QC/T 793-2020Air filter for motorcycles and mopeds (English PDF)

3.1 Air filter with dry paper element

An air filter, which uses dry filter paper as the filter element.

3.2 Air filter with paper element louvered by engine oil

An air filter, that uses filter paper with an appropriate amount of engine oil sprayed on the surface as the filter element.

3.3 Air filter with foam plastic filter element

An air filter, which uses a foam material soaked in an appropriate amount of engine oil as the filter element.

3.4 Rated air volume flow

The volume of air flowing through the air filter outlet per unit time under standard atmospheric conditions specified by the user or manufacturer. It is determined based on the actual demand measurement and calculation of the engine. See Appendix A for the recommended calculation formula.

3.5 Resistance

When air flows through the air filter, the static pressure value measured at the downstream pressure measuring point of the air filter under test.

3.6 Initial resistance

For a new air filter, the static pressure value as measured at the downstream pressure measuring point at rated air volume flow.

3.7 Filtration efficiency

The ability of the test piece to filter out specific test dust according to the prescribed test method, which is expressed as the mass percentage (%) of the dust filtered by the test piece to the mass of the added dust.

3.8 Initial filtration efficiency

The ability of an air filter equipped with a new filter element to filter out specific test dust according to the prescribed test method, which is expressed as the mass percentage (%) of the filtered dust to the mass of the added dust.

3.9 Full life filtration efficiency

The filtration efficiency measured when the test termination condition is reached, which is evaluated by the mass percentage (%) of dust filtered by the test piece during the entire test to the dust added.

3.10 Dust holding capacity

The total amount of specific test dust filtered out by the test piece, when the test termination condition is reached.

3.11 Inner cleanliness

The mass of impurities remaining in the air filter cavity before use.

3.12 Recovery ratio of air flow resistance

The ratio -- of the initial resistance of the assembly with a new filter element TO the resistance after the dust holding capacity test (laboratory life test) is completed, that is, after the filter element is cleaned, expressed as a percentage (%).

3.13 Shower load

The amount of water added per unit of effective filtration area of the filter element.

5.2.10 Air filter/filter element's water immersion resistance

After the air filter with paper filter element is soaked in (23 ± 5) °C pure water for 4 hours, the paper pleats of the filter element shall not be damaged.

5.2.11 Recovery ratio of air flow resistance

After the air filter/filter element's dust capacity test is completed, the recovery ratio of air flow resistance shall not be less than 80% after performing restorative treatment on the air filter element.

5.2.12 High and low temperature resistance

After the air filter is subject to the high and low temperature resistance test, no structural defects such as brittleness and deformation are allowed; the sealing performance of the assembly shall meet the requirements of 5.2.6.

5.2.13 Water splash resistance of air filter/filter element

After the air filter is subject to the shower test at a shower load of 50 g/m2 per unit effective filtration area, its filtration efficiency shall meet the requirements of 5.2.2; the dust holding capacity shall not be less than 90% of the value specified in 5.2.4.

6.1 Initial resistance test

The initial resistance test is performed in accordance with 6.3 in GB/T 28949-2012.

6.2 Initial filtration efficiency test

6.2.1 In the initial filtration efficiency test, the dust concentration is 1 g/m3, the dust mass is 20 g.

6.2.2 The initial filtration efficiency test is performed in accordance with 5.1.4 in QC/T 32-2017.

6.3 Test of full life filtration efficiency and dust holding capacity

6.3.1 The dust concentration for the full life filtration efficiency and dust holding capacity test is 1 g/m3. The test termination condition is that the air filter resistance reaches the specified value of 3 kPa.

6.3.2 The test methods for full life filtration efficiency and dust holding capacity are carried out in accordance with 5.1.6 in QC/T 32-2017.

6.4 Inner cleanliness test

The test method for inner cleanliness of wet air filters shall be implemented in accordance with QC/T 683. The test method for inner cleanliness of dry air filters is carried out according to 5.1.1 in QC/T 32-2017.

6.5 Sealing test

After the air filter's filtration efficiency test or dust holding capacity test, immediately disassemble the air filter, to check and record whether there is any dust leakage in the sealing parts inside the air filter.

6.6 Vibration resistance test

6.6.1 Fix the air filter on the special fixture of the vibration test bench, according to the installation method when loading; then send the vibration bench to the temperature control box.

6.6.2 According to the conditions of vibration frequency of 50 Hz, vibration acceleration of 98 m/s2, temperature of (-20 ± 1) °C, vibrate in the up and down direction for 1 hour. Then heat up to (80 ± 1) °C. Vibrate in the up and down direction for 1 hour. After the vibration is completed and the temperature returns to normal, remove the vibration bench from the high and low temperature box. Conduct a comprehensive inspection of the outside of the air filter, to see if there are any cracks, deformations and other structural defects in each component. If there is any defect, stop and follow each test step according to 6.6.3.

6.6.3 Then, according to the conditions of vibration frequency of 50 Hz, vibration acceleration of 98 m/s2, temperature of (23 ± 5) °C, vibrate in the front, rear, left and right directions for 1 hour each. After the vibration is completed, check whether it complies with the provisions of 5.2.1 and 5.2.8. Disassemble the air filter and comprehensively inspect each component for cracks, deformation, or other structural defects.

6.7 Air leakage test

6.7.1 While ensuring that the test pipeline is sealed, securely connect the new air filter to be tested to the test device as shown in Figure B.1. The air filter inlet and all possible air inlet locations on the non-clean air side shall be tightly sealed.

6.7.2 Start the vacuum pump, to vacuum at the air outlet. Adjust and stably maintain the vacuum value on the clean side of the air filter at 5 kPa.

6.7.3 Measure the air leakage on the clean air side at the sealing edges of the filter element and the upper and lower end covers. Record the measurement results.

6.12 Water splash resistance performance test of air filter/filter element

6.12.1 Securely connect the new air filter to be tested to the test device as shown in Figure B.2.

6.12.2 Under the rated air volume flow, start the water spraying system. According to the effective filtration area of the filter element, determine the water spraying amount, at a watering load of 50 g/m2. Continuously spray, at a shower concentration of 5 g/m3 and dry compressed air at a pressure of 100 kPa. Stop the test after the water reaches the specified value.

6.12.3 After shower, the test piece shall be continuously ventilated and dried at the rated air volume flow, until the pressure drop returns to the initial value or becomes stable.

6.12.4 The dried test piece shall be subjected to performance testing according to the requirements of 6.2 and 6.3. The filter element status and measurement results shall be recorded.

7.1 Categories of inspection

The inspection of air filters is divided into two categories: exit-factory inspection and type inspection.

7.2 Exit-factory inspection

The exit-factory inspection items are listed in 5.1.

7.3 Type inspection

7.3.1 Products shall undergo type inspection when one of the following circumstances occurs.

a) Type finalization inspection of trial production of new products or old products after trans-plant production (the first batch of products manufactured after identification and type finalization);

b) After formal production, there are changes in structure, materials, processes, suppliers, etc.;

c) During formal production, periodic inspections shall be carried out regularly or after accumulating a certain amount of output;

d) When the production is resumed after suspension for more than half a year.

7.3.2 The samples for type inspection shall be selected from the same batch of products that have passed the exit-factory inspection; the inspection items shall be all items specified in Chapter 5.

8.1 Marking

8.1.1 Each set of products shall be marked with the permanent mark of the manufacturer (factory name or factory logo); the location of the mark shall not affect product performance and appearance.

8.1.2 The outer surface of the packaging box shall be marked of the following.

a) Manufacturer's name, factory logo or trademark;

b) Product name;

c) Product model;

d) Quantity and total mass;

e) Packing box volume dimensions (length × width × height);

f) Storage and transportation pictorial signs such as "Handle with caution" and "Avoid moisture" shall comply with the provisions of GB 191;

g) Manufacturing date;

h) The number of the implemented standard.

8.2 Packaging, transportation, storage

8.2.1 Each air filter shall be accompanied by a product certificate and product use and maintenance instructions.

8.2.2 The air filter shall be put into a packaging bag, which is made of waterproof material; then put into a dry packaging box.

8.2.3 The exit-factory packaging of the air filter shall ensure that it is not damaged during normal transportation.

8.2.4 The air filter shall be stored in a dry and ventilated warehouse. Under normal