank leg and the frame (There is not this part if there is no requirement for refitting the chassis), which plays the role of shock absorption and noise reduction.

2) Manhole cover assembly

In order to facilitate the maintenance personnel to enter the tank for maintenance, the upper part of the tank is equipped with an upper cover assembly. Loosen the bolts of the snap ring of the upper cover, remove the snap ring, and remove the upper cover, so as to check the oil in the tank and fill the tank with oil.

Check the working condition of the breather valve to ensure that it works sensitively and reliably.

The upper cover assembly adopts an intelligent manhole cover, which is composed of a built-in breathing valve and an emergency exhaust device. In the process of use, it can automatically adjust the pressure in the oil tank to balance the internal and external pressure. When the tank is dumped, the breather valve will be automatically closed to effectively prevent oil leakage. When the external temperature of the tank is too high and the pressure in the tank increases by more than 21~30kpa, the emergency exhaust device will be opened to release the pressure in the tank, and the maximum exhaust volume will reach 7000m/h, which can effectively prevent explosion.

3) Power control system and subsea valve control system (generally, oil transport vehicles do not have this system)

① The power of the engine transmission box is taken out by the power takeoff and transmitted to the speed increase box before the oil pump through the transmission shaft, so as to drive the oil pump to work and realize the setting function. The power takeoff lever is usually pneumatically operated, that is, a switch in the cab is used to control the on-off of the compressed air circuit, so as to realize the output of power.

② The subsea valve, also known as the emergency shut-off valve, is installed at the bottom of the tank, which can change the traditional top refueling to carry out the bottom refueling, making the operation simpler, safe and environmentally friendly. A cut-off groove is designed on the valve body. In case of an accident of the oil tank vehicle, the cut-off groove will be disconnected, and the pipeline under the vehicle will be cut off from the tank without affecting the sealing of the tank, so as to effectively prevent the oil leakage from the tank, so as to ensure the safety of the tank.

③ The subsea valve is controlled by the manual reversing switch in the cab. When there is no compressed air or it cannot be opened normally for special reasons, it can also be opened manually without Dismantling the valve.

4) Oil pump and power system

The power transmission system of oil pump is composed of power take-off, transmission shaft and oil pump. The power take-off is installed on the main transmission of the chassis, and the engagement and disconnection of the power take-off gear and the transmission gear are realized through the joystick next to the seat in the cab. When the power take-off needs to work, step on the clutch pedal, shift the gear lever to neutral, press the power take-off control handle, make the power take-off gear mesh with the transmission gear, release the clutch, and the oil pump starts to work. To stop the oil pump, put down the power take-off handle, and the oil pump stops working (Note: when the car is driving, it is strictly forbidden to operate the power take-off handle, otherwise, it is easy to cause damage to the power take-off gear and transmission gear).

5) Pipeline system

① The pipeline system of the oil transportation vehicle is relatively simple, that is, a straightway valve is installed on the drain pipe to control the discharge of oil. When the straightway valve is first used, it needs a large force to open it. After several times of use, it can be opened and closed with a small force. The opening force of the valve can be adjusted by adjusting the bolts on the end face of the valve. The valve has been adjusted when it produced in the factory. Users generally do not adjust it to avoid valve leakage.

② The pipeline system of refueling vehicle is relatively complex, which is generally divided into two structures.

The pipeline system structure of refueling vehicle (Type 1) is shown in Figure 4 below.

1. Tank, 2, 9 Three-way ball valve 3. Primary filter 4. Vacuum gauge 5. Oil pump 6. Flow gauge 7. Fine filter 8. Pressure gauge

(Figure 4. Pipeline system of refueling vehicle Type 1 )

The pipeline system structure of refueling vehicle (Type 2) is shown in Figure 5 below.

1. Tank, 2, 9 & 10. Three-way ball valve 3. Primary filter 4. Vacuum gauge 5. Oil pump 6. Flow gauge 7. Fine filter 8. Pressure gauge ,  A, B & C - Oil outlet Coupling fittings

(Figure 5. Pipeline system of refueling vehicle Type 2 )

Both structures are equipped with three-way ball valve, vacuum gauge, pressure gauge, primary filter, secondary filter, flow meter, etc. The second structure adds a three-way ball valve to the first structure. The relevant parts and components are described as follows:

a. The structure of the three-way ball valve is similar to that of the straightway ball valve, except that the opening pressure is adjusted through the cock at the bottom of the valve body. There is a concave color dot on the top of the valve rod of the three-way ball valve. When the color dot turns to the outlet, the ball valve closes this nozzle and connects the other two outlets at the same time.

The ball valve has been adjusted in the factory. Users generally do not adjust it to avoid valve leakage.

b. The primary filter assembly is installed in the front of the oil pump inlet and is the protective device of the oil pump. As shown in Figure 6 below. It can effectively prevent sundries from entering the oil pump. For the first three times when the new tank is put into use, after each use, disassemble the flange 1, hold the handle of the primary filter core 3, take out the filter element and clean it. In the later use process, the damaged filter element should be cleaned or replaced at any time according to the cleanliness of the oil quality. Do not take out the filter element during use, otherwise it will aggravate the wear of the oil pump or damage the parts in the oil pump.

(Figure 6. Primary filter)

1. Flange   2. Primary filter  3. Primary filter core

c. The fine filter assembly is the protective device of the flow gauge, as shown in Figure 6 below. It is able to filter out the impurities and dirt in the oil to prevent them from entering the flow gauge and damaging its components. At the same time, the fine filter assembly is also the last stage of filtration at the oil outlet, which can effectively ensure the cleanness of the separated oil. Its use requirements are the same as that of the primary filter assembly.

(Figure 7 Fine filter)

1. Flange   2. Fine filter  3. Fine filter core

d. The flow gauge is a measuring device for the refueling vehicle when it is working. It is a relatively precise measuring instrument. It has been adjusted in the factory. Generally, users should not adjust and disassemble it at will, as shown in Figure 7 below.

(Figure 8. Flow meter)

e. There are three joints in the refueling vehicle pipeline system, which can quickly realize the connection with the refueling pipes. At the same time, the joints are well sealed without leakage, as shown in Figure 9 below.

(Figure 9. Oil pipe joints)

6) Oil delivery hose

No matter the oil transport vehicles and refueling vehicles, put an oil delivery hose in the pipe boxes on both sides of the tank for the use of filling and discharging oil. As shown in Figure 10 below.

(Figure 10. Oil delivery pipeline)

7) Grounding rubber tape &  electrostatic conducting plate

In order to ensure the safety of the tank vehicle and prevent the fire caused by static electricity, a grounding rubber tape is set at the rear of the tank vehicle, as shown in Figure 11 below. One end of the grounding rubber tape is connected to the tank and the other end is grounded. It is absolutely not allowed to let the grounding rubber tape leave the ground during the use of the vehicle. After using for a period of time, if the grounding rubber tape is worn and became short, loosen the bolts of the fixed pressing plate at the rear of the frame, and pull out the grounding rubber tape for a suitable length. When it cannot be stretched any longer, it should be replaced with a new grounding rubber tape in time.

(Figure 11. Grounding rubber tape)

8) Protective device

According to GB11567-2019 “Requirements for Side and Rear Lower Protective Devices of Automobiles and Trailers”, safety barriers are set on both sides of the oil tank vehicle, which are fixed with lifting rails respectively. When necessary, the upper end of the diagonal brace can be fastened, the bolts can be removed, and the protective fence can be removed. The rear part is equipped with a rear bumper and fenders above the wheels.

9) Fire silencer

For safety and fire prevention, most oil tank vehicles are equipped with fire caps, which can directly enter the oil depot or gas station during use. You can also choose a fire silencer instead of a fire cap.

10) Marker light

The fuel tanker is a special vehicle for transporting inflammables and explosives. A red marker light (optional according to user requirements) should be set above the cab.

11) Vehicle identification code

The vehicle identification code is engraved on the product label of the tank vehicle.

By  WONDEE Autoparts

2022-7-29