QC/T 1061-2017Road tank vehicles for light fuel oil - Overfill prevention systems (English PDF)

3.1 Overfill prevention system

A system consisting of an anti-overflow sensor and an anti-overflow socket connected by a cable.

3.2 Overfill prevention optic sensor

A sensor installed at the top of the tank to determine whether the liquid level in the tank exceeds a specified height.

3.3 Overfill prevention socket

Interface for anti-overflow system and external connection.

4.1 Basic requirements

4.1.1 Each component of the anti-overflow system shall meet the requirements of this standard and shall be manufactured according to the product drawings and technical documents.

4.1.2 The raw materials, purchased parts, and outsourced parts applied to each component of the anti-overflow system shall meet the requirements of relevant standards.

4.2 Materials

4.2.1 The selection of housing material and sealing material must fully consider its compatibility with the medium in contact.

4.2.2 The housing of the sensor and socket in the anti-overflow system should be made of aluminum alloy or stainless steel, and should not be made of cast iron and non-metallic materials.

4.3 Conductive resistance

The value of the static resistance between the conductive parts and the housing of the anti-overflow system components that conduct static electricity shall not be less than 10^6 ohm.

4.4 Design temperature

The design temperature of the anti-overflow sensor should be -20 °C. When there are special environmental requirements, the design temperature should be -40 °C ~ 70 °C.

4.5 Explosion-proof performance

4.5.1 The anti-overflow sensor shall be intrinsically safe and shall comply with the requirements of GB 3836.1 and GB 3836.4.

4.5.2 The explosion-proof performance shall meet the requirements of the explosion-proof mark Ex ia II B T4. The specific description is as follows.

a) Ex mark;

b) ia Intrinsically safe electrical equipment. Sparks or thermal effects generated during normal operation or under standard test conditions must not ignite explosive mixtures;

c) II Electrical equipment. Explosive environments other than coal mines;

d) B gas group. the maximum test safety clearance is 0.5 mm ~ 0.9 mm, and the minimum ignition current ratio is 0.45 ~ 0.8;

e) T4 temperature level. The maximum surface temperature of electrical equipment is 135 °C.

4.5.3 The protection level of the metal case of the anti-overflow sensor is not less than the IP 54 protection level specified in GB 4208.

4.6 Level sensing

4.6.1 When the liquid level reaches the sensing position of the anti-overflow sensor, the anti-overflow sensor shall issue a liquid level alarm.

4.6.2 When the anti-overflow sensor is in a dry state, the anti-overflow system is in a normal working state, and the liquid level replacement phenomenon must not occur.

4.7 Sealing

The test pressure is 36kPa, the holding time is at least 60s, and there must not be visible leakage at the connection between the anti-overflow sensor body and the housing.

4.8 Service life

4.8.1 When the anti-overflow sensor is in the dry state, after a continuous power-on and on-hook time of 48h, no short circuit or open circuit shall occur.

4.8.2 The anti-overflow sensor shall not be short-circuited or open-circuited after 25 000 uninterrupted tests in both wet and dry states.

4.9 External connection dimensions

The dimensions of the anti-overflow socket interface shall meet the requirements of Appendix A.

4.10 Electrical wiring

The cross-sectional area of the copper core wire of a single wire should not be less than 0.75 mm².

4.11 Contact arrangement

See Table 1 for the contact arrangement between the sensor and the six-core socket in the anti-overflow system.

5.6 Anti-overflow sensor service life test

5.6.1 When the anti-overflow sensor is in the dry state, continuous power is applied, and the on-hook time is not shorter than 48 hours.

5.6.2 Place the anti-overflow sensor in the container and continuously switch between wet and dry states, and perform 25 000 continuous measurements.

After the test, there should be no damage such as short circuit or open circuit, which will make the liquid level undetectable.

5.7 Conduction resistance test

5.7.1 The anti-overflow system and its components should be dried before the test.

5.7.2 Use 500 V DC megohmmeter to measure resistance.

5.7.3 Measure the electrostatic resistance between any conductive part on the anti-overflow component that may be in contact with the medium and the case.

6.1 Factory inspection

6.1.1 Each product shall be inspected from the factory according to the specified items, and only after passing the inspection by the manufacturer and issuing a product certificate leave the factory.

6.1.2 Factory inspection items

a) appearance;

b) level sensing test;

c) Conductive resistance.

6.2 Type test

6.2.1 Type inspection shall be carried out in any of the following cases.

a) When new products are trial-typed;

b) When it is in production, if it is produced continuously for 3 years or when the cumulative output is 10,000 units;

c) After the formal production, if the structure, material and process are changed greatly, which may affect the performance of the product;

d) When there is a significant difference between the factory inspection and the type inspection.

6.2.2 In the case of type inspection, if it is a) or b) in 6.2.1, it shall be inspected according to Chapter 4; if it is c) or d) of 6.2.1, only the affected items can be inspected.

7.1 Product identification

The product logo should be cast or engraved on the product body, or it should be permanently fixed on the product with a type of identification plate and clearly visible.

7.2 Anti-overflow sensor identification

The identification of the anti-overflow sensor should include at least the following.

a) manufacturer name or trademark;

b) manufacturer's model;

c) Explosion-proof mark;

d) explosion-proof certificate number;

e) production date or batch number;

f) Other working conditions that require special instructions.

7.3 Anti-overflow socket identification

The identification of the anti-overflow socket shall include at least the following.

a) manufacturer name or trademark;

b) manufacturer's model;

c) production date or batch number.