QC/T 1110-2019Fuel heating devices for automotive diesel engines (English PDF)

3.1 Diesel fuel heating function

Under specified conditions, the efficiency of heating diesel oil to a set temperature.

3.2 Diesel fuel heating unit

Components, which have diesel heating function and are capable of heating diesel as required, including but not limited to fuel tank heating unit, fuel filter heating unit, fuel pipe heating unit.

3.3 Automotive diesel fuel heating system

A device, which is composed of a diesel heating unit and a temperature controller, uses on-board energy to heat the fuel, to ensure that the fuel supply system of the diesel engine normally supplies diesel (hereinafter referred to as the heating device).

4.1 General requirements

4.1.1 The heating device shall meet the requirements of this standard AND be manufactured according to the product drawings and technical documents, which are approved by the prescribed procedures.

4.1.2 The working environment conditions of the heating device shall comply with the provisions in 3.1.2 of QC/T 413-2002.

4.1.3 The rated operating voltage of the heating device shall be 12 V (DC) or 24 V (DC).

4.1.4 The heating device shall comply with the provisions in 8.6.9 of GB 7258-2017.

4.2.5 Requirements for temperature resistance

For heating devices installed on the engine, the minimum operating temperature shall not be higher than -41 °C; the maximum operating temperature shall not be lower than 120 °C. For heating devices installed in other locations, the minimum operating temperature shall not be higher than -41 °C; the maximum working temperature shall comply with the requirements in 3.1.3 of QC/T 413-2002.

4.2.6 Vibration resistance

The heating device installed on the engine shall be able to pass the vibration test, which is specified in 5.9.2 of QC/T 772-2017. The heating device installed in other positions shall be able to pass the vibration test, which is specified in GB/T 18296. The heating device after the test shall comply with the provisions in 3.2 of QC/T 413-2002.

4.2.7 Requirements for salt spray resistance

It shall meet the requirements in 3.13 of QC/T 413-2002.

4.2.8 Reliability requirements

Under the conditions specified in 8.1 of GB/T 18297-2001, the continuous normal working time of the heating device shall not be less than 1000 h.

4.2.9 Safety requirements

4.2.9.1 The heating device shall comply with the provisions on flame retardancy in 8.6.2 of GB 7258-2017.

4.2.9.2 When heating is controlled manually, the temperature of the heated diesel oil is not allowed to exceed 45 °C; when the temperature of the diesel oil exceeds 45 °C, it shall be turned off (stop heating). When heating is automatically controlled, the temperature of the heated diesel oil shall not exceed 38 °C (set as required, not allowed to exceed 45 °C).

4.2.10 Overvoltage resistance of power supply

It shall meet the provisions of 4.3 in GB/T 28046.2.

4.2.11 Resistance to reverse polarity of power supply

It shall meet the requirements of 3.7.1 in QC/T 413-2002.

4.3 Installation requirements

4.3.1 Heating device

When installing the heating device, the connection shall be firm and reliable; it shall be easy to disassemble, maintain, and service. There shall be no interference with other parts. The tightening torque of threaded fasteners shall comply with the provisions of QC/T 518. The heating device shall have no adverse effect on the fuel supply to the engine.

4.3.2 Fuel tank

The fuel tank, which is equipped with diesel heating unit, shall comply with the provisions of GB 18296.

4.3.3 Fuel pipe

There shall be no leakage in the fuel pipe on which the diesel heating unit is installed.

4.3.4 Fuel filter

The fuel filter, which is equipped with the diesel heating unit, shall comply with the provisions of GB/T 28953.

4.3.5 Engine

Engines and their accessories, which are equipped with heating devices, shall comply with the provisions of Chapter 5 of GB 7258-2017.

5.1 Test conditions and appearance inspection

5.1.1 Test conditions

The diesel oil used for the test shall be No.0 light diesel oil; the temperature measurement accuracy shall be 1%; the power supply voltage used for the test shall be 12/24 V (DC).

5.1.2 Appearance inspection

The appearance and sign of the product are inspected visually; the external dimensions of the product are inspected by general or special measuring tools.

5.2 Heating capacity test

5.2.1 In the ambient temperature test chamber, when the ambient temperature and the fuel oil temperature of the diesel engine are both at -10 °C, after the heating device starts to heat for 20 minutes, it shall be possible to ensure that the diesel engine, that meets the requirements of QC/T 471, is started normally on the test bench; its idling continuous running time is not less than 20 min. Other test requirements shall be implemented, in accordance with the relevant provisions of QC/T 471.

5.5 Electromagnetic compatibility test

It shall be carried out according to the provisions of 4.9.1.1 and 4.9.2 in QC/T 413-2002.

5.6 Resistance to temperature and humidity performance test

It shall be carried out according to the provisions of 4.10 and 4.11 in QC/T 413-2002.

5.7 Vibration resistance test

For the heating device installed on the engine, the vibration resistance test shall be carried out, according to the provisions in 5.9.2 of QC/T 772-2017; for the heating devices installed in other positions, the vibration resistance test shall be carried out, according to the provisions in GB 18296.

5.8 Salt spray resistance test

It shall be carried out according to the provisions of GB/T 2423.17.

5.9 Reliability test

The heating device shall be installed on the test equipment; it shall work continuously for 1000 h, under the low-temperature start-up test conditions, which are specified in GB/T 18297-2001.

5.10 Safety (flame-retardancy) test

It shall be carried out according to the provisions of GB 8410.

5.11 Power supply overvoltage resistance test

It shall be carried out according to the provisions of 4.3 in GB/T 28046.2-2001.

5.12 Performance test of resistance to reverse polarity of power supply

It shall be carried out according to the provisions of 4.7.1 in QC/T 413-2002.

5.13 Installation test

For the fuel tank equipped with the heating device, the vibration resistance test shall be carried out, according to the provisions of GB 18296; for the fuel filter and the fuel pipe equipped with the heating device, the vibration resistance test shall be carried out according to the provisions of 5.7.

6.1 Inspection types

Product inspection is divided into exit-factory inspection and type inspection.

6.2 Exit-factory inspection

Products can only leave the factory after passing the inspection; meanwhile it shall be accompanied by corresponding product quality certificates or marks. The inspection items of the exit-factory inspection are as shown in Table 1.

6.3 Type inspection

6.3.1 Several situations in which type inspection shall be carried out.

In case of any of the following conditions, the manufacturer shall carry out type inspection:

- Product finalization identification of new products or old products after trans-plant production;

- After formal production, where there are major changes in structure, materials, processes, that may affect product performance;

- Not less than once every 3 years for products, which are produced in batches or large quantities;

- When the production is resumed after being discontinued for more than one year;

- When the exit-factory inspection results are significantly different from the previous type inspection results;

- When the national supervisory agency requests type inspection.

6.3.2 Number of samples

Products for type inspection shall be selected from the same batch (not less than 100 sets) of products that have passed the exit-factory inspection; the samples taken shall not be less than 12 sets.

6.3.3 Inspection items

For the inspection items of type inspection, see Table 1.

6.3.4 Qualification

The type inspection of the product shall comply with all the inspection items specified.

When one inspection item is unqualified, it shall re-take double number of products, for re-inspection on the unqualified item. If there is still unqualified, the batch of products is judged as unqualified. However, when the heating test, heating control test or heating protection function test fails, it shall not be re-taken for reinspection.